Sandy/NASA Chat Host: . . . . Wed, Feb 26, 9:00AM PDT (-0700 GMT) Welcome
Everyone! Today's Mars Team Online WebChat expert is Jim Murphy. As a
meteorologist and researcher, Jim's work consists of developing computer
models of the martian atmosphere, as well as analyzing data from past
spacecraft missions to Mars and participating in upcoming missions to
Mars. Jim's current plans are to to study the weather data sent back by
the Mars Pathfinder from the surface of Mars. Jim also manages the Wind
Tunnel at NASA's Ames Research Center where he works. Welcome Jim!
jim murphy/nasa: Good morning Sandy, and good morning or afternoon or
evening, whichever is appropriate, to the rest of you...
vince/boeing: Hi Jim, Awhile back I saw a photo in a magazine of a 'dust
devil' on the martian surface (viking Orbitor?) Are these a common occurance?
Do they show up in your computer modeling?
jim murphy/nasa: vince/boeing - Yes, dust devils do appear to be a common
occurrence on Mars. They were seen in Viking orbiter pictures, and thought
to have been 'seen' in Viking lander meteorology data. I include such
a mechanism in my model, but no one has modelled these features yet .
Mike/home: What do you think about the life on mars issue?
jim murphy/nasa: mike - I am not certain about the possible finding
of life on Mars. I do believe that the 'rocks' came from Mars, but I do
not understand enough of the biology issues to have a firm opinion on
wheter or not I beleive the data indicates that life developed there.....future
missions will hopefully help us find more answers.
Tim McCollum/CJHS: Good Morning Jim, Sandy and Andrea - Charleston Jr.
High School in Charleston, IL signing on.
Zsuzsa/Zrinyi Middle Hungary: Hello Sandy.Hello JIM:How strong is the
gravitation on the Mars? How will influence this the rover? How can the
rover move with its 9 kg on the Moon?
jim murphy/nasa: zsazsa/hungary - the gravitation on Mars is about 40%
of the gravity you and I are feeling right now here on Earth. A strong
wind (a really strong one!) might be able to knock the rover over, but
since the riover os so low to the ground, I don't think it will happen.
Zsuzsa/Zrinyi Middle Humngary: What a strong wind can knock over the
jim murphy/nasa: zsuzsa / hungary - the rover can't do much against
a dust storm, but other than possibly making it difficult to see where
the rover os going, dust storms should not affect the rover much (I hope).
John W./CJHS: How do you determine the weather on Mars?
jim murphy/nasa: john W/CJHS - We determine the weather on Mars from
measurements we obtained from the Viking landers and from the Viking orbiters
and Mariner 9 orbiter. We also use computer models, like those used for
forecasting weather here on Earth.
jim murphy/nasa: Anna/Hungary If MGS/Pathfinder, and the 1998 missions
fail, there will be many very sad planetarty scientists. Hopefully, we
would forge ahead with additional missions to get the data we need, but
it is not certain that we would continue....but I think we will be successful.
Zsuzsa/Zrinyi Middle Humngary: How many wind-socks has the Pathfinder
lander? What is the height of them on the weather station bar?
Sandy/NASA Chat Host: Hello to everyone in Hungary! We are so happy
to have you join us again :-)
Sandy/NASA Chat Host: Good Morning Tim and the Rest of Charleston Jr.
High! Glad to see you could join us again :-)
5th grade/Morris: If you could choose only one instrument to a different
planet what would it be?
jim murphy/nasa: 5th grade / morris - If I could choose only one instrument
(and here I assume a meteorology instrument) to send to another planet,
I would send a pressure measuring sensor, since that would provide the
most information about the planet as a whole, rather than just the single
site at which it was measuring.
Levente/Zrinyi/middle/Hungary: I've read in your bio that you want to
be a member of the MPF project. Do you know the result already?
jim murphy/nasa: levente / hungary - Yes, I do know the results of my
application to be a member of the Pathfinder project, and I have been
lucky enough to be selected as a member of the Meteorology instrument
/ science team on tha mission. If somebody asks me what I'll be doing,
i'd love to tell you.
dzsudzsi\Zrinyi(Middle),Hungary: Jim : What do you think, is there any
life on the Mars???
Zsuzsa/Zrinyi Middle Humngary: Jim: Are you waiting for a sand storm
in July during the landing? Can the lander wait for the end of the strom?
What can the rover do against a storm?
jim murphy/nasa: zsuzsa / hungary - Pathfinder lander will not be able
to 'wait out' a sandstorm; the spacecraft goes straight in without going
in to orbit. Luckily Pathfinder is landing at what is probably the least
dusty time of the martian year.
Anna/Zrinyi Middle Hungary: What changes would be needed to use the
rover on the Moon?
Zsuzsa/Zrinyi Middle Humngary: What is the thickness of the sand on
the surface? Can the rover drive on the sand? (It is difficult for a car.)
jim murphy/nasa: Zsuzsa/- yes, it is difficult for a car to dirve in
sand...the rover has speacial wheels to help it drive in the sand, and
the rover is not very heavy (maybe 15-20 pouns) so will not sink to deeply,
and each wheel can be driven by itself so it should be able to get out
of most trouble it muight get in to.
Mike/home: How do you verify your models?
jim murphy/nasa: mike - We verify our models by comparing with data
from Mars; thus, we are very keen on having successful missions so that
we have lost and lots of new data to compare our models to...hopefully
our models are not too far from reality.
Zsuzsa/Zrinyi Middle Humngary: What is the color of the sky on the Mars?
I have seen pictures with blue and orange color, too. Is it depend on
jim murphy/nasa: zsuzsa/hungary - The sky color on mars does depend
on the weather, great point to pick up on !! The martian sky is generally
pinkish/yellowish, dur to the presence at most times of some suspended
dust. If the atmosphere were to be clear of dust (which might sometimes
happen), the sky would be blue, just as it is here on earth, since the
same physical procees which produces the blue sky (light scattering by
molecules) occurs on both planets (really, andy planet with an clear atmosphere).
dzsudzsi\Zrinyi(Middle),Hungary: Jim : But the dunes! Can't they hide
the solar panels?
jim murphy/nasa: dzsudzsi/hyngary - great question about sand affecting
Pathfinder's solar panels. I think that the sand/dust will not be too
much of a problem, since the thickness of the dust layer is small, even
though the dust layer can appear very bright.
Lorien/Dallas: I don't know much about the Martian atmosphere, so: What
elements are in the Martian atmospher, and how are they distributed?
jim murphy/nasa: lorien / dallas - The martian atmosphere is made of
of 95% carbon dioxide (the fizzy stuff in a can of soda), 2-3* nitrogen
(which is 78% of our atmosphere here on earth),,1-2% argon, and tiny bits
of water vapor and other gases. All these gases are reaally well mixed
in the lowwest 100 kilomteres of the atmosphere.
Stacy/Lakeview: Good morning from Washington!
5th grade/Morris: Were you selected on the team from the Pathfinder
if so how many people are on a team?
jim murphy/nasa: 5th grade / morris - Yes, I am selected on the Pathfinder
team. We had a meeting earlier this month, and there are 6 of us on the
meteorology team, and I'd guess about 75-100 on the entire Pathfinder
team (though I am only guessing at this 75-100 number; I'm sure many more
people were involved in building the spacecraft).
Sandy/NASA Chat Host: Welcome 5th grade/Morris. Glad you could join
vince/boeing: How thick (miles) is the atmosphere of Mars?
jim murphy/nasa: vince / boeing - It is difficult to specify a 'thickness'
to an atmosphere...but, to put it in perspective, when the Pathfinder
lander is 150 kilometers (~90 miles) above the surafce of Mars, moving
at ~15000miles per hour, it will start to 'feel' the effects of the atmsophere
and the friction will cause the spacecraft to begin slowing down.
Sandy/NASA Chat Host: Good Morning to Stacy in Washington!
John N/CJHS: Is the weather on Mars anything like the weather on Earth?
jim murphy/nasa: Jon /CJHS - The weater on Mars is like the weather
on earth in that each place on the planet has seasons, in the winter cold
fornmt and warm front type weather features move around the planet, on
a day to day basis it warsm up when the sun rises and cools off when the
sun sets, and so on, so yes, although temperatures are generally colder
than here on earth, and it does not rain on Mars, the weather there is
not too different from here.
Zsuzsa/Zrinyi Middle Hungary: Jim:What new technological and academic
methods had been used at the rover?
Stacy/Lakeview: How do you know that the rock you found in Antarctica
is from Mars?
jim murphy/nasa: stacy / Lakeview - Well, I did not personally find
the rock in Antarctica, but we are quite certain that it came from mars
bacause some gas bubbles trapped inside that rock contained gasey like
those measured in the Mars atmosphere by the Viking landers...good question!
Stacy/Lakeview: What do they think the ice caps are made of?
jim murphy/nasa: Stacy /Lakeview - The ice caps on mars are made mostly
of carbon dioxide, which I mentioned above is the main component of the
atmosphere. There is some water ice at the north pole but apparently much
less or none at the south pole.
Gabe/3rd grade: What will you be doing on the science team?
jim murphy/nasa: gabe/3rd grade & Levente and everyone else - What I
will be doing on the Pathfinder meteorology science team is helping to
decide when weather measurements will be obtained (what times of day,
how frequently,..), producing the wind speed and direction data from the
wind sensor on the lander, and doing scientific analysis of all the meteorolgy
data to see how things vary during the day and seasons....also, I think
I will be having a GREAT TIME !!!
Megan: Would the conditions on mars have any influence upon the experiments?
jim murphy/nasa: Megan - The conditions on Mars have a big influence
on the experiments. Because Mars is so cold, the electronics must be kept
warm, so they are located under the equivalent of a blanket.
Mike/CJHS: What program do you use to make your computer models?
jim murphy/nasa: mike/CJHS - We use the programming langueage FORTRAN
in building our computer models.
Levente/Zrinyi/middle/Hungary: We've seen a film about Mars exploration.
People said: they want to rise the tempeture of the Mars - What do you
think about this problem? Some other questions - Does the wind on the
Mars have an effect to the erosion? Are the seasons similar on the Mars?
Does the Mars have an effect similar as the green-belt effect on the Earth?
jim murphy/nasa: levente / hungary - The wind on Mars has a big effect
on erosion there...but because the wind is much less effective at eroding
than is running water, that is why craters on Mars are much better preserved
(we can still see many of them) than are craters here on Earth (which
has had many crater producing impacts over its lifetime).
dzsudzsi\Zrinyi(Middle),Hungary: Jim : Is the NASA planning to send
people on the Mars? jim murphy/nasa: dzsudzsi / hungary - I am not planning
to send people on theMars (though there are times when my kids are not
being very pleasant when I might wish them to go..), but I think that
in about 30 years or so we aill send the first womaned/manned mission
to Mars...Maybe one of you here today will be on that first rocket ship
to Mars !!!
Lorien/Dallas: Are there any lifeforms on Earth (primitive or otherwise)
that could survive on Mars?
jim murphy/nasa: lorien / Dallas - I do not know if there are any lifeforms
here on Earth which could survive on Mars, but life on Earth exists in
a very, very wide range of conditions, so I would not be surprised if
it is possible...as long as Mars has liquid water somewhere (probably
below the surface).
Jon/Encinal School: Do you use any real Mars rocks or dirt in your models?
jim murphy/nasa: jon / encinal school - I do not use any real Mars rocks
or dirt in my models....my models arereally just numbers on a computer,
with lots and lots of math and physics included in equations, and with
these numbers and equations we calculate what the weather will be like.
Stacy/Lakeview: Is it true that people will be living on Mars in the
21st century? And, who made up Joe the Martian?
jim murphy/nasa: stacy / lakeview - I think that people will be on Mars
in the 21st century, but I don't know if 'living' there is the way to
put it...I guess people will go there fortime period sof 1 or a few years,
like cosmonauts/astronauts now going to the Russian space station.
Levente/Zrinyi/middle/Hungary: A question to Sandy - We couldn't find
anything about webchats after March? Are you going to organize some or
is it over (because we are very happy about these chats)? If yes could
you send us the program?
Sandy/NASA Chat Host: Levente: YES, there will definitely be WebChats
during March. I just haven't finished completing the schedule yet. As
soon as I do, I will post it in the same place the February schedule is
now. This will happen later this week! I'm really happy to hear that you're
enjoying these chats:-) vince/boeing: Can you feed sensor data (pressure)
into a 3d simulation of the weather?
jim murphy/nasa: vince / boeing - Great question - yes, there are ways
to 'feed' measured pressure (and temperature data) into computer simulations
of the weather on Mars...there are a number of people who are working
on this for the upcoming Mars mission, and it is done all the time here
on Earth in forecast models.
Zsuzsa/Zrinyi Middle Hungary: Jim:What will be happen ,if the rover
cannt get out of the Lander? What problem can arise?
Tara/Encinal School: What is your favorite part of your job?
jim murphy/nasa: tara / encinal - My favorite part of my job, in addition
to doing web chats !!, is being able to see a 'problem' or question, deciding
how to go about finding the answer, and then actually doing the work to
find the answer...it really is nice to be able to go from start to finish
having to work out the details yourself (with the help of my colleagues).
5th grade/Morris: Could you give us an average weather report on mars?
jim murphy/nasa: 5th grade / morris - an average weather report on Mars
would be: Here in Chryse Planitia on this fine summer day, morning low
temperatures will start out at 190 Kelvin (minus 117 Fahrenheit), and
after the sun rises will quickly rise, and by early sfternoon will reach
a high temperature of 245 Kelvin (plus 16 Fahrenheit). Winds will be 20-30
miles an hour, and will vary in direction from the southeast in the morning
to being from the northwest in the afternoon.
Jessica/Encinal School: Are you working on any missions for the future?
jim murphy/nasa: jessica / encinal - The missions I am currently working
on (Mars Global Surveyor and Mars Pathfinder ) are both now on their way
to Mars; I do not now have any direct involvement in any future missions.
dzsudzsi\Zrinyi(Middle),Hungary: Jim : How many spacecrafts will the
NASA send to the Mars?
jim murphy/nasa dzsudzs1 / hungary - NASA currently has 2 spacecraft
on the way to Mars; two more are scheduled to be launched in late 1998
/ early 1999, and one or two more in 2001, and also in 2003.
Tim McCollum/CJHS: Thanks Jim, Sandy & Andrea - End of the period at
this end. CJHS signing off. See you next time.
Lorien/Dallas: Are there any telescopes on the Rover, and if so, what
are they being used for?
jim murphy/nasa: lorien / dallas - The rover does nat have any telescopes,
but it does have two cameras which will be used to take pictures of the
lander (which I think will be a really neat picture!) and pictures of
rocks; the rover also has instruments to determine what 'elements' (hydrogen,
helium,, and so on) the rocks and soil and air are made of.
Levente/Zrinyi/middle/Hungary: Can the MPF blown away from the desired
trajectory or kept off by a sandstorm?
jim murphy/nasa: levente / hungary - Pathfinder could have some trouble
getting to its desired location on the surface if there is a big storm
occurring when it arrives, but I think it is very unlikely taht such a
strom will be occurring then.
Mike/home: Jim: Do you think anything could grow on Mars?
jim murphy/nasa: mike / home - I do not think anything (like a tomato)
plant could currently grow on mars, if for no other eason than there is
no liquid water which could be used to water the planets..also, there
are probably not enough nitrients there to sustain a plant (but remember,
you are hearing this from a meteorologist, not a plant/animal person,
so there are better sources of information to answer your question than
Daniel/Zrinyi/middle/Hungary: Hello Sandy! Hello Jim! We have any questions
about the climate of the Mars. Has the Mars any climate? Please, tell
us about it! Excuse me but we can't speak English well.
jim murphy/nasa: daniel / hungary - Certainly, mars has climate. When
we talk about weather, we are usually talking about a certain place on
the planet, say in your city in Hungary or here in Mountain View, CA.
when we talk about an entire planet, we tend to talk in terms of Climate,
which is more like talking about the range of conditions (cold at the
poles, warm at the equator).
Levente/Zrinyi/middle/Hungary: I heard that the MGS has some problems
with its computer. Does it hang on the hardware or is it a bug in the
jim murphy/nasa levente / hungary - Mars Global Surveyor has problem
with one of its solar panels, which did not fully 'deploy' after leaving
Earth's orbit...the MGS folks think that it won't be too much of a problem.
Stacy/Lakeview: How old were you when you started working for NASA?
jim murphy/nasa stacy / lakeview - When I started working at NASA, I
was a 27 year old graduate student; I am now 34, and still getting to
work on a topic I love...I'm a lucky guy.
Levente/Zrinyi/middle/Hungary: The MPF will land by an old river if
I'm right. What is the purpose that the previous missions could find a
lot of frozen water? Where is this water? Does it hang on the Mars' small
gravity or is can it be somewhere below the surface of the Mars?
vince/boeing: Have you been able to tell if land forms...valleys/mountains
affect storm formation or daily weather?
jim murphy/nasa: vince / boeing - Martian landforms do have a significant
effect on storm development and daily weather. Winds blowing up mountain
slopes in the daytime and downslope at night are very common, and may
play a role in generating dust storms. Mountains in the northern hemisphere
apparently do have an effect upon how strong low pressure system (cold
fronts) are as they pass the mountains (like storm developing just east
of the Rocky Mountain here in the USA).
Stacy/Lakeview: How long does it take to get to Mars?
jim murphy/nasa: stacy / lakeview - It takes anywhere from 7 months
to 1-2 years to get to Mars, depending upon how big a rocket is used a,d
the specic type of spacecraft orbit followed to get there...its not like
shooting in a staright line to get there.
dzsudzsi\Zrinyi(Middle),Hungary: Jim : What happend with the Viking-2,
is it still working??
jim murphy/nasa: dzsudzsi / hungary - the Viking landers are no longer
working. I forget the specific reason that Viking lander 2 stopped working
(maybe old age), and Viking lander 1 stopped working, I think, because
the antenna turned the wrong way.
Lorien/Dallas: How is Nasa going to make the enviornment on Mars liveable
for the astronauts (or cosmonauts) in hte manned missions?
jim murphy/nasa: lorien / dallas - When people go to Mars, the will
have to live in enclousers (space habitats) and spacesuits, since the
planet is too inhospitable for you and I to wlak around with protective
Stacy/Lakeview: How many children do you have?
jim murphy/nasa: stacy / lakeview -- I have 3 kids, a 7-year-old daughter
in 2nd grade, a 4 1/2-year old son and an almost 11-month-old son.
Daniel/Zrinyi/middle/Hungary: What kind of special climate elements
are there on the Mars (expect the wind)?
Stacy/Lakeview: What is LGM?
Mike/home: Stacy: LGM means little green men.
5th grade/Morris: Have you worked on any N.A.S.A. missions other than
jim murphy/nasa: 5th grade / morris - I have not worked on any other
missions, except I analyzed some Viking lander meteorology data for my
masters's degree work, and I did have some input for winds to be expected
at the landing sites of the 1996 Russion mission (which unfortunately
failed) and the 1998 NASA Mars lander.
Stacy/Lakeview: Stacy/Lakeview says goodbye for now. It's been fun.
Levente/Zrinyi/middle/Hungary: Is the ash of the vulcanoues blow away
by the winds in relationship with the temperatures (because the atmosphere
is very thin, are the winds able to build an ash layer in the atmosphere)?
Lorien/Dallas: Are there any plans for an astronomy project from Mars?
jim murphy/nasa: lorien / dallas - Great question about an astronomy
plan from mars !! I'm sure people are thinking about such projects (I
know some folks woul;d like such an observatory on the far side of our
Megan: Well, I better be going:) Thanks all for a great chat and see
you next week!
Daniel/Zrinyi/middle/Hungary: What do you think, is this possible to
shape up any life on the Mars?
dzsudzsi\Zrinyi(Middle),Hungary: Jim : How many wind-socks has the Pathfinder
lander? What is the height of them on the weather station bar?
jim murphy/nasa: dzsudzsi / hungary - The Pathfinder lander has 3 wind
socks on the metrorology mast. They are at heights of 0.25, 0.5 and 0.75
meters above the surface and will be seen by the camera, and their tilt
angle and direction will provide information about wind speed and direction,
in addition to Pathfinder's wind sensor which is at the top of the meteorology
mast about 1 meter above the surface..What time is it in Hungary now?
dzsudzsi\Zrinyi(Middle),Hungary: Jim : It's 19:20 the 26th of February,
exactly 9 hours more than in California.
Zsuzsa/Zrinyi Middle Hungary: Sandy and Jim thanks for the answers.By-by.
vince/boeing: Storms on Earth seem to be cyclonic in structure, what
jim murphy/nasa: vince / boeing - Yes, storms on Mars are also cyclonic
in nature. This cyclonic structure results from the spinning of the planet
about its axis, and Mars and Earth spin at almost the same rate (24 hours
for a day on earth, 24 hours and 37 minutes for a day on Mars).
Lorien/Dallas: I've got to go (I volunteer at the Dallas Planetarium
:) But I'll check the archive for the rest of the caht later. Thanks for
dzsudzsi\Zrinyi(Middle),Hungary: JIm : Why doesn't the NASA explore
the two moons of the Mars, Phobos and Deimos?
jim murphy/nasa: dzsudzsi / hungary - There are scientists with NASA
who are interested in exploring the martian moons Phobos and Deimos.
Mike/home: Bye. Thanks for your time and patience. See you at the next
5th grade/Morris: What was your favorite planet when you were growing
jim murphy/nasa: 5th grade/morris - Other than Earth, I guess that my
favorite planet when I was growing up was Mars. You all are much, much
ahead of me when I was your age, since it was not really until late junior
high that i learned much about planets. It was really the Viking landers
landing ion Mars in 1976, when I was 14, that I really became very interested
in Mars, and I'm glad I did !!
Levente/Zrinyi/middle/Hungary: How long is the time limit on the Mars,
when the craters can be recognised (I mean how effective is the erosion
on the Mars)?
Daniel/Zrinyi/middle/Hungary: Is there any systematism in the duststorms
on the Mars?
vince/boeing: Have you been able to corrolate your simultions with hubble
telescope images.... Dust storms etc?
Sandy/NASA Chat Host: GOOD BYE JIM. Thank you very much for taking the
time to answer all of our questions today. You did a terrific job and
we look forward to having you back again in the future!
jim murphy/nasa: . Hi Sandy, Thanks. This was really enjoyable. I hope
that all those students whom I did not get a chance to answer their questions
will not simply forget their questions, but will look up in magazines,
encyclopedias, the WEB, etc. Since I am sure the answers are for the most
part out there. Have fun with Mars, and wish us luck on our ongoing missions!!
vince/boeing: Jim/Sandy - Thank You very much, when's the next mars
Sandy/NASA Chat Host: Vince: The next webchat will be next week. I haven't
finalized the schedule yet, but will by the end of this week. It will
be posted in the same place the Feb. schedule is. Thanks for participating
today; you had some really good questions! Hope to see you again next
Sandy/NASA Chat Host: Dzsudzsi: Thanks to you and your classmates who
participated in today's WebChat all the way from Hungary. Nine hours ahead
of California means that it's dinner time where you are! Go eat! Hope
to hear from you again next week!!!
dzsudzsi\Zrinyi(Middle),Hungary: Hi Jim! Hi Sandy! See you next time!
Daniel/Zrinyi/middle/Hungary: Dear Jim! Thank you for all the answers.
Levente/Zrinyi/middle/Hungary: I read Sandy's message - so bye Jim,
bye Sandy, bye everyone! I hope you won't get any problems with your fingers...Thanks
for everything, have a nice day. Bye, Levente
vince/boeing: Thanks! This is an excellent forum! I'll be back next