Date: March 27, 1998
Featuring: Jim Bell
Astronomer, Planetary Science
Cornell Univeristy, Ithaca, New York
[ Oran/NASAChatHost - 11 - 11:03:34
Welcome to today's Mars Team Online chat with Jim Bell from Cornell
University! Although Jim studies planets, moons, asteroids and comets
within and outside our solar system, his specialty is Mars. Jim studies
pictures of and data about Mars from telescopes and NASA spacecraft
missions (like the Mars Pathfinder). He tries to learn what the surface
of Mars is like, what it's made of, and how much like Earth it may have
been a long time ago. All of this takes place at Cornell University
in Ithaca, New York, where Jim works.
[ Oran/NASAChatHost - 12 - 11:04:34
RE: [Diana-Diana/Science] are you awnsering
questions now ?
Jim Bell will now answer your questions. Thank you for joining us today.
[ JimBell/CornellU - 16 - 11:07:40
Diana: Many asteroids pass close to the Earth. The one predicted to
pass by in 2028 will not hit the Earth but will pass pretty close. A
good chance for astronomers to study it in detail. -JB
[ JonnasJets-KarenJ.Massey - 15 - 11:07:25 ]
2nd and 6th graders/we have a group question.Do you have any information
about the Big Slam theory?
[ JimBell/CornellU - 17 - 11:08:52
Q15: What's the "Big Slam" theory? Are you referring to the possible
origin of the Moon? -JB
[ JimBell/CornellU - 23 - 11:18:24
RE: [JonnasJets-KarenJ.Massey] We were talking
about the asteroid that might hit the Earth.
I see. Well, asteroids hit the Earth all the time, it's just not that
frequent. A big asteroid WILL hit the Earth again in the future, it
just might not be for 100 years or 1000 years or 1,000,000 years; no
one knows. So "Big Slams" are not just theories: they happen all the
time on the geologic time scale.
[ JimBell/CornellU - 19 - 11:11:34
Hi Mr. Bell. We are first graders from Chancellor Elementary in Pennsylvania.
We are studying space. We would like to ask you why you think it is
important that we study Mars.
Good question! Mars is very much like the Earth: a rocky planet with
an atmosphere and evidence for water in the past. We know life formed
on Earth (we're here!) but did life form elsewhere in the solar system
or the Universe too? Mars may be the best place to try to find out...
that's one reason. There's lots more...
[ JimBell/CornellU - 25 - 11:22:25
RE: [Marsgroup-KarenJ.Massey] How thick is
the crust on Mars? Our group of sixth and second graders has 4 people
The Martian crust is anywhere from 20 to 100 km thick, scientists think.
It varies depending on whether the region of the crust has volcanoes,
deep canyons, or impact craters. --JB
[ JimBell/CornellU - 26 - 11:24:13
RE: [Bryan/NPAA] Jim...yesterday it was stated
in a NASA press release that Cydonia will be a priority target for the
MOC camera. Could you comment on your thoughts regarding the Cydonia
Mars Global Surveyor will map the entire planet eventually, so even
if certain surface areas don't get covered in the next few months of
"special" operations during aerobraking ("special" because they are
bonus measurements that no one thought would be even possible to try),
the whole planet will covered in a year. I'm looking forward to seeing
these features and other interesting geologic landforms imaged in more
detail than the limited Viking data. -JB
[ JimBell/CornellU - 30 - 11:26:42
We did an experiment using steel wool, sand, and water to make a Mars-scape.
The sand turned red like Mars. If there was water on Mars at one time,
how did it get there and what happened to it now?
What a great experiment! You made Mars rust. No one really knows where
all the water is today. There are some theories though: maybe it's all
stored in the polar caps (no one really knows how far these go down
below the "tip of the iceberg" visible on the surface). Maybe the water
escaped to space when sunlight broke it down into hydrogen and oxygen.
Maybe it's all stored underground in aquifers like in the midwest U.S.
It's a mystery that the next round of spacecraft are hoping to solve...
but we might not REALLY know until astronauts go there one day. -JB
[ JimBell/CornellU - 33 - 11:30:02
Mr. Bell, we would like to know if there could have been life on Mars
at one time?
Good question! What do you need for life: you need liquid water, organic
molecules, and a source of heat. There is evidence that liquid water
once flowed on Mars a long time ago (it's can't today, the pressure
and temperature are too low). There is some evidence from the famous
Martian meteorite announced in 1996 that organic molecules may exist
on Mars. They certainly exist on Earth and astronomers have discovered
evidence for them in molecular clouds in space. Finally, Mars has had
volcanoes and impacts, and these are sources of heat. So you can argue
that all the ingredients were there at one time or another.... but did
the "spark" ever ignite? I don't know... -JB
[ JimBell/CornellU - 36 - 11:32:41 ]
RE: [Drakio-KarenJ.Massey] What amount of water was on Mars
at one time?
This is a controversial question. Some astronomers think Mars may have
been half-covered by oceans at one time, meaning there was a lot of
water, perhaps equal to a few kilometers thick if spread around the
whole planet. Others think that the water-carved features were formed
very gradually or sporadically and so small amounts of water were involved,
maybe only a few tens or hundreds of meters globally. Today of course
there are only a few tens of millionths of meters of water in the Martian
atmosphere, and all the rest (how much is unknown) is preserved in the
polar caps. -JB
[ MrsMyers-Mrs.Myers/ChancellorElementary - 37 - 11:32:42 ]
Thank you Mr. Bell for answering our questions. We learned a lot about
Mars. Have a nice weekend.
[ JimBell/CornellU - 39 - 11:34:08
RE: [Ashley/RMS-Ashley/RMS] Hi my name is
Ashley Wyatt. I am hoping to be a Mars Scientist. I've talked to colledges
and serched very hard for all the information. I think that Mars is
the most spectacular thing in this Univerise. -AW
Good for you Ashley! Learn some math, some chemistry, some physics,
some computer science, som engineering, and some biology and you're
ready to study Mars! You're just about the right age to be in the first
group of astronauts, if NASA's plans go through as some of us hope they
[ JimBell/CornellU - 40 - 11:34:39
RE: [Mars2Group-KarenJ.Massey] Have you ever
noticed a comet that was about to hit Earth,and if sowhat was its name
and how big was it? we are study buddies from White Lake School in Fort
[ JimBell/CornellU - 46 - 11:38:40
RE: [Blastoff-KarenJ.Massey] Do you think
there is water under the surface of Mars? We studied your biography
this morning. We have also been looking in books to find information
about Mars to come up with our question. We are from Fort Worth, Texas.
I think there is at least ICE under the surface, which is a form of
water. LIQUID water? I'm not so sure. The way science works, it doesn't
really matter what I think: what really matters is: what are the facts?
There are very few facts about the Mars underground, so most of the
ideas are just speculation. -JB
[ JimBell/CornellU - 47 - 11:40:04
RE: [Ashley-Ashley/RMS] What colledge would
be the best to go to to have the best degree in science? -AW
First: remember that it's spelled "college", not "colledge" ;) There
are THOUSANDS of great colleges in the U.S. and in other countries!
Some argue that the "best" are places like MIT, Caltech, Stanford, Harvard,
Arizona, and of course Cornell at the TOP of the list...
[ Ashley-Ashley/RMS - 51 - 11:42:28 ]
I already wrote to Harvard but I figured that they were more of a Buissness
and Law school. And guess what they want me in their college!!
[ JimBell/CornellU - 53 - 11:43:13
RE: [Bryan/NPAA] Jim...based on the work
of Dr. Tom Van Flandern and other researchers, do you feel there is
a probability "the Face," and other features in the Cydonia region are
I am not familiar with Van Fladron's work but I have seen many of the
Viking pictures and I believe that the strange-looking features in many
places of the planet are the result of some really interesting and wild
geologic processes. Our geologic experience here on Earth doesn't necessarily
prepare us for the geology of other planets. the Viking high resolution
images are quite poor, though, so it's hard to believe ANYONE'S interpretation
of crummy data. That's why I'm really looking forward to the Mars Global
Surveyor's global coverage. -JB
[ Bryan/NPAA - 56 - 11:45:56 ]
Thank you for your response Jim...
[ JimBell/CornellU - 55 - 11:45:05
RE: [Ashley-Ashley/RMS] Is it true that there
is gypsum in Mars rocks so that if you add Martian soil and some water
you could "make enough cement to make a terrestrial Jamestown?
There is weak evidence for minerals like gypsum in Mars soil, but not
in the rocks. Where did you get the cement quote? I had never heard
that one. You should always be cautious about such statements; remember:
we know very little about Mars. We are just learning. -JB
[ Ashley-Ashley/RMS - 66 - 11:54:13 ]
I got the quote from a "Life" magazine. And yes, I know we are just
[ JimBell/CornellU - 57 - 11:46:37
RE: [Bryan/NPAA] Jim...I understand the Cydonia
region is controversial, thus your hesitation to answer questions regarding
the hypothesis put forth, but... I am an art teacher doing a project
involving geometry, and geometric patterns in nature and man-made objects.
Our class has looked at the geometric calculations of the Cydonia region
and find them quite startling. My class is on spring break and wanted
me to ask you: Do you feel the Cydonia region could be artifical?
Bryan: No hesitation. Just a slow WWW connection. My point previously
is that nature is much much more bizzare than humans could ever imagine.
As an artist you no doubt appreciate this. -JB
[ JimBell/CornellU - 59 - 11:50:01
RE: [Meteors-KarenJ.Massey] How many times
does Deimos orbit Mars a day? We are 2 second and 1 sixth grader. We
are questioning you from White Lake School. Thank you for answering
Deimos has an orbit period of about 40 hours. Mars rotates in 24 hours,
so it takes Deimos 1.3 Mars days to orbit the planet. Phobos, the innermost
moon, takes only about 0.4 Mars days to orbit the planet (it spins around
Mars two and a half times each Mars day!) -JB
[ KarenJ.Massey - 62 - 11:52:05 ]
Mr. Bell, Thank you for your time today. This has been a very good experience
for our sixth and second graders. They worked in small groups to determine
questions to send. These chats are great opportunities to connect students
with experts in the field. Thank you for your responses.
[ JimBell/CornellU - 64 - 11:53:26
RE: [Ashley-Ashley/RMS] When do you think
that they will start sending PEOPLE to Mars? OK,I am from Raytown Mo
and I go to Raytown Middle School, Or it used to be called Pittman But
theyv'e changed it.
There are no firm plans, but one possibility is as early as 2015 or
2020. It will be very expensive, and very risky, and the governments
of the world (and taxpayers of the world) have not yet decided that
it's important enough to spend many tens of billions of dollars on.
But some plans are being thought about. -JB
[ JimBell/CornellU - 67 - 11:54:37
RE: [Bryan/NPAA] I do appreciate this Jim,
and feel it is important to keep an objective eye...but data published,
and presented to NASA recently, is very interesting! I would make a
suggestion that you read Dr. Van Flandern and Dr. Carlotto's work on
the area, it is remarkable :) Again...thank you. You should talk to
NASA about that slow WWW connection!
Objectivity is critical. If the work has been published in the peer-reviewed
literature then it needs to be addressed. Let's get some good data and
settle the issue once and for all. -JB
[ Bryan/NPAA - 70 - 11:56:49 ]
The work has been published, and Dr. Van Flandern presented his findings
at the last AAS meeting. I'm surprised you haven't heard of it.
[ Ashley-Ashley/RMS - 68 - 11:56:05 ]
Bye I will study hard till next time!
[ Oran/NASAChatHost - 69 - 11:56:18
Thank you to everyone for joining us for today's chat with Jim Bell
from Cornell University.
[ Oran/NASAChatHost - 71 - 11:56:53
A special thanks to Jim for his time with us online. Please join us
for our next Mars Team Online chat!
[ JimBell/CornellU - 74 - 11:57:33
Thank you all for the great questions! I have to sign off now, but this
has been a lot of fun. Keep up with your studies of the Red Planet!