Topic 24 of 99: Beyond Planet Earth
Wed, Nov 17, 1999 (15:23) |
Marcia (MarciaH)
Geology in the Solar System other than Planet Earth
1087 responses total.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 1 of 1087: Marcia (MarciaH) * Wed, Nov 17, 1999 (15:34) * 27 lines
A Hawaiian-Style Volcano on Io
New images from Galileo reveal unexpected details of
the Prometheus volcano on Io including a caldera and
lava flowing through fields of sulfur dioxide snow.
November 5, 1999: A volcanic crater
several times larger than one found at
Hawaii's Kilauea volcano has been
photographed on Jupiter's moon Io
during a close flyby performed by
NASA's Galileo spacecraft.
"It appears that the Prometheus
volcano on Io has characteristics
remarkably similar to those of the
Kilauea volcano in Hawaii, although
Prometheus is much larger," said Dr.
Laszlo Keszthelyi (KEST-ay), a
Galileo research associate at the
University of Arizona, Tucson, AZ.
"Both volcanoes are long- lived
eruptions, with flows that apparently travel through lava tubes and produce plumes
when they interact with cooler materials."
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 2 of 1087: Marcia (MarciaH) * Wed, Nov 17, 1999 (16:41) * 8 lines
For the above photo, the caption:
Right: This is a high-resolution image of part of Prometheus, an active volcano on Jupiter's volcanic
moon Io. In earlier, lower resolution images, it appeared that all the dark material at Prometheus
comprised a single, long lava flow. The new image shows for the first time that the northeastern end of
this dark feature is actually a lava-filled caldera 28 kilometers (17 miles) long and 14 kilometers (9
mile s) wide. The underground source of the Prometheus lava is probably beneath this newly
discovered caldera. Galileo scientists are intrigued also by the snowfield containing hummocks, seen
to the east of the Prometheus caldera.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 3 of 1087: Marcia (MarciaH) * Wed, Nov 17, 1999 (16:54) * 38 lines
LEONID METEOR SHOWER
Leonids in the
Crystal Ball -- On the
morning of November 18,
1999, bits and pieces of
periodic comet
Tempel-Tuttle will hurtle
into Earth's atmosphere
at a head-spinning
158,000 mph. There is
little danger - few of the
meteoroids will reach the ground. Most will disintegrate
and in the process produce a streak of light in the sky
called a meteor. The meteors caused by debris from
comet Tempel-Tuttle are known as Leonids because
they appear to come from the direction of the
constellation Leo.
Most years the November Leonids aren't much to write
home about. Observers see no more than 10 to 15
meteors per hour. But every 33 years something
special happens. Comet Tempel-Tuttle swings through
the inner solar system bringing with it an especially
dense cloud of debris. The last time this happened was
in January 1998, and the November 1998 Leonids
were spectacular.
Experts think that this year's Leonids be even better,
with peak rates greater than 1000 shooting stars every
hour. The place to be on November 18, 1999 is
certainly outside and looking up! For the next two
weeks, Thursday's Classroom will present lesson plans
about meteor showers and the Leonids. We'll also be
inviting kids to participate in real NASA research by
counting meteors.
http://www.thursdaysclassroom.com/index_28oct99.html
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 4 of 1087: Gi (patas) * Wed, Nov 17, 1999 (17:15) * 1 lines
The last time a "star shower" was predicted everybody in and around Lisbon went out of town to watch the skies. They were in for a big time disappointment. That was more than three years ago but I'm not sure when (I still lived in my old apartment and stayed up late to watch from my window). So now the papers are being very cautious about the Leonids. They say it "might" be worthwhile to watch for them ;-)
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 5 of 1087: Marcia (MarciaH) * Wed, Nov 17, 1999 (17:44) * 4 lines
Meteors and comets are such difficult things to predict. No one knows what has happened since the last swing around the sun, and sometimes, they just disappear into the sun and are never seen again.
Maggie just sent this URL for Live Cam broadcast of the Leonids
http://www.live-leonids.org/en/live.html
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 6 of 1087: Marcia (MarciaH) * Wed, Nov 17, 1999 (17:45) * 0 lines
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 7 of 1087: Marcia (MarciaH) * Wed, Nov 17, 1999 (17:51) * 1 lines
The Broadcast begins in 10 minutes - at 5 pm Austin time.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 8 of 1087: Wolf (wolf) * Wed, Nov 17, 1999 (20:15) * 1 lines
we're supposed to see some of a meteor shower tonight at 8 central time. i had just about forgotten!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 9 of 1087: Marcia (MarciaH) * Wed, Nov 17, 1999 (20:30) * 1 lines
Now you know! Put a sticky-note on the bridge of your nose so you do not forget *grin*
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 10 of 1087: MarkG (MarkG) * Thu, Nov 18, 1999 (06:01) * 10 lines
As I interpret the information:
The Tempel-Tuttle comet comes by every November.
Every 33 years it comes close enough to break into our atmosphere.
It permanently fires off meteoroids everywhere it goes all the time.
Is that right?
Would it be orbiting around the sun?
I am such a dunce astronomically - someone hold my hand.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 11 of 1087: Marcia (MarciaH) * Thu, Nov 18, 1999 (14:10) * 2 lines
This is correct. Anything orbiting in the solar system ultimately orbits the sun. It is a periodic comet which means it has returned at predictable times since its initial discovery. Haley's Comet is the most famous of these return visitors with a period of 75 years. On occasion Comets slam into the sun as their orbits decay and the sun's gravity draws them into itself. All that is left of the Temple-Tuttle Comet is meteor showers which follow the former comet's orbital path. Eventually, they too wi
l fall victim to gravity and be no more.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 12 of 1087: Marcia (MarciaH) * Thu, Nov 18, 1999 (14:11) * 1 lines
(Since you are not using your hand for Cricket at this time of the year, I would be delighted to hold it, astronomically and virtually!)
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 13 of 1087: Maggie (sociolingo) * Thu, Nov 18, 1999 (17:51) * 1 lines
Wasted getting up at 2 a.m. skies cloudy couldn't see anything. Am I right in that the leonids are an annual event associated with the temple-tuttle comet? Is it possible there will be further showers tonight? We do have a clear sky now - typical!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 14 of 1087: Marcia (MarciaH) * Thu, Nov 18, 1999 (18:04) * 2 lines
Yes, there will be more tonight...but supposedly last night was the best viewing. I had the same result as you did in the middle of the night. Clouds!
(Hot and sunny here, as well!) I plan to look tonight again...hope springs eternal and all that...!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 15 of 1087: Marcia (MarciaH) * Thu, Nov 18, 1999 (18:07) * 1 lines
On Response 11 to MarkG I noted that it was debris from the Temple-Tuttle comet.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 16 of 1087: Marcia (MarciaH) * Fri, Nov 19, 1999 (00:02) * 2 lines
Please check Geo 15.26 and 15.27...the volcanoes on Io are shown in photographs and the caption which goes with them are there.
http://www.spring.net/yapp-bin/restricted/read/Geo/15.26
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 17 of 1087: Wolf (wolf) * Sun, Nov 21, 1999 (21:35) * 1 lines
i sat out for 20 minutes and saw one flare through the sky. i was lucky to see that one because there weren't anymore visible from my backyard.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 18 of 1087: Marcia (MarciaH) * Sun, Nov 21, 1999 (21:46) * 1 lines
Somewhere they counted 5,000 per hour. Bummer! I saw none, of course. All that blessing and dust control which makes our orchids so lovely obscures my skies most nights. Good for you to see that one! Did your kiddies see it, as well?
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 19 of 1087: Marcia (MarciaH) * Thu, Dec 2, 1999 (14:28) * 16 lines
Friday, December 3 NASA and its various websites listed below will carry live from Mars the Polar Lander beamed to Earth from 157 million miles away. The sites will contain weather reports, science data, first sound clips ever beamed to Earth from "out there" and lots of pictures.
Main Mars site will post the latest pictures and updates throughout the 90-day mission: http://www.jpl.nasa.gov/msp98
JPL's main page has links to the latest Mars project as well as to probes sent to other planets over the last 20 years:
http://www.jpl.nasa.gov
JPL's Mars Educational site which includes activites for children and teachers:
http://marsnt3.jpl.nasa.gov/education/index.html
UCLA, where the primary science team is based, offers a site focusing on the experiments aboard the Mars Volitiles and Climate Surveyor payload.
http://mars.ucla.edu
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 20 of 1087: Marcia (MarciaH) * Thu, Dec 2, 1999 (14:33) * 7 lines
The first link (jpl.nasa.gov/msp98) does not work...try
http://mars.jpl.nasa.gov/msp98
or
http://marslander.jpl.nasa.gov
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 21 of 1087: Maggie (sociolingo) * Fri, Dec 3, 1999 (18:10) * 1 lines
Got through to the site OK. Pictures taking a while to download. Will check back again tomorrow as it's getting late here. Looks exciting. Thanks for bringing it to my attention Marcia!!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 22 of 1087: Marcia (MarciaH) * Fri, Dec 3, 1999 (18:18) * 1 lines
Tomorrow will be early enough...JPL are having problems contacting the little dear now that it is on the surface. There are just so few windows of opportunity when Mars is accessible from Earth, and most of those have been used for today. Tomorrow will be a good time to check. It will be slow-going until the weekend begins because all of the schools in America as well as the rest of the world are trying to access the sites, too. It is difficult to be patient...
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 23 of 1087: Marcia (MarciaH) * Fri, Dec 3, 1999 (19:14) * 36 lines
Friday - 18:54 12/03/99, EST
Mars Lander Misses First Communications
Chance
PASADENA, Calif. (Reuters) - Scientists plotting the planned touchdown of
the Mars Polar Lander were met with a frustrating silence on Friday after
failing to receive the first expected signal from the spacecraft that would
indicate that it had landed safely on the Martian surface.
Flight controllers at NASA's Jet Propulsion Laboratory in Pasadena scanned
the skies for contact from the lander, which had been due at roughly 12:39
p.m. PST (3:39 p.m. EST), or 24 minutes after its scheduled landing on Mars.
After about 20 minutes, however, flight operations manager Sam Thurman told
engineers to take a break and wait for the next possible communications
window, expected after 2:04 p.m. PST (5:04 p.m. EST).
Scientists speculated that the spacecraft may have gone into a ``safe'' mode
and had not deployed its main antenna properly after landing. They said
another possibility was that it was transmitting, but on an unknown frequency
that would take NASA's Deep Space Network of worldwide listening posts
some time to locate.
If everything had gone according to plan, the lander would have deployed its
main antenna and started sending back communications to Earth, informing
controllers that it had started its mission to search Mars for signs of water
and other information about its climate.
Scientists long had cautioned that it was very possible that no
communications link would be established during the first window of
opportunity, and said there were numerous chances later on Friday and over
the rest of the weekend for the lander to open communications links with
Earth.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 24 of 1087: Maggie (sociolingo) * Sun, Dec 5, 1999 (17:48) * 1 lines
Now seems a bit dismal. News at teatime (GMT) was that todays window had passed and hope was fading. Nice pictures on the site though!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 25 of 1087: Marcia (MarciaH) * Sun, Dec 5, 1999 (18:43) * 41 lines
Still No Sign of Life From Mars Lander
PASADENA, Calif. (Reuters) - Space controllers on Sunday failed for a fifth
time in 48 hours to make contact with the Mars Polar Lander since it arrived
on the Red Planet, causing bitter disappointment among the scientists and
raising fears about the mission.
``I'm not pessimistic. But I'm disappointed. I feel like I've been stood up on a
date. This is not a good thing,'' Dave Crisp, a mission scientist, told reporters
minutes after the latest attempt failed.
The $165 million lander was supposed to use its Ultra High Frequency
antenna to make contact with the Mars Global Surveyor satellite orbiting the
planet during a brief, six-minute communications window, but it remained
silent, as it has since Friday, when it was scheduled to land on Mars at 3
p.m. EST (2000 GMT).
The window of opportunity stretched from 10:50 a.m. PST (1:50 p.m.
EST/1850 GMT) to 10:56 a.m., but because it takes 15 minutes for a signal
to travel the 145 million miles (232 million km) from Mars to Earth, it was
about 11:15 a.m. before anxious scientists knew their latest attempt had
failed.
It was the first time they had tried to get the craft to use its UHF antenna,
which is not powerful enough to communicate directly with Earth but is
capable of sending a stream of data to the orbiting surveyor for relay to Earth.
The hope had been that if the craft's main antenna, which scientists had been
using for previous attempts to get in touch with the lander, had failed for some
reason, then the UHF might succeed as a backup.
A NASA official at the Jet Propulsion Laboratory in Pasadena said the latest
failure eliminated the possibility that the craft was in a normal operating
mode.
He said the spacecraft may have landed in a pit and that there were objects
blocking the antenna's view of Earth or the surveyor satellite, or it might be
unable to perform gyro compassing to determine its geographical location at
Mars' south pole, he said.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 26 of 1087: Marcia (MarciaH) * Sun, Dec 5, 1999 (18:47) * 1 lines
Cosidering how lame the excuses for the loss of the last Mars Probe were, it would behoove NASA and JPL to get their acts together lest the tax-payers get really unhappy and cut off their allotment!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 27 of 1087: Marcia (MarciaH) * Fri, Dec 17, 1999 (14:08) * 20 lines
This year will be the first full Moon to occur on the winter solstice,
Dec.22 (commonly called the first day of winter) in about 100 years. Since
a full Moon on the winter solstice occurred in conjunction with a lunar
perigee (point in the Moon's orbit that is closest to Earth) the Moon will
appear about 14% larger than it does at apogee (the point in its elliptical
orbit that is farthest from the Earth). And since the Earth is also several
million miles closer to the Sun at this time of the year than in the
summer, sunlight striking the Moon is about 7% stronger making it brighter.
Also, this will be the closest perigee of the Moon this year since the
Moon's orbit is constantly deforming. If the weather is clear and there is
snow cover where you live, it is believed that even car headlights will be
superfluous. On December 21, 1866, the Lakota Sioux took advantage of this
combination of occurrences and staged a devastating retaliatory ambush on
soldiers in the Wyoming Territory. In laymen's terms it will be a super
bright full Moon, much more than the usual AND it hasn't happened this way
for 133 years! Our ancestors, 133 years ago, saw this. Our descendants 100
or so years from now will see this again. I hope someone else might find
this interesting! Remember this will happen December 22, 1999.....
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 28 of 1087: Marcia (MarciaH) * Mon, Dec 20, 1999 (00:29) * 3 lines
The Space Suttle is back in orbit. Lucie watched the blast off from her home:
The shuttle launch was spectacular tonight, I just walk down to the end of my stree and look to the east across the lake and watch it light up the sky and the lake. It's relly beautiful to see. One time the atomspheric condition were just right and about four or five minutes after it went and we were still watching it streak across the sky we heard a rumble, rumble, rumble and the ground started to shake just like it does when you are there. Ilike the night launches because it is so beautiful. The day
ones we can see it but son't get the color. The best thing about that night was a 10 year old girl was visiting her grandparents and she had to write a paper about what she saw when she was here. It was a part of the conditions for her getting out of school to come. She thought it was totaly awesome, but then so did I. In all these years of watching them that is the only time it happened.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 29 of 1087: Marcia (MarciaH) * Mon, Dec 20, 1999 (00:34) * 3 lines
closing my italics Here is the Nasa live TV URL
http://www.chron.com/content/interactive/space/missions/index.html
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 30 of 1087: Marcia (MarciaH) * Mon, Dec 20, 1999 (13:39) * 2 lines
For a truly unique way of looking at Earth check:
http://www.discovery.com/cams/planet/planet.html
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 31 of 1087: MarkG (MarkG) * Tue, Dec 21, 1999 (11:43) * 3 lines
Looking forward to the close & bright full moon tomorrow night (and I will be flying, so a fraction closer still). Is the fact that it coincides with the winter solstice relevant, or does that just give us the longest night in which to see it? - oh hang on, just worked it out, this brings the sun as near as possible to brighten the moon. I was thinking how odd that the sun should be nearest the Earth in midwinter (when it's coldest), but of course that's why it's midsummer (& hottest) in the Southern He
isphere, I suppose.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 32 of 1087: Marcia (MarciaH) * Tue, Dec 21, 1999 (11:56) * 2 lines
Bravo. Your line of reasoning is right-on. I checked the moon just before daylight as it was streaming into my room this morning and it was brilliant. I think one could have read the newspaper by it - or at least the headlines! One tends to forget about the tip of the earth out of plumb which makes these unusual circumstances more fascinating. Pop over to Stonehenge and check the shadows falling over the stones and sight between them. I really wish this were possible for you as I would love a live r
port...almost as much as I would like to be doing the live reporting! Happy Solstice Day, Mark!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 33 of 1087: MarkG (MarkG) * Wed, Dec 22, 1999 (03:58) * 1 lines
Sorry I cannot make it to Stonehenge. Even if I could, the stones are now sealed off from the public, and come the solstice you have to brave the hippies New Age Travelers trying to commune spiritually with the Ancient Druids. But maybe my plane will fly over Salisbury Plain, and I'll try and sneak a peek at the moon shadows!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 34 of 1087: Marcia (MarciaH) * Wed, Dec 22, 1999 (11:54) * 18 lines
How lovely that would be - flying over Stonehenge in the moonlight. *sigh*
I agree entirely with you about the hippie ersatz druids reinventing themselves as they go. Makes the archaeologist and historian in my soul revolt.
Another eye-witness of the shuttle launch:
"Had a beautiful sight a few nights ago. The TV had the shuttle
going up on the split screen, so we ran out. Off to the southeast the sky
was turning orangish and getting brighter. Then we could see the torch like
flame coming up . We watched the shuttle go on up, and the separation of the
boosters and two red dots as they fell back down. Then it just went on up
and turned into like a star, it was really bright. We had an exceptional
clear night and they said we could see it for about 18 minutes to the
curvature of the earth. we went back in the house and then we heard the
thunder and rumble of the noise just reaching us. and the windows quivered
enough that we could hear them rattle. Must have headed more north instead
of south like before. But it was neat, hope to go down sometime and see one."
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 35 of 1087: Gi (patas) * Tue, Dec 28, 1999 (15:27) * 1 lines
I was told about the solstice moon but unfortunately the weather has not been cooperating... I'm afraid we're gonna have another New Year's Eve storm :-(
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 36 of 1087: Marcia (MarciaH) * Tue, Dec 28, 1999 (15:37) * 1 lines
Does this involve bone-chilling dampness and driving rain or do things get cold enough to freeze? I am worried about you and these storms.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 37 of 1087: Gi (patas) * Tue, Dec 28, 1999 (15:58) * 1 lines
Only rain and strong winds... But maybe we'll have better weather for friday.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 38 of 1087: Marcia (MarciaH) * Wed, Dec 29, 1999 (17:20) * 1 lines
We gotta stop talking about this out here in other topics...they are worried about you in Geo 14! Did the strong winds do any serious pruning of your trees or your electrical/phone system?
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 39 of 1087: Marcia (MarciaH) * Sat, Jan 1, 2000 (20:50) * 2 lines
anyone who watched the world-wide pollution extravaganza yesterday under the guise of celebratory fireworks must wonder how long it will circle the earth before it falls as something really
nasty...!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 40 of 1087: Ann (Ann) * Tue, Jan 4, 2000 (22:35) * 17 lines
This probably belongs on an astronomy topic, but I didn't see one when I looked at the list of conferences, so here it is.
My question is about the age of the universe/earth.
The universe is currently estimated to be about 13 billion years old.
In that time, stars and galaxies have formed, gone through their life cycles, died, gathered back together as nebulae, then created second and maybe third generation systems.
Assuming the earth is only a second generation conglomeration of matter, then all of the heavier elements on the earth came from the first generation.
Now the earth is estimated to be already about 4 billion years old. That leaves only 9 billion years--or only twice the time the earth has been around--for that first generation to have lived and died and given rise to the second generation.
That doesn't seem like enough time to me! Am I missing something? Were life cycles nebulae and galaxies faster in the early universe? If not, how does the creation of the heavier elements work into the current assumptions on the age of the universe?
And is this taken into account when people estimate the age of the universe? I would think that any theory which did not allow enough time for at least one cycle to complete itself would be rejected on that basis alone. If there isn't time, then the age can not be right. And can we estimate the age of the universe by estimating the length of time it takes for one cycle.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 41 of 1087: Marcia (MarciaH) * Tue, Jan 4, 2000 (22:39) * 10 lines
You found us! Guess I should paste my message here as well as the sunspot gif
I think our estimation of the age of the universe will continue
to be revised upward as we get bigger and better eyes into the past. For just about forever the age of the Universe was
thought not to exceed 5 billion years and wa more likely 4 billion.
Theories are just that...always subject to revision and correction, fortunately!
This Solar image updates automatically:
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 42 of 1087: Wolf (wolf) * Wed, Jan 5, 2000 (22:05) * 1 lines
that solar deal is neato. it makes me think of an egg yolk when you shine a flashlight through the egg.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 43 of 1087: Marcia (MarciaH) * Wed, Jan 5, 2000 (22:17) * 2 lines
Yup! did you see it pulsate? Makes you think your eyes are doing funny things
to your mind...
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 44 of 1087: Marcia (MarciaH) * Mon, Jan 10, 2000 (17:52) * 32 lines
From John Burnett
Findings from a new study provide strong support for one of two
diametrically opposed theories explaining why people perceive the moon on
the horizon as much larger than the elevated moon, a phenomenon known as the
moon illusion. The human ability to perceive an object's size accurately
regardless of its distance, known as "size constancy,"
reflects an innate understanding of the inverse proportion between distance
and size of the image projected on our retinas.
According to the older of the two general explanations for the moon
illusion, we see the horizon moon as bigger because the information
presented by the intervening terrain affects our perception of distance, so
our brains respond as if the moon were closer. Proponents of more recent
explanations for the moon illusion argue that perception of distance follows
from perception of size. They contend that certain factors cause us to
perceive the elevated moon as smaller than the horizon moon and that this
illusory size difference, in turn,
leads to the perception that the elevated moon is farther away. In an effort
to determine whether people perceive the horizon moon as closer or farther
away than the elevated moon, a father-son team of scientists from New York
University and IBM's Almaden Research Center conducted experiments involving
artificial moons projected onto the
actual sky using optics and a computer display.
In the article, they report that people perceive the halfway point between
themselves and artificial horizon moons to be more than four times farther
away than the halfway point between themselves and artificial elevated
moons. They also show that people perceive an artificial moon of constant
size to be smaller when it is moved closer, in keeping with the older theory
of the moon illusion.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 45 of 1087: Marcia (MarciaH) * Tue, Jan 11, 2000 (18:24) * 33 lines
Original Caption Released with Image:
This mosaic of images collected by NASA's Galileo spacecraft on Thanksgiving Day, November 25,1999 shows a fountain
of lava spewing above the surface of Jupiter's moon Io. The active lava was hot enough to cause what the camera team
describes as "bleeding" in Galileo's camera, caused when the camera's detector is so overloaded by the brightness of the
target that electrons spill down across the detector. This shows up as a white blur in the image.
Most of the hot material is distributed along a wavy line which is interpreted to be hot lava shooting more than 1.5
kilometers- (1-mile) high out of a long crack, or fissure, on the surface. There also appear to be additional hot areas below
this line, suggesting that hot lava is flowing away from the fissure. Initial estimates of the lava temperature indicate that it is
well above 1,000 Kelvin (1,300 Fahrenheit) and might even be hotter than 1,600 Kelvin (2,400 Fahrenheit).
These images were targeted to provide the first close-up view of a chain of huge calderas (large volcanic collapse pits).
These calderas are some of the largest on Io and they dwarf other calderas across the solar system. At 290 by 100
kilometers (180 by 60 miles), this chain of calderas covers an area seven times larger than the largest caldera on the Earth.
The new images show the complex nature of this giant caldera on Io, with smaller collapses occurring within the elongated
caldera.
Also of great interest is the flat-topped mesa on the right. The scalloped margins are typical of a process geologists call
"sapping," which occurs when erosion is caused by a fluid escaping from the base of a cliff. On Earth, such sapping
features are caused by springs of groundwater. Similar features on Mars are one of the key pieces of evidence for past
water on the Martian surface. However, on Io, the liquid is presumed to be pressurized sulfur dioxide. The liquid sulfur
dioxide should change to a gas almost instantaneously upon reaching the near-vacuum of Io's surface, blasting away
material at the base of the cliff. The sulfur dioxide gas eventually freezes out on the surface of Io in the form of a frost. As the
frost is buried by later deposits, it can be heated and pressurized until it becomes a liquid. This liquid then flows out of the
ground, completing Io's version of the 'water cycle.'
North is to the upper left of the picture and the Sun illuminates the surface from the lower left. The image, centered at 61.1
degrees latitude and 119.4 degrees longitude, covers an area approximately 300 by 75 kilometers (190-by-47 miles). The
resolution is 185 meters (610 feet) per picture element. The image was taken at a range of 17,000 kilometers (11,000
miles) by Galileo's onboard camera.
The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science,
Washington, DC. JPL is a division of the California Institute of Technology, Pasadena, CA.
This image and other images and data received from Galileo are posted on the Galileo mission home page at
http://galileo.jpl.nasa.gov . Background information and educational context for the images can be found at
http://galileo.jpl.nasa.gov/images/io/ioimages.html.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 46 of 1087: Maggie (sociolingo) * Fri, Jan 14, 2000 (16:14) * 3 lines
Wow!
There was something on the BBC Open University about a Lunar eclipse coming up. V. interesting programme but at 1 am. my attention slips. Didn't catch the date or whether it was only applicable to the UK.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 47 of 1087: Marcia (MarciaH) * Fri, Jan 14, 2000 (17:25) * 1 lines
I shall look it up and post what I find. It will be at new moon, of course.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 48 of 1087: Marcia (MarciaH) * Fri, Jan 14, 2000 (17:31) * 19 lines
http://aa.usno.navy.mil/AA/data/docs/LunarEclipse.html
This page has an eclipse calaulator. I put in my residence for The January 21st lunar eclipse and got the following:
Total Eclipse of the Moon
HILO, HAWAII
o ' o '
W155 05, N19 43
Hawaii-Aleutian Standard Time
Moon's
Azimuth Altitude
h m o o
Moonrise 2000 Jan 20 18:01 69.0 ----
Moon enters totality 2000 Jan 20 18:04.6 69.3 0.5
Middle of eclipse 2000 Jan 20 18:43.5 72.2 8.4
Moon leaves totality 2000 Jan 20 19:22.3 74.8 16.8
Moon leaves umbra 2000 Jan 20 20:25.4 78.5 30.7
Moon leaves penumbra 2000 Jan 20 21:24.1 81.6 43.8
Moonset 2000 Jan 21 07:29 289.7 ----
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 49 of 1087: Maggie (sociolingo) * Sat, Jan 15, 2000 (07:40) * 1 lines
I gather that what will be seen is a darkened moon, possibly reddish colour.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 50 of 1087: Marcia (MarciaH) * Sat, Jan 15, 2000 (14:45) * 1 lines
Yes, I think so, but since it is close to perigee (last month) it should look very close! BTW, that Jan 21 date was by GMT or Zulu time which is midnight in London (Greenwich, actually) which happens at 2pm here in Hawaii. You need to check that calculator and see what time it happens for you where you live. According to the 1806 Jan 20 entering totality will be the day before the baseball game, alas! But better it rain out the eclipse than the ballgame!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 51 of 1087: Marcia (MarciaH) * Sat, Jan 15, 2000 (15:01) * 2 lines
What we see of the moon during an eclipse is the reflected light of the Earth.
It is also a function of how close Earth is to the Sun. It should be pretty bright and orange because I think we are close to perihelion, as well.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 52 of 1087: Alexander Schuth (aschuth) * Sun, Jan 16, 2000 (06:10) * 3 lines
I wonder if that'd be filmeable with the low-sensitivity Super 8 films I use....
Yeah, we read about that in the paper a few weeks ago. Gonna try get pictures (like I tried of the Hale-Bopp comet - uh, like in "Hail the Bop Apocalyse", have the Heaven Gates folks had read too much Ginsberg? - and the sun-thingus-what-was-the-word-for -it before). Gonna see what I'll do.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 53 of 1087: Alexander Schuth (aschuth) * Sun, Jan 16, 2000 (06:14) * 3 lines
Watching old Super 8 movies from the early 70ies, I found that my father had already filmed a solar eclipse (that the word!).
Oh, now it starts to snow... And I got a radio show to do in Frankfurt tonight! Darn, hope driving is good, I still need much time to prepare, and always leave five minutes after last minute...
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 54 of 1087: Maggie (sociolingo) * Sun, Jan 16, 2000 (10:35) * 5 lines
Did anyone see a report about a black hole being discovered 'near' earth - I think 160,000 light years away. Report said it was the size of 30 million of our suns, but the gravitational pull was puzzlingly lower than expected. Report came from Washington, so I expect there's more info in US than the UK.
Excuse me for being stupid - how do I work out my location to use the table on the site you quoted Marcia.
What's the radio show Alexander?
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 55 of 1087: Marcia (MarciaH) * Sun, Jan 16, 2000 (13:16) * 3 lines
What's the radio show and when're you gonna get a tape of it to Terry so we can see you on SpringCam?
The eclipse should en easily photographable if you have timed photography available on your camera. Open the lens as wide as it will go and leave for 30 sec. then one minute then 45 sec....bracket it well and you should have no trouble. Perhaps, if the Moon is unusually dark you may have to leave the shutter open for a few minutes or more.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 56 of 1087: Marcia (MarciaH) * Sun, Jan 16, 2000 (13:18) * 2 lines
As to how to find out your location on that eclipse calculator, I just put
Hilo, HI, USA.... You use Outer Gronkster, Thistleberry, England or whatever..
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 57 of 1087: Maggie (sociolingo) * Sun, Jan 16, 2000 (14:10) * 1 lines
Oh I didn't realise it was that easy - I thought I had to put coordinates in!!!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 58 of 1087: Maggie (sociolingo) * Sun, Jan 16, 2000 (14:17) * 1 lines
Whoops! non-US form is different. It does require degrees north etc. I'll have to get the atlas out to find out where I am!!!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 59 of 1087: Marcia (MarciaH) * Sun, Jan 16, 2000 (19:05) * 1 lines
Whip out the Ordnance Survey maps. I have their atlas if you are having trouble locating yourself with co-ordinates. Just tell me where you are (town wise) and I will go "down the hall and up the stairs" for you!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 60 of 1087: Maggie (sociolingo) * Mon, Jan 17, 2000 (15:54) * 1 lines
Thank you. High Wycombe, Bucks, England
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 61 of 1087: Alexander Schuth (aschuth) * Mon, Jan 17, 2000 (16:16) * 1 lines
(Radio: my monthly appearance as part of the weekly "superstar rotation" show, 2 hours on Frankfurt's Radio X - this one was titled "Respect For Joe Strummer" to honour a great songwriter and creative muscian; we played material from his London '77 band The Clash to his Nov. 99 release with his new band)
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 62 of 1087: Marcia (MarciaH) * Mon, Jan 17, 2000 (18:50) * 3 lines
Fantastic, Alexander! You are not on the Internet as yet, is that correct? I would listen to you read the phone book in a language I do not understand just to listen to your Teutonic/Brit accent.
Maggie, High Wyckcombe is 21° North latitude, and 4.85° West longitude if I am reading this correctly!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 63 of 1087: Marcia (MarciaH) * Mon, Jan 17, 2000 (19:03) * 1 lines
Let's give High Wycombe another try. 51.5 North Latitude and 0.28 West longitude.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 64 of 1087: Maggie (sociolingo) * Tue, Jan 18, 2000 (16:27) * 1 lines
Thanks, let's hope it's not another cloudy night like last time!!!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 65 of 1087: Maggie (sociolingo) * Tue, Jan 18, 2000 (16:31) * 1 lines
I just saw in the paper that iceballs the size of melons have been landing in Spain. I think 11 have landed so far. Various theories have been put forward as to their origin. The main contender seems to be that it is comet debris, although pranksters have not been ruled out. It is curious that no iceballs have landed in France or Portugal, just Spain.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 66 of 1087: Marcia (MarciaH) * Wed, Jan 19, 2000 (13:51) * 43 lines
Lunar Eclipses always happen during FULL moon. I somehow got it messed up with a solar eclipse which does happen during new moon. I stated the opposite on response 47, proving once again that I am not only mortal, but that I should be held accountable for my information. I welcome corrections and clarifying at all times!
For those of you living in the Florida area and especially, Tallahassee, and happen to be FSU fans / alums, this is for you (Thanks, Barbara!) It also contains good information on why the moon is different colors from eclipse to eclipse. From: http://www.tdo.com/news/local/0119.loc.lunar.htm
Lunar eclipse to pass through on Thursday night
Tallahassee's weather is predicted to be ideal for
viewing the eclipse, the last until 2003.
By GERALD ENSLEY
Tallahassee Democrat
Grab your coat and crank up the Pink Floyd: We're all
going to see a dark side of the moon Thursday when a
total lunar eclipse will be visible all over North and
South America.
The eclipse will begin at 9:03 p.m. Thursday and reach
its darkest phase between 11:05 p.m. and 12:22 a.m.
Friday. This is the first total lunar eclipse visible in the United States since
September 1997 -- and the last we'll see again until May 2003.
The weather in Tallahassee should be ideal, if nippy, for eclipse-viewing.
A cold front moving through North Florida is expected to clear out by
Thursday afternoon. Forecasters at the National Weather Service said
temperatures will be in the 40s Thursday night, and it will feel colder
because of a steady breeze. But the sky will be clear.
The event is being billed as one of the most spectacular lunar eclipses in a
decade. The shadow on the moon is expected to be deep orange-red in
color -- much like a sunset. The shadow is also expected to be the most
sharply visible for a lunar eclipse since 1991, when an erupting volcano in
the Philippines (Mt. Pinatubo) saturated the Earth's atmosphere with a film
of ash and dust.
A lunar eclipse is when the Earth passes between the sun and the moon in
such a way as to cast the Earth's shadow across the lunar face. A solar
eclipse, which is more infrequent, occurs when the moon passes between
the sun and the Earth in such a way as to block the sun's light to the Earth.
The shadow the Earth casts on the moon is called the "umbra." The thin
ring of light around the shadow is called the "penumbra."
The Tallahassee Astronomical Society will host a viewing at Lake Ella.
The group will set up telescopes, and members of the club will be
available to discuss the eclipse and other heavenly bodies. During an
eclipse, many faintly seen stars and planets become more visible.
Gerald Ensley has been with the Tallahassee Democrat since 1980. A
former sportswriter, he is now a general assignment reporter and
columnist. He has won more than 20 state and national awards for his
writing.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 67 of 1087: Marcia (MarciaH) * Wed, Jan 19, 2000 (13:55) * 1 lines
Maggie, I saw the bowling-ball-sized hailstones on the Television news this morning and was astounded. They are HUGE!!! I will post the lab reports when they become available.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 68 of 1087: Wolf (wolf) * Wed, Jan 19, 2000 (22:19) * 1 lines
i still haven't seen those. it'll be interesting once they figure out what's going on. makes me think of the crop circles. ooooh, i should include this stuff in paraspring.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 69 of 1087: Wolf (wolf) * Wed, Jan 19, 2000 (22:27) * 18 lines
here's an article on the melon-sized iceballs:
Comet Debris, Not Excrement, Rains on Spain
MADRID (Reuters) - At least ten melon-sized ice balls that have slammed into
Spain in the last week are probably debris from comets, not human excrement as
first suspected, a Spanish scientist said Monday.
Enrique Martinez, head of a team at the Higher Council of Scientific
Investigation studying the phenomenon, said it was first thought that the ice
balls were human excrement ejected from high-flying aircraft.
``But they lack the typical coloring and texture we find in those cases,'' he
said.
A man in southern Spain escaped injury last week when an ice ball eight inches
across weighing nine pounds smashed into his car. A further nine ice balls have since been reported around Spain over the last week.
human excrement? geeze louise. too bad they didn't have any pictures!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 70 of 1087: Wolf (wolf) * Wed, Jan 19, 2000 (22:28) * 1 lines
wait, did you see that? "they lack the typical coloring and texture we find in those [human excrement from aircraft] cases." gross!!!!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 71 of 1087: Marcia (MarciaH) * Wed, Jan 19, 2000 (23:19) * 3 lines
Yup! Those aircrafty objects often drop *stuff* out, but it is usually that bluish-green disinfectant color. These look like snowballs or hailstones (which I am sure they are - NOT human stuff). Thanks for posting the article. Those were the ones they showed on the telly this morning!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 72 of 1087: Lucille Oftedahl (alyeska) * Thu, Jan 20, 2000 (22:32) * 1 lines
Some scientists seemed to think they might be from a meteor but as another pointed out this couldn't be because the heat of the meteor hitting the earths atmosphere would melt any ice.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 73 of 1087: Wolf (wolf) * Thu, Jan 20, 2000 (22:52) * 3 lines
quite true. check out a pic i found while searching the news sites:
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 74 of 1087: Marcia (MarciaH) * Thu, Jan 20, 2000 (22:53) * 1 lines
Yes....they are very large hailstones, I am sure. How they got that big will be interesting to learn. No go outside and look at the moon! It is cloudy here...really cloudy!!!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 75 of 1087: Marcia (MarciaH) * Thu, Jan 20, 2000 (22:54) * 1 lines
Wolfie!! You did it!!! Brava, my dear. *H U G S * wow!!! Thanks oodles and wads for that. How amazing!!!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 76 of 1087: Wolf (wolf) * Thu, Jan 20, 2000 (22:54) * 1 lines
oh, and the lunar eclipse is quite underway. i've tried to get pictures of it at each interval as it enters into totality. fifteen minutes more to go. (am using a regular minolta 35mm so don't expect anything news worthy, but am trying)
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 77 of 1087: Wolf (wolf) * Thu, Jan 20, 2000 (22:55) * 1 lines
the scientist with his hand on his head looking at this thing is classic!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 78 of 1087: Lucille Oftedahl (alyeska) * Thu, Jan 20, 2000 (23:27) * 1 lines
It really is red, very beautiful. This must be what the ancients saw when the said there ws blood on the moon. I have seen many lunar eclipses but none like this
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 79 of 1087: Marcia (MarciaH) * Thu, Jan 20, 2000 (23:41) * 4 lines
Wow!~!! Red! Nrevedr seen a red one...does the moon look like it is suspended between the stars and the earth? It looks more like a sphere during totality
than at any other time. Lovely of you to keep me posted!
Yeah, I loved that guy in the lab coat with his hand on his head. Wolfie, I downloaded it to my files in case you ever need it,
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 80 of 1087: Ginny (vibrown) * Fri, Jan 21, 2000 (00:23) * 7 lines
The lunar eclipse was "snowed out" where I am. I'd love to see your
pictures, Wolf. I got some pictures of the Sept. 26, 1996 lunar eclipse,
which can be seen at http://world.std.com/~vbrown/p_le96.htm.
I also use Minolta 35mm cameras (XG-M and SRT-101); you can still get some
good shots with 'em! I think the most important tools for astrophotography
are a sturdy tripod, and decent lenses.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 81 of 1087: Marcia (MarciaH) * Fri, Jan 21, 2000 (00:49) * 1 lines
Myh son in California with his digital camera came through! Lovely pix and very red!!! Yippee!!!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 82 of 1087: Marcia (MarciaH) * Fri, Jan 21, 2000 (00:49) * 0 lines
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 83 of 1087: Marcia (MarciaH) * Fri, Jan 21, 2000 (01:07) * 1 lines
Ginny! Welcome! How exciting to have a second IRL person posting on Geo. I am so delighted with your eclipse pictures - one which was unavailable out here. It seems you were about the only one I was in contact with who had success. Portugal and Germany both had problems. You have one of the best lenses it would appear and a good sturdy tripod to keep your images sharp. Mahalo! Visit frequently!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 84 of 1087: Marcia (MarciaH) * Fri, Jan 21, 2000 (01:13) * 1 lines
As soon as my FTP works to Spring's hard drive I will post the pictures David took from California. Spectacular! Never saw a red moon - ever! If anyone MUST see them before Terry gets the tarballs back where they belong, I will email some to you...let me know!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 85 of 1087: Marcia (MarciaH) * Fri, Jan 21, 2000 (01:39) * 6 lines
When asked what camera he was using, my son reeplied with the following:
It is a Nikon Coolpix 950 with a x2 telephoto lens which makes my 35 mm
equivalent of 200 mm. Now you know. Thanks for the bragging.
As soon as I can ftp to access.spring.net we can all see them!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 86 of 1087: MarkG (MarkG) * Fri, Jan 21, 2000 (07:46) * 2 lines
Can't wait, Marcia. Clouds obscured the view here in London - and of course today is cloudless, just like the night before was cloudless ... #@éX#£&!!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 87 of 1087: Ginny (vibrown) * Fri, Jan 21, 2000 (11:34) * 3 lines
Thanks, Marcia! I use a 500mm f8 mirror lens with my old Minolta SRT-101 for all my astrophotography pictures. I generally use high-speed color film (800 ASA and 1600 ASA). Dave's pictures from the digital camera came out great! It seems like the digital cameras are really improving.
I also have solar eclipse pictures from 1994 and 1998, and comet pictures up on the same web site. (http://world.std.com/~vbrown under the "Photo Gallery" link)
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 88 of 1087: Wolf (wolf) * Fri, Jan 21, 2000 (12:30) * 1 lines
marcia, e the pics to me and i'll store them at geocities until ftp is up and running again!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 89 of 1087: Marcia (MarciaH) * Fri, Jan 21, 2000 (12:32) * 5 lines
Splendid, Ginny. It is so great to see your posts in here. One day I will take you to my Arthuriana Topic in the Books Conference... Will get to your other eclipse pix shortly...happy me!!!
Mark, Your sentiments echo mine. Bad enough it was cloudy - but it rained hard enough to make listening to myself think just about impossible. Now, please get it over with before this weekend's baseball games, thank you!
As soon as all of the hard drives for Spring are in place in their new homes and I again have access to them, I shall be ftp'ing my son's great photos and posting them for your perusal. Until then all I can do is to hold them up to the monitor....*sigh*
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 90 of 1087: Marcia (MarciaH) * Fri, Jan 21, 2000 (12:36) * 1 lines
THanks, Wolfie, they will be on their way shortly!!!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 91 of 1087: lidya maccarthy (livamago) * Fri, Jan 21, 2000 (12:40) * 2 lines
I am happy to report that the eclipse was gorgeous in Tallahassee; very clear and when it started, the moon was huge! As the article that our gracious host posted said, there was a gathering at Lake Ella (an artificial, small lake a few miles from where I live), but the night was very cold and the sky was so clear that I only had to step out into our balcony to get a wonderful view. I alternated the eclipse with the Pakistan/India cricket match (Pak won!), so it was an eventful night. I went to bed past m
dnight, and it was still on. The red shadow was spectacular and the view of the nightsky something to remember.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 92 of 1087: Marcia (MarciaH) * Fri, Jan 21, 2000 (12:58) * 2 lines
How spectacular. I was also listening to the cricket match (congrats, Pak!) The only thing better than my seeing an eclipse is for others to see it and post their comments. Thanks, Lidya... It must have been a chicken-skin experience. The best ones seem to be in a sparkly clear and cold night sky! Thanks, Dear!
Now, to send Wolfie David's pix so I can post them...
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 93 of 1087: Maggie (sociolingo) * Fri, Jan 21, 2000 (13:22) * 1 lines
Looking forward to seeing the pix as we had a cloudy sky in High Wycombe (England).
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 94 of 1087: Marcia (MarciaH) * Fri, Jan 21, 2000 (13:30) * 1 lines
Yup! Guess if Mark was overcast you were, as well. They will be up ASAP...
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 95 of 1087: Alexander Schuth (aschuth) * Fri, Jan 21, 2000 (15:12) * 8 lines
I didn't get to see anything - overcast and cloudy. Bah!
Wolf, you are my only hope to get to see this.
(Radio: No, Radio X doesn't webcast yet. No budget - it's a members-club broadcaster working of membership dues and donations only. No commercial aspects, no/few public fundings. Crap equipment. Great spirit.)
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 96 of 1087: Marcia (MarciaH) * Fri, Jan 21, 2000 (16:00) * 22 lines
From Moon Dreams:
I saw the whole eclipse! It was beautiful! We had a
perfect cool clear night, not one cloud in the sky. I
used my binoculars for the details. From white to grey
and then the orangy/red border appeared until it was
completely covered by it. With the naked eye it looked
as if it were Jupiter. Those red moon rays have done
their magic on me.
In Dec. we had the closest moon to earth in years I
was in Milan and it was also a clear crisp night.
In Aug. I was in Lake Como during the solar eclipse
and that was a bad experience. We all felt dizzy and
were affected in a negative way.
The lunar eclipse was the complete opposite. :-D
I heard from my friends in London who got up at 3:45am
to watch it but the sky was completely covered with
the usual stark grey clouds and did not see a thing.
I am still moondancing!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 97 of 1087: Wolf (wolf) * Fri, Jan 21, 2000 (20:57) * 5 lines
the eclipse was indeed beautiful. it was cold and our part of the sky was clear as a bell and i think i was able to discern more stars than usual. my pictures stunk (had them developed today). i went out with my binoculars and got a lens full of red moon.
now to david's pics!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 98 of 1087: Wolf (wolf) * Fri, Jan 21, 2000 (20:58) * 1 lines
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 99 of 1087: Wolf (wolf) * Fri, Jan 21, 2000 (20:58) * 3 lines
the above is my fave!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 100 of 1087: Lucille Oftedahl (alyeska) * Fri, Jan 21, 2000 (21:04) * 1 lines
It was so beautiful, red, red with a halo of light.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 101 of 1087: Marcia (MarciaH) * Fri, Jan 21, 2000 (21:28) * 1 lines
Thank you Wolfie! *hugs* How lovely they are! He had trouble seeing it with the naked eye and sent me that picture too - totally black! It was slightly overcase so you see wispy clouds going past the moon... It must have been incredible in a clear sky! Last night with the reports coming in and the pictures, too was about as close as I could get to actually seeing it. Thank you all! Now, to tell his father (who has logged in and can post any time he chooses...) and David as well...*grin*
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 102 of 1087: Maggie (sociolingo) * Sat, Jan 22, 2000 (16:54) * 1 lines
I'm so excited to see the pix, and fed up that we weren't able to see anything here. Thanks.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 103 of 1087: Marcia (MarciaH) * Sat, Jan 22, 2000 (21:52) * 1 lines
I know the feeling...*lol* I am delighted that someone in the family got to see it...and as all good mom's, I would rather he saw it than I if we had to choose.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 104 of 1087: Annette Mercer (laughingsky) * Sun, Jan 23, 2000 (09:26) * 1 lines
Great pics, Wolf! Thanks!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 105 of 1087: Moon Dreams (Moon) * Tue, Jan 25, 2000 (14:30) * 10 lines
This is from the E. Telegraph today. Lost Asteroid is Earth's, new Moon
http://www.telegraph.co.uk/graphics/00/1/25/whubbig.gif>
I think you will enjoy.
http://www.telegraph.co.uk/et?ac=001182080732013&rtmo=kLLZ1JNp&atmo=kLLZ1JNp&pg=/et/00/1/25/whub25.html
I hope the link works. I know Terry is in the middle of moving.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 106 of 1087: Marcia (MarciaH) * Tue, Jan 25, 2000 (14:48) * 1 lines
Love the Eskimo Nebula! What incredible pictures!!! Thanks so much for posting this, Moon (great name for this topic !) I was busy on Geo 14 posting information on "the snow storm of the millennuim" (it is bound to be called something liket that), and had not seen anything about Hubble and the new pictures. Thanks! And, please don't be a stranger!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 107 of 1087: Marcia (MarciaH) * Thu, Feb 3, 2000 (19:02) * 260 lines
John Burnett sent this contribution. It is fascinating!
Can time run backwards?
IN a distant galaxy, a star unexplodes. Just moments ago a shell of tortured
matter was flying together at 30 000 kilometers a second. Now it has become
a star, and the last shreds of glowing debris are being sucked in. With the
explosion undone, the star begins the long journey back to the time when it
will be unborn into the gas and dust of an interstellar cloud.
Is someone running the film backwards for comic effect? Not necessarily. In
a paper published in the last week of 1999, Lawrence Schulman of Clarkson
University in Potsdam, New York dropped a bombshell. He showed that regions
where time flows in the normal direction can coexist with regions where it
flows backwards. There could be places, perhaps even within our Galaxy,
where stars unexplode, eggs unbreak and living things grow younger with
every second.
To understand how time could run backwards, you need to understand why it
has a preferred direction at all. The equations of physics say that
particles of matter don't care what direction time runs in: any interaction
between two particles could happen just as easily in reverse. (Some nuclear
interactions do show a small bias, but no one has found a way to turn this
into an arrow of time.)
But when you have a lot of particles instead of just two, things change.
Messy, disordered states tend to develop from tidier ones. This tendency is
called the thermodynamic arrow of time. Physicists say that entropy-a
measure of disorder-always increases. "It's easy to break an egg, difficult
or impossible to put the pieces back together," says Schulman.
Say the air in a large room is confined in a 1-metre cube in one corner,
then released. It is perfectly possible that, after five
minutes, the air molecules will all be back in the same 1-metre cube.
Perfectly possible but hugely improbable, because there are far more ways to
arrange the individual molecules when they are spread out than when they are
confined. In fact, the most disordered state-in which the air molecules are
spread more or less evenly throughout the room-can be achieved in far more
ways than any other state. "This is the second law of thermodynamics," says
Schulman, "which seals the fate of Humpty Dumpty."
However, argues Schulman, a reverse arrow is perfectly possible: "It's all
down to the 'boundary conditions'-the external constraints imposed on the
system." In the room, the air has to be in the 1-metre cube only at the
start of the five-minute period. There is no constraint on it at the end of
the five minutes-the system can find its own final state.
But say a final condition is imposed. After five minutes, the air molecules
have to be back in the 1-metre cube. On Earth, this is
clearly an artificial situation. But for Schulman, it is perfectly
legitimate to consider such a state of affairs. "There is no reason in
principle why the Universe might not have a future boundary condition
imposed on it," he says.
The future condition would constrain the molecules to follow only a tiny
subset of trajectories, ending up in the 1-metre cube. From our point of
view, time would be running backwards.
But there's an objection to having forward and backward time regions in the
same universe. Surely the arrow of a reverse-time region would be wiped out
by the slightest interaction with a normal-time region, leaving a completely
disordered system with no arrow at all?
Imagine a game of snooker in which the triangle of red balls is struck by
the cue ball and scattered around the table. Now imagine the reverse-time
scenario. For the balls to follow the precise trajectories necessary to
finish in a triangle will take a monumental amount of coordination. The
slightest disturbance will spoil it. Any interaction with a region with
normal time-for instance, the smallest cry of amazement from someone
watching-could vibrate the air, nudge the balls and wreck everything. So the
backward arrow of a reverse-time region would be instantly destroyed by any
interaction with a normal-time region.
Schulman sees a flaw in this idea. The two systems are on an equal footing,
so the reverse-time region is as likely to destroy the arrow of the
normal-time region as vice versa. "All we can say is that if the two regions
interact their arrows will either both be destroyed or both survive."
Most physicists would have put good money on the former possibility. But
Schulman's startling conclusion is that as long as the interaction between
the two regions is weak, both arrows will survive. He bases this claim on a
simple computer model that allows him to set up weakly interacting systems
with opposite arrows of time and see what happens.
Here's how it works. Take a square 1 unit on each side, and add a particle
with coordinates x and y. Move the particle by repeatedly replacing x with x
+ y and y with x + 2y, and discarding any integer parts of the results (so x
and y stay in the range from 0 to 1). The particle will flit about the
square chaotically. "This mimics the essential behaviour of a gas particle,
while being a lot simpler than reality," according to Schulman.
To set up two gases with opposite arrows of time, Schulman imposes
appropriate boundary conditions. In one model gas, the particles start in
one corner of the square and spread out until they are completely
disordered. They have a "normal" arrow of time (that is, the same arrow as
us). In the other, Schulman imposes the final condition that after, say 20
moves, corresponding to 20 time steps, the particles are all in the corner
of the square. This system has a backward arrow of time. Call the
normal-time region Alice and the reverse-time region Bob.
The next step is to let Alice and Bob interact. Schulman tweaks the
coordinates of each normal-time particle according to the coordinates of the
reverse-time test particle, and vice versa.
When Schulman lets both systems run, he finds that neither arrow of time is
destroyed by the other. "All that happens is that Bob adds a bit of noise to
Alice and Alice adds a bit of noise to Bob," says Schulman. The two arrows
of time are remarkably robust.
"I had no idea when I started my work that this would be the outcome," he
says. "The result surprised me as much anyone else." But this surprise, he
adds, comes from a prejudice against future boundary conditions. Once you
are used to the idea of matter having some memory of what we call its
future, it ceases to surprise. From our point of view, the memory of future
organization drags any reverse time region in the direction of increasing
order, despite any small disturbances from our own "normal" region.
The paper has created quite a stir. "This is very cool stuff indeed," says
Max Tegmark of the University of Pennsylvania. At the Technion-Israel
Institute of Technology, where Sculman began this work, Amos Ori agrees.
"Schulman has shown that the consistency of a model with two simultaneous
time arrows can be explored by relatively simple means. This is a very
important observation."
And he has some equivocal support from David Pegg of Griffith University in
Brisbane. "I see no obvious flaw in the calculations
Schulman has done. He makes his case quite well and I am willing to accept
it, at least until convinced otherwise."
Other physicists don't believe that Schulman's computer model is relevant to
the real world. According to Paul Davies of the University of Adelaide, a
real physical system with a backward arrow would be so fantastically
sensitive to an outside influence that it would be easily destroyed.
"Imagine a box of gas with molecular velocities reversed to bring about an
ordered state," he says. "The gravity of a single electron at the edge of
the observable Universe is enough to throw out the motion of a given
molecule by 90 degrees after only 20 or so intermolecular collisions. That's
pretty sensitive."
Crossing the divide
Surprisingly, Schulman does not dispute Davies' point. "He's absolutely
right. But the very set-up of his thought experiment, with
initial conditions only, precludes an opposite-directed arrow," he says. "My
result applies when boundary conditions are imposed at two separate times."
Some might attack the realism of Schulman's interaction, which he admits is
an abstract mathematical one and not related to a real physical force such
as gravity. "Nevertheless, I maintain that the interaction is adequate for
treating the conceptual issue of the effects of future-conditioning," he says.
So could we actually see reverse-time beings if they exist, and maybe even
wave to them? Remarkably, Schulman says yes. Using a theory originally
developed by Richard Feynman and John Wheeler, which treats light waves
travelling in both time directions on an equal footing, he shows that
forward and reverse regions could communicate by light signals.
But communicating with the other side has its dangers. If normal-time Alice
were to see rain pouring out through reverse-time Bob's window, she could
wait until before the rain started and shout to Bob to close his window. "So
did Bob's floor get wet or not?" says Schulman.
Perhaps something intermediate happens which smears out the paradox. "Alice
sees the window open, shouts to Bob but the message gets blurred and Bob
doesn't close the window," says Schulman.
And there's another, more disturbing possibility. "If you impose initial and
final boundary conditions, it may turn out that the events described simply
can't happen," he says. "In mathematical terms, they are simply not a
solution." In other words, we might just be fated not to cause any
paradoxes.
So, how would a reverse-time region arise? Schulman says such regions may
exist for the same inexplicable reason that regions of normal time exist.
But there is one more concrete possibility: perhaps we live in a Universe
whose expansion from a big bang will one day be reversed into a contraction
down to a "big crunch", a sort of mirror-image of the big bang in which the
Universe was born 13 billion years ago. Although the latest cosmological
evidence is against this, the question isn't settled.
In 1958, Thomas Gold of Cornell University argued that the thermodynamic
arrow of time would reverse during the contraction
phase, creating order out of chaos. Gold's reasoning turned out to be
flawed, but in the 1970s, Schulman used his own model to show that the
conclusions were right. As the big bang and big crunch are both highly
ordered (all the matter is in a small volume), thermodynamic arrows of time
should point away from both ends. The arrow of time depends on the expansion
or contraction of the Universe. "Coffee cools because the quasar 3C 273
grows ever more distant," says Schulman.
Of course, if you were alive during a cosmic contraction phase you would see
nothing untoward-you'd have the same arrow as most of the matter in the
Universe, and it would look like expansion (see Diagram). Stepping outside
the Universe, the situation appears perfectly symmetrical; it makes just as
much sense to call either end the big bang or the big crunch.
A bizarre consequence of Schulman's theory is that some reverse-time regions
from a future contracting phase of the Universe could have survived until
today-and could be only a few tens of light years away. "Some bits of the
Universe might have reverse arrows while other bits with forward arrows
might survive well into the contraction phase."
As the "turnaround" time when the Universe's expansion turns into
contraction could be many hundreds of billions of years away, any stars
would have burnt out. Unfortunately, there would be little prospect of
seeing stellar unexplosions or backwards people among such cold stuff. "We
would still feel their gravity, though," says Schulman. "Such reverse-time
matter would have all the attributes of the invisible, or 'dark', matter
thought to make up most of the mass of our Universe."
Colliding arrows
Another possibility is that in the 13 billion years since the big bang most
of the Universe's matter has collided with reverse-time matter from the
future. The result of such collisions would be matter in "equilibrium" with
no time direction. "Once again, it would appear exactly like dark matter,"
says Schulman. Other physicists are skeptical. "I doubt that this has
anything to do with the dark matter problem," says Tegmark.
So what would it be like in a region that is changing its time direction?
Would exploding things suddenly start unexploding? And what would happen to
the minds of beings around at the time? Sadly, it would be rather
undramatic. For a particular area to change its arrow, it would first have
to go through a period of maximum disorder where there could be no stars or
explosions or structured, working minds. But if you survived for long
enough, you might be able to watch the Universe around you starting to
contract, and most of its matter going into reverse.
If all this is getting a bit difficult to stomach, there is a way to test
it-even if we can't spy on a nearby backwards planet. "Things
happening today could be influenced by boundary conditions at the end of the
Universe," says Schulman. What he has in mind are ultra-slow processes.
In the 1970s, John Wheeler of Princeton University suggested observing the
decays of atomic nuclei with ultra-long half-lives, perhaps many tens of
billions of years. The suggestion was that the normal exponential decay
would be modified by exponential "undecay" and that this might actually be
observable in a sample of a few kilograms in the laboratory. Possible
candidates are rhenium-187 and samarium-147, which have half-lives of about
100 billion years.
Unfortunately, Wheeler was too optimistic. For an experiment of a sensible
duration, a few years, say, you'd need roughly the total supply of these
isotopes in the Universe to see deviations from exponential decay.
"A far better bet is galaxy clustering," says Schulman. He believes that the
way galaxies cluster together could be affected by a future contraction
phase. Unfortunately, he has not yet worked out what form this effect might
take.
But over the past few years, a small group of physicists have been claiming
that the Universe has an inexplicable fractal structure. Most cosmologists
disagree, partly because they have no way to explain such a bizarre pattern.
But say there is something in it. Could it perhaps be a memory of the
future?
###
Further reading: Time's Arrows and Quantum Measurement by L. S. Schulman
(Cambridge University Press, 1997)
Author: Marcus Chown
New Scientist issue 5th February 2000
PLEASE MENTION NEW SCIENTIST AS THE SOURCE OF THIS STORY AND, IF PUBLISHING
ONLINE, PLEASE CARRY A HYPERLINK TO : http://www.newscientist.com
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 108 of 1087: Maggie (sociolingo) * Sun, Feb 6, 2000 (11:42) * 9 lines
In the UK Times today:
Found: The hibernation Gene that could send man to the stars!
Scientists have discovered genes for hibernation in humans. The discovery could pave the way for human hibernation of the kind forshadowed for astronauts in the 30 year old film 2001: A pace odessey. Human hibernation would ake ultrlong haul space travel feasible, with crews effectively put to sleep for months, even years, by triggering the hibernation genes that man's distant ancestors used millions of years ago to sleepthrough hostile winters.
The first use of hibernation technology is likely to be in transplant surgery, where donor organs would be preserved on shelves for weeks or months by putting them into a state of deep sleep.
After a five year project, Matthew andrews, associate professor of genetics at North Carolina State University has idenfied two genes - PL and PDK-4 - which appear to mastermind hibewrnation. One stops carbohydrate metabolism ewhich ensures that the glucose that animals have stored in their body from their last meal is preserved for use by the brain and central nervous system. The second gene controls the production of an enzyme that breaks up stored fatty acids, and converts then into usable fats for fuel. As result the animal can tick over on its stored fat. ..... Researchers found the genes can be made to work in similar ways [to animals] in humans.
They also hope to dientify what genesare involved in triggering the loss of body fat, and to find a way of kick-starting the same genes in humans as a way of losing weight.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 109 of 1087: Marcia (MarciaH) * Sun, Feb 6, 2000 (13:00) * 1 lines
Amazing stuff, Maggie. Thanks for posting this. I had no idea!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 110 of 1087: Maggie (sociolingo) * Sun, Feb 6, 2000 (14:37) * 4 lines
I like the idea of the weight loss gene!!!!
Seriously, it could revolutionise space travel and make things possible.
Did you see anything on the newly discovered black hole that's near earth?
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 111 of 1087: Marcia (MarciaH) * Sun, Feb 6, 2000 (15:27) * 1 lines
I have seen nothing. I am off to go a search for information about it. Thanks for the reminder. (If your body stayed the same shape would you care what you weighed? It is just a number and is entirely asbitrary!)
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 112 of 1087: Maggie (sociolingo) * Sun, Feb 6, 2000 (18:02) * 1 lines
I'm just glad I don't have talking scales - numbers have power don't you know!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 113 of 1087: Marcia (MarciaH) * Sun, Feb 6, 2000 (18:54) * 1 lines
Yup! Numbers do have power. Even for the long and willowy sort who wishes she were more horizontally endowed. *sigh* Whoever though up talking appliances had nothing else to think about, obviously. Very weird, Indeed!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 114 of 1087: Maggie (sociolingo) * Mon, Feb 7, 2000 (13:58) * 3 lines
What do you think about talking spaceships? or computers for that matter.
If we were weightless (e.g. in space) would size matter?????
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 115 of 1087: Marcia (MarciaH) * Mon, Feb 7, 2000 (14:28) * 2 lines
Size would have to matter. The smaller the individuals, the more that could be accommodated, I would think. Everything has a load limit and the support system making the air to breathe and food to eat would have to be considered pr capita.
I know of no way to eliminate the mass even if it is weightless!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 116 of 1087: Maggie (sociolingo) * Mon, Feb 7, 2000 (19:08) * 1 lines
Oh what a pity, just think of the airline bags you could take if weight didn't matter!!! Sorry, it's late and I'm feeling goofy.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 117 of 1087: Marcia (MarciaH) * Mon, Feb 7, 2000 (19:52) * 1 lines
When you ship via air freight, the cost for moving it is by the cubic foot, not by weight. Who said life was fair?!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 118 of 1087: Ginny (vibrown) * Tue, Feb 8, 2000 (12:31) * 45 lines
From http://www.skypub.com/news/news.shtml
Tuesday, February 1
New Martian Meteorite
Discovered in California
About 20 years ago, Robert S. Verish was on a
rock-collecting trip in Southern California’s Mojave
Desert. While walking around, he spotted a couple of
dark basaltic rocks. Interested, Verish scooped them
up, took them home, and put them in a box for safe
keeping.
It wasn’t until last October that Verish realized he
stumbled upon a great find. While cleaning, he
noticed that the rocks he collected looked surprising
like meteorites. Excited, he brought samples of each
rock to geochemist Alan Rubin (University of
California, Los Angeles). Rubin confirmed the rocks to
be meteorites and noted the similarity they had to a
Martian meteorite discovered in Antarctica in 1994. "It
was immediately obvious it was similar to Martian
meteorites," says Rubin. "Within two minutes we were
convinced."
"There may be other pieces out there," Rubin notes.
"The problem is we don’t know where 'out there' is. If
we knew specifically where it was, we could look out
there for more."
This find brings the current number of known Martian
meteorites to 14, and the Los Angeles meteorites are
only the second piece of Mars to be found in the
United States. The first, named Lafayette, was
discovered in Indiana in 1931.
Meteorites are known to be of Martian origin largely
for two reasons. First, gases trapped in the rock
match that of the Martian atmosphere. Second, the
rock’s oxygen isotopic ratios are unlike other
meteorites or any Earth rock, but they match the
ratios found on Mars. The rocks were likely ejected
from Mars during a large impact event, making their
way to Earth in less than a million years.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 119 of 1087: Ginny (vibrown) * Tue, Feb 8, 2000 (12:56) * 115 lines
I think this is the black hole Maggie was asking about...
Chandra Finds a "Cool" Black Hole at the
Heart of the Andromeda Galaxy
CXC PR: 00-03
January 14, 2000
Steve Roy
Marshall Space Flight Center, Huntsville, AL
Phone: 256-544-6535
http://www.msfc.nasa.gov/news
Dr. Wallace Tucker
Chandra X-ray Observatory Center
Harvard-Smithsonian Center for Astrophysics, Cambridge, MA
Phone: 617-496-7998
In its first look at the Andromeda Galaxy (M31), NASA's Chandra X-ray
Observatory has found that the gas funneling into a supermassive black
hole in the heart of this galaxy is a "cool" million degrees. This
unexpected result adds one more quirk to the strange behavior
previously observed at the center of M31.
A team of scientists from the Harvard-Smithsonian Center for
Astrophysics, Cambridge, Mass., reported on this observation at the
195th national meeting of the American Astronomical Society in Atlanta,
Ga. The team is led by Drs. Stephen Murray and Michael Garcia, and
includes Drs. Frank Primini, William Forman, Christine Jones, and Ralph
Kraft.
Chandra took its first X-ray picture of the Andromeda Galaxy with the
Advanced CCD Imaging Spectrometer on October 13, 1999. More than 100
individual X-ray sources were seen. One of these sources was at the
previously determined position of the central supermassive black hole,
which has the mass of 30 million suns. With many X-ray emitting stars
in the center of M31 there was a slight chance that one of them might
be at this position just by coincidence. The low temperature of the
suspected central source, as compared to the other sources, gave the
team the clue they needed.
"When we found that what we suspected was the central object was also
anomalously cool, we KNEW we had it– one coincidence might be
believable, but two was too much to ignore!" said Garcia.
While the gas falling into the central black hole is cool, it is only
cool by comparison to the 100 other X-ray sources in the Andromeda
Galaxy. To be detected by an X-ray telescope, the gas must have a
temperature of more than a million degrees. The typical X-ray star in
the Andromeda Galaxy has a temperature of several tens of millions of
degrees. In contrast, the temperature of the supermassive black hole
source is a few million degrees.
The Andromeda Galaxy is our nearest neighbor spiral galaxy at a
distance of two million light years. It is similar to our own Milky Way
in size, shape, and also contains a supermassive black hole at the
center. This central black hole has always been a bit odd when compared
to central black holes in similar galaxies. Based on its X-ray
luminosity, it is much fainter in radio waves than expected.
Such behavior, coupled with Chandra’s discovery of the low temperature
gas, cannot be accommodated by standard models developed for
supermassive black holes in galaxies like the Milky Way and Andromeda.
"The Chandra observation is telling us that an entirely different flow
pattern is operating around the Andromeda black hole," said Dr. Eliot
Quataert, of the Institute for Advanced Study, Princeton, N.J. "This
will require a different class of models than usually considered."
One possibility is that the gas undergoes a large scale boiling motion
which slows down the rate at which gas falls into the black hole.
The best previous X-ray pictures were not sharp enough to clearly
distinguish the X-ray source associated with the black hole in the
center of the Andromeda Galaxy nor did they give information about the
temperature of the source.
"A good analogy might be to say that previous X-ray images were taken
with a slightly out-of-focus black and white camera, while the Chandra
image is taken with a sharp, color camera" said Murray.
Another intriguing feature of this observation is the detection of a
diffuse glow that extends for a thousand light years around the central
region. It is not known if this is due to many individual sources, or
to a hot wind expanding out from the center.
"This is just a first, quick look at our nearest Milky Way analog,"
Murray emphasized. "I expect that our future pictures will lead to more
exciting discoveries in the Andromeda Galaxy."
The ACIS instrument was built for NASA by the Massachusetts Institute
of Technology, Cambridge, and Pennsylvania State University, University
Park.
To follow Chandra's progress, visit the Chandra site at:
http://chandra.harvard.edu/photo/cycle1/0007/index.html
AND
http://chandra.nasa.gov
NASA's Marshall Space Flight Center in Huntsville, Ala., manages the
Chandra program. TRW, Inc., Redondo Beach, Calif., is the prime
contractor for the spacecraft. The Smithsonian's Chandra X-ray Center
controls science and flight operations from Cambridge, Mass.
High resolution digital versions of the X-ray image (JPG, 300 dpi TIFF )
and other information associated with this release are available on the
Internet at: http://chandra.harvard.edu/
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 120 of 1087: Marcia (MarciaH) * Tue, Feb 8, 2000 (13:10) * 3 lines
Ginny! Thanks for these posts and for finding the black hole which I had not had time to search for. I actually spent yesterday hunting up new graphics (and better ones) for the topics in here with great success.
Zowie! Meteorite is number 1 on my wish list. I just need a wee little piece. The closest to anything like that is the tectite David got for me some years ago. I am not all that sure they are ejecta from the moon, but they are very odd-looking rocks, and I am happy to have one.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 121 of 1087: Marcia (MarciaH) * Fri, Feb 11, 2000 (16:39) * 27 lines
Space Shuttle Launched From Florida Complex
CAPE CANAVERAL, Fla. (Reuters) - The space shuttle Endeavour roared off
the launch pad Friday on a long-delayed radar mapping mission that should
produce the best ever three-dimensional images of Earth's surface.
The six-astronaut crew will spend 11 days in space as they bounce radar
signals off cities, fields, mountains and forests, almost everything, in fact,
that shapes the Earth's surface between the polar regions.
As those signals bounce back into space, they will be collected by antennae
aboard the orbiter and at the end of a 197-foot mast deployed from the
shuttle's cargo bay. It is those slightly off-set images, like the ones seen in a
3-D movie or picture, that should make this whole-Earth topographical map
the best ever assembled.
NASA had been trying to launch this mission since September, but technical
glitches and safety concerns kept Endeavour grounded. A launch attempt last
week was scrubbed by cold winds and heavy rain, and mission managers
used the delay to replace a faulty piece of flight hardware that engineers
detected late in the countdown.
``Liftoff of space shuttle Endeavour on a 21st century mission, putting Earth
back on the map,'' said launch commentator Joel Wells as Endeavour sailed
through the clear blue skies above the Kennedy Space Center in Florida. The
launch was delayed by about 20 minutes past its 12:30 p.m. scheduled
launch time for last-minute technical checks.
Once the astronauts have stowed their spacesuits and configured shuttle
systems for orbit, the first major task will be to deploy the radar mast, which
when fully extended will be the longest fixed structure ever to fly in space.
------------------------------------------------------------
Watch it live http://www.ksc.nasa.gov/shuttle/countdown/video/video45m.html
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 122 of 1087: Marcia (MarciaH) * Fri, Feb 11, 2000 (23:07) * 1 lines
I have been watching the Nasa feed all afternoon and watched the antenna which is going to map the world in fine detail operate. I hope you all smiled and looked up every 90 minutes as the shuttle circled the earth. More about this mission will be taken up on http://www.spring.net/yapp-bin/restricted/read/geo/5/new
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 123 of 1087: Ginny (vibrown) * Mon, Feb 21, 2000 (17:32) * 40 lines
From http://dailynews.yahoo.com
Monday February 21 12:40 PM ET
Shuttle Crew Solves Hatch Glitch, Set for Return
By Brad Liston
CAPE CANAVERAL, Fla. (Reuters) - Astronauts aboard the space shuttle Endeavour ended their ambitious Earth-mapping work on Monday and prepared to come home, but not without some last-minute anxiety as they struggled to shut a hatch.
Following a final mapping pass over Australia, the astronauts began to stow their radar gear for Tuesday's scheduled landing, but there was trouble with the 20-story radar deployed just hours after their Feb. 11 liftoff.
Although the 197-foot collapsible truss-structure folded easily into its canister in Endeavour's cargo bay, three latches designed to secure the canister's hatch refused to lock into place.
The Endeavour astronauts, working remote controls from the orbiter's crew compartment, tried three times to shut the lid before finally succeeding, using a maximum force setting.
Cheers erupted in Houston's Mission Control Center when ground controllers saw the hatch close successfully in a television feed from the orbiter.
``Excellent job. A little extra work and well worth the effort,'' Mission Control told the astronauts.
If the astronauts had not been able to close the hatch, Mission Control probably would have ordered the astronauts to detonate small explosives that would have tossed the mast and its canister overboard.
Although two of the astronauts were trained to leave the orbiter and repair the mast, NASA discarded that option on Saturday when the space agency ordered an extra nine hours of mapping, using time that had been reserved for the contingency spacewalk.
Tense Moments In Space
The 2-1/2 hours spent on Monday trying to close the latches provided tense moments on the ground and in space.
After one failed attempt, mission commander Kevin Kregel radioed a disappointed assessment: ``It's a little bit closed.''
Even if the mast had been sacrificed, the glitch would not have affected the focus of Endeavour's mission, collecting radar readings that will be used to create the most detailed 3-D surface maps ever assembled.
Since taking flight on Feb. 11, the shuttle has mapped more than 46 million square miles of Earth's land formations, most of it twice. The data was stored on 326 digital cassettes inside Endeavour's crew compartment.
Only about two to three percent of Earth's topography has been mapped in the kind of resolution that NASA hopes to accomplish with this mission.
The U.S. military will be the chief beneficiary. The National Imagery and Mapping Agency, which supplies classified maps for U.S. defense and intelligence agencies, is NASA's primary partner on this flight.
Most of the highest resolution images are likely to remain classified. A lower resolution map, still superior to existing planetary topography images, will be made public. Scientists will be given access to the higher resolution images on a case-by-case basis, NASA said.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 124 of 1087: World Builder (MarciaH) * Mon, Feb 21, 2000 (18:36) * 2 lines
The U.S. military will be the chief beneficiary. The National Imagery and Mapping Agency, which supplies classified maps for U.S. defense and intelligence agencies, is NASA's primary partner on this flight.
You betcha. That's why I was waving and smiling peacefully each time they took my picture. Sheesh! Is anyone surprised?! I have a molten lava flows to sell for your future houselots. Get'em while they're hot!!!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 125 of 1087: World Builder (MarciaH) * Mon, Feb 21, 2000 (18:43) * 3 lines
Most of the highest resolution images are likely to remain classified. A lower resolution map, still superior to existing planetary topography images, will be made public. Scientists will be given access to the higher resolution images on a case-by-case basis, NASA said.
Sorta, need-to-own basis? And, I wanted a new atlas to add to my library. Mine is very old... phooey! (Still have those hot lava flows for ya if you're interested...*grin*)
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 126 of 1087: Ginny (vibrown) * Tue, Feb 22, 2000 (00:15) * 1 lines
I found all that to be very disappointing, too. Our tax dollars support all this, just so the government can turn around and say we don't need to see it?? phooey is right! :-P
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 127 of 1087: World Builder (MarciaH) * Tue, Feb 22, 2000 (11:37) * 1 lines
Dontcha wonder where our right to know and their obsession with being the most powerful begin and end?! Be sure to check on Bechtel. Your Boston dig is just a legit front for a REALLY big deal going on. Years ago, when A Rockefeller was vice president of the US, one of his brothers built the Mauna Kea Beach Resort on the Kona side of this island. When we drove by and my dad saw the Bechtel sign on the construction "shack" he simply uttered the name and fell silent. Those were the days when Scandia laboratories had highly-guarded test facilities high up on Mauna Loa. ...and, my Dad was a Knights Templar and a 33° Mason. Anyone get a connection (not sure I do, but there are those out there nodding!)
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 128 of 1087: Ginny (vibrown) * Tue, Feb 22, 2000 (18:04) * 35 lines
This is an old news story, but I thought it might still be of interest since we were talking about black holes recently. It's really exciting that they are finally starting to find evidence of black holes; they've theorized about supermassive black holes at the centers of galaxies for more than a decade!
New evidence of black hole at Milky Way's center
January 7, 1998
Web posted at: 10:03 p.m. EST (0303 GMT)
WASHINGTON (CNN) -- A massive black hole, with a mass 2.6 million times that of the sun, sits at the center of our Milky Way galaxy, providing its gravitational anchor, according to new evidence unveiled by astronomers Wednesday.
Research teams in Germany and the United States found that some stars near the black hole, named Sagittarius A, are speeding along at more than 600 miles a second -- nearly 2.2 million miles per hour (3.5 million kph).
"This is the strongest case we have yet for a super, massive black hole at the center of the Milky Way," said astronomer Andreas Eckart at a news conference sponsored by the American Astronomical Society. Sagittarius A is about 26,000 light years from our sun and the planets that revolve around it. A light year is about 6 trillion miles (9.6 trillion km).
A black hole is an entity of such density and gravitational strength that nothing -- not even light -- can escape from its grasp. Because it doesn't reflect light, a black hole cannot be seen and can only be detected by measuring the motion of stars, gas and dust nearby.
The theory that a black hole exists in the center of the Milky Way -- the galaxy in which Earth is located -- has long been controversial, and many astronomers have rejected previous evidence supporting such a theory.
But researchers at Wednesday's news conference said the latest data bolsters the idea of a black hole because that is the best explanation for their findings.
Astronomers at the Harvard-Smithsonian Center for Astrophysics used radio telescopes to make independent measurements of the motion of the object at the center of the galaxy. They found that it stood relatively still compared to the rest of the galaxy -- which is consistent with a black hole.
Another team of researchers at the Max Planck Institute for Extraterrestrial Physics in Germany found that thousands of stars existed in the area around the black hole, zipping around in tight circles. In order to cause stars to move that quickly, the black hole would have to have 2.6 million times as much mass as our sun.
Many of the stars zipping around Sagittarius A are old -- "a retirement village for stars," says Eckart -- suggesting that the black hole grows more and more massive by sucking in stars over the eons and eventually swallowing them.
Astronomers also unveiled evidence of another unusual black hole, nicknamed Old Faithful, about 40,000 light years from Earth.
Old Faithful, more powerful the Sagittarius A, sucks matter into a doughnut-like disk, then ejects it in eruptions that throw out an amount of material as massive as Mount Everest at a speed of more than 171,000 miles per second (274,000 km per second.)
"It's incredibly violent," said Steven Eikenberry of the California Institute of Technology. "We're talking about something that is trillions of times the annual energy output of the United States."
And when the black hole is active, these eruptions take place in consistent 30-minute intervals. Those regular eruptions led NASA scientists to nickname the black hole after the Old Faithful geyser in Yellowstone National Park, which also erupts regularly.
Reporter Rick Lockridge and Reuters contributed to this report.
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 129 of 1087: World Builder (MarciaH) * Tue, Feb 22, 2000 (19:41) * 1 lines
I really appreciate your posting that article, Ginny. I kept missing it and forgetting to look it up. Now it is here...! You cannot imagine how happy I am in this little conference of mine lately. My favorite stuff being discussed by the greatest posters anywhere. Mahalo nui loa!
Topic 24 of 99 [Geo]: Beyond Planet Earth
Response 130 of 1087: Marcia (MarciaH) * Sat, Mar 4, 2000 (14:46) * 16 lines
Today in Space
4 Mar 2000 Aurora Watch: An