Sandy/Moderator: . . . . Wed, Nov 20, 8:00AM PDT (-0700 GMT). . . [44 ] Welcome to the fourth "Live From Mars" WebChat. Today's Mars expert is Dr. Jack Farmer from NASA's Ames Research Center, just south of San Francisco, California.

Sandy/Moderator: . . . . Wed, Nov 20, 8:00AM PDT (-0700 GMT). . . [45 ] **IMPORTANT NOTE** There are 20 schools signed up for today's chat and that's A LOT of people!!! There is only ONE Jack Farmer answering ALL of your questions, so please be patient. For right now, please send in only ONE QUESTION PER CLASS until we can see how fast Jack can type. Once his fingers get warmed up, I'll invite you to send in more questions.

Cranbrook: . . . . Wed, Nov 20, 8:00AM PDT (-0700 GMT). . . [46 ] Are we getting through?

Sandy/Moderator: . . . . Wed, Nov 20, 8:01AM PDT (-0700 GMT). . . [47 ] Jack's title is "exobiologist." Exobiology is concerned with the search for life outside of Earth and the effects of extraterrestrial environments on living organisms.

Sandy/Moderator: . . . . Wed, Nov 20, 8:01AM PDT (-0700 GMT). . . [48 ] Cranbrook: Yes! Welcome!

Sandy/Moderator: . . . . Wed, Nov 20, 8:01AM PDT (-0700 GMT). . . [49 ] Jack's current research deals with the origin of stromatolites, which are thin-layered sedimentary structures that are produced by communities of microorganisms. He is also interested in how some of the tiny microbes that create stromatolites become fossils. According to Jack, tiny microfossils have been found in rocks as far back as 3.5 billion years. Question is, how do these tiny creatures get preserved and why?

Sandy/Moderator: . . . . Wed, Nov 20, 8:02AM PDT (-0700 GMT). . . [50 ] By understanding such things we can learn more about the ancient environment of the early Earth, and also improve our chances of finding evidence of ancient life in rocks.

Sandy/Moderator: . . . . Wed, Nov 20, 8:02AM PDT (-0700 GMT). . . [51 ] Good Morning Jack! Joffrey/Peugeot: . . . . Wed, Nov 20, 8:02AM PDT (-0700 GMT). . . [52 ] Hi everyone excuse me I'm late

Jack/NASA: . . . . Wed, Nov 20, 8:02AM PDT (-0700 GMT). . . [53 ] Good Morning!

Sandy/Moderator: . . . . Wed, Nov 20, 8:03AM PDT (-0700 GMT). . . [54 ] Hello Joffrey. Do you have a question for Jack?

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:03AM PDT (-0700 GMT). . . [55 ] Hi everyone excuse me I'm late

5th grade/Morris: . . . . Wed, Nov 20, 8:04AM PDT (-0700 GMT). . . [56 ] Hello from Morris

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:04AM PDT (-0700 GMT). . . [57 ] Yes I'd like to know if terraforming Mars is really possible

Megan: . . . . Wed, Nov 20, 8:04AM PDT (-0700 GMT). . . [58 ] What kind of dating process do you use? Do you use carbon dating?

Jack/NASA: . . . . Wed, Nov 20, 8:04AM PDT (-0700 GMT). . . [59 ] Hi Morris!

peter/spring harbor: . . . . Wed, Nov 20, 8:04AM PDT (-0700 GMT). . . [60 ] Hi

Sandy/Moderator: . . . . Wed, Nov 20, 8:04AM PDT (-0700 GMT). . . [61 ] Jack: Do you believe there are fossil remnants in the Mars meteorite?

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:04AM PDT (-0700 GMT). . . [62 ] Yes I'd like to know if terraforming Mars is really possible

Mark/Inverness: . . . . Wed, Nov 20, 8:04AM PDT (-0700 GMT). . . [63 ] Hi Jack - what do the microbes live on?

Cranbrook: . . . . Wed, Nov 20, 8:05AM PDT (-0700 GMT). . . [64 ] What other kind of scientists do you work with?

peter/spring harbor: . . . . Wed, Nov 20, 8:05AM PDT (-0700 GMT). . . [65 ] Do you belive in UFO

BTES Barre Town VT: . . . . Wed, Nov 20, 8:05AM PDT (-0700 GMT). . . [66 ] Hi we're sixth graders from Barre Town Elementary School in Vt

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:05AM PDT (-0700 GMT). . . [67 ] Yes I'd like to know if terraforming Mars is really possible

Kristi/Spring Harbor: . . . . Wed, Nov 20, 8:05AM PDT (-0700 GMT). . . [68 ] Do you think there was ever life on Venus?

RACHAEL/SRINGHABOR: . . . . Wed, Nov 20, 8:05AM PDT (-0700 GMT). . . [69 ] DO YOU BELIEVE IN U-F-O'S?

Jack/NASA: . . . . Wed, Nov 20, 8:05AM PDT (-0700 GMT). . . [70 ] Back to Joffrey: For those who don't know, terraforming means to make changes in Mars' climate to make it Earth-like. Yes, this is possible, but will probably take hundreds of years once we begin.

Kristi/Spring Harbor: . . . . Wed, Nov 20, 8:06AM PDT (-0700 GMT). . . [71 ] Do You?

Sandy/Moderator: . . . . Wed, Nov 20, 8:06AM PDT (-0700 GMT). . . [72 ] Ok everyone: Hold up on the questions for a minute and let Jack answer the first 7 that have come across...

Jon/Spring Harbor: . . . . Wed, Nov 20, 8:06AM PDT (-0700 GMT). . . [73 ] What area of Mars would you be specifically looking for life on ?

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:06AM PDT (-0700 GMT). . . [74 ] Yes I'd like to know if terraforming Mars is really possible

5th grade/Morris: . . . . Wed, Nov 20, 8:06AM PDT (-0700 GMT). . . [75 ] Why is Mars more suitable for life than the other planets?

Andrew/Spring Harbor: . . . . Wed, Nov 20, 8:06AM PDT (-0700 GMT). . . [76 ] Do you tink there is life in the Universe outside the Solar System?

Becky/ Dodgeville Middle: . . . . Wed, Nov 20, 8:06AM PDT (-0700 GMT). . . [77 ] When we bring back samples what precautions do you take so that something that is dormant will not come to life on earth?Do you test to see if anything is alive?

Charlie, Barre Town: . . . . Wed, Nov 20, 8:07AM PDT (-0700 GMT). . . [78 ] Do you think there could be life on other planets besides Mars

Sandy/Moderator: . . . . Wed, Nov 20, 8:07AM PDT (-0700 GMT). . . [79 ] Good Morning to Barre Town Elementary School in Vt!

Pat /Spring Harbor : . . . . Wed, Nov 20, 8:07AM PDT (-0700 GMT). . . [80 ] Do you bileve in UFO's I'll zap you if you don't answer TELL MMMEEEEEE

Kristi/Spring Harbor: . . . . Wed, Nov 20, 8:07AM PDT (-0700 GMT). . . [81 ] Do you think that there was ever life on Venus?

Gina/Spring Habor: . . . . Wed, Nov 20, 8:07AM PDT (-0700 GMT). . . [82 ] When do you think life died out on Mars

Ryan&Eric/Spring Harbor: . . . . Wed, Nov 20, 8:07AM PDT (-0700 GMT). . . [83 ] What involvement do you have with the Mars program

Morris: . . . . Wed, Nov 20, 8:07AM PDT (-0700 GMT). . . [84 ] Have the molecules that were isolated known to exist on earth

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:07AM PDT (-0700 GMT). . . [85 ] Yes I'd like to know if terraforming Mars is really possible

Angela/Spring Harbor: . . . . Wed, Nov 20, 8:07AM PDT (-0700 GMT). . . [86 ] What do you think the "face" on Mars is?

Sandy/Moderator: . . . . Wed, Nov 20, 8:07AM PDT (-0700 GMT). . . [87 ] HEY EVERYONE! HOLD UP ON YOUR QUESTIONS FOR THE NEXT 5 MINUTES. WE'VE GOT 20 ?'S IN THE QUEUE... thanks :-)

Jack/NASA: . . . . Wed, Nov 20, 8:09AM PDT (-0700 GMT). . . [88 ] Hi Kristi! About life on Venus, there is no evidence of an ancient rock record on Venus today. In fact, the surface is quite young and has been completely resurfaced by volcanic eruptions. But the atmosphere of Venus bears clues of an earlier water-rich environment which may have made life possible. The evidence is in the ratios of hydrogen isotopes (isotopes are different species of the same element that differ only in the number of neutrons in the nucleus. This affects the atomic mass. The hydrogen in Venus' atmosphere is enriched in the heavy isotpoe of hydrogen. This suggests that a whole lot of hydrogen and water were lost to space, and further implies thgere was once water there!

Andrea/ChatHost: . . . . Wed, Nov 20, 8:09AM PDT (-0700 GMT). . . [89 ] Joffery - I think your question has been answered.

Eric/Spring Harbor: . . . . Wed, Nov 20, 8:09AM PDT (-0700 GMT). . . [90 ] We are an Enviromental magnet Middle School from Madison WI

Joey/Spring Harbor Middle: . . . . Wed, Nov 20, 8:09AM PDT (-0700 GMT). . . [91 ] When do you think we will land on Mars? When do you think we will be able to live on Mars?

Pat: . . . . Wed, Nov 20, 8:09AM PDT (-0700 GMT). . . [92 ] you got to be kidding there are no ufo's

Andrew/Spring Harbor: . . . . Wed, Nov 20, 8:10AM PDT (-0700 GMT). . . [93 ] If there was life on Venus, how do you think it died out?

Sandy/Moderator: . . . . Wed, Nov 20, 8:10AM PDT (-0700 GMT). . . [94 ] Joffrey: Jack answered your question in response [70]. Use the scroll back to view it.

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:10AM PDT (-0700 GMT). . . [95 ] Is there any volcanic activity on Mars ?

Sandy/Moderator: . . . . Wed, Nov 20, 8:11AM PDT (-0700 GMT). . . [96 ] ONE QUESTION PER CLASSROOM UNTIL WE GET CAUGHT UP PLEASE. THERE ARE 600 KIDS SIGNED UP!

Kristi/Spring Harbor: . . . . Wed, Nov 20, 8:11AM PDT (-0700 GMT). . . [97 ] Thank You!!

RACHAEL/SRINGHABOR: . . . . Wed, Nov 20, 8:11AM PDT (-0700 GMT). . . [98 ] WHAT DO YOU THINK NASA WILL DO IF THE ROVER GETS STUCK?

Jack/NASA: . . . . Wed, Nov 20, 8:12AM PDT (-0700 GMT). . . [99 ] Hi Jon: With regard to where to look for life on Mars: If we are talking about living organisms, we will need to go into the subsurface to depths of hundreds of meters probably. That's the only place where liquid water is likely to be present today. If we are talking about past life, then we need to find water-deposited sediments in some of the old terranes of Mars.

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:12AM PDT (-0700 GMT). . . [100 ] Sandy my mess is always rebooting I don't know why I'v read the answer in 70

Jack/NASA: . . . . Wed, Nov 20, 8:12AM PDT (-0700 GMT). . . [101 ] Hi Environmental! Welcome.

Kristi/Spring Harbor: . . . . Wed, Nov 20, 8:13AM PDT (-0700 GMT). . . [104 ] Thank You!!

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:13AM PDT (-0700 GMT). . . [105 ] Sandy my mess is always rebooting I don't know why I'v read the answer in 70

Pat: . . . . Wed, Nov 20, 8:13AM PDT (-0700 GMT). . . [106 ] you got to be kidding there are no ufo's

Eric/Spring Harbor: . . . . Wed, Nov 20, 8:14AM PDT (-0700 GMT). . . [107 ] We are an Enviromental magnet Middle School from Madison WI

Andrew/Spring Harbor: . . . . Wed, Nov 20, 8:14AM PDT (-0700 GMT). . . [108 ] If there was life on Venus, how do you think it died out?

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:14AM PDT (-0700 GMT). . . [109 ] Sandy my mess is always rebooting I don't know why I'v read the answer in 70

Sandy/Moderator: . . . . Wed, Nov 20, 8:14AM PDT (-0700 GMT). . . [110 ] Pat: This is a discussion about Mars...

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:14AM PDT (-0700 GMT). . . [111 ] Sandy my mess is always rebooting I don't know why I'v read the answer in 70

Jaime/ Spring Harbor: . . . . Wed, Nov 20, 8:15AM PDT (-0700 GMT). . . [112 ] How will our rovers determine if there is life on Mars?

amanda/spring harbor: . . . . Wed, Nov 20, 8:15AM PDT (-0700 GMT). . . [113 ] If there is life on Mars would a meteor hiting Mars kill what life is on Mars?

Shasta In Redding, CA: . . . . Wed, Nov 20, 8:15AM PDT (-0700 GMT). . . [114 ] Hi from North. CA!!

Eric/Spring Harbor: . . . . Wed, Nov 20, 8:15AM PDT (-0700 GMT). . . [115 ] We are an Enviromental magnet Middle School from Madison WI

Sandy/Moderator: . . . . Wed, Nov 20, 8:15AM PDT (-0700 GMT). . . [116 ] Joffrey: I'm sorry, I don't know what your problem is. Do not hit return, only hit chat.

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:15AM PDT (-0700 GMT). . . [117 ] Sandy my mess is always rebooting I don't know why I'v read the answer in 70

Jack/NASA: . . . . Wed, Nov 20, 8:15AM PDT (-0700 GMT). . . [118 ] Hi Rachel! About stuck rovers... we are doing lots of testing and design of rovers to prevent that from getting stuck. One way to avoid he problem is to make sure the rover does not go into the wrong kind of place. To make a smart rover we have been developing autonomous systems that allow the rover to decide when it is in danger and stop before it gets into trouble. This is especially important on Mars where the time to send and recieve a signal will be 10 minutes or more.

Desi/spring harbor: . . . . Wed, Nov 20, 8:15AM PDT (-0700 GMT). . . [119 ] Do you think we will ever determine if there is life outside our solar system?

Andrew/Spring Harbor: . . . . Wed, Nov 20, 8:15AM PDT (-0700 GMT). . . [120 ] If there was life on Venus, how do you think it died out?

Eric/Spring Harbor: . . . . Wed, Nov 20, 8:16AM PDT (-0700 GMT). . . [121 ] We are an Enviromental magnet Middle School from Madison WI

Rachel/Spring Harbor: . . . . Wed, Nov 20, 8:16AM PDT (-0700 GMT). . . [122 ] Do you believe in life on Mars, why or why not?

Shasta In Redding, CA: . . . . Wed, Nov 20, 8:16AM PDT (-0700 GMT). . . [123 ] How can you tell that on the meteroite that was found on the Earth, that there was possible fossilized evidence of possible life on Mars? Couldnt the evidence foind on that rock been from our planet?

Sandy/Moderator: . . . . Wed, Nov 20, 8:16AM PDT (-0700 GMT). . . [124 ] Good Morning Shasta in Redding and Eric in Spring Harbor. Please only send one question each for the time being as there are about 600 kids participating and only ONE Jack Farmer and he's still warming up his typing fingers :-)

Jon/Spring Harbor: . . . . Wed, Nov 20, 8:16AM PDT (-0700 GMT). . . [125 ] So then is there any evidence of liquid or moisture that has been found ? Possibly near Mars' core area?

Eric/Spring Harbor: . . . . Wed, Nov 20, 8:16AM PDT (-0700 GMT). . . [126 ] When will the Rover land on Mars?

Megan: . . . . Wed, Nov 20, 8:17AM PDT (-0700 GMT). . . [127 ] I think you might have missed my q: What dating system do you use? Do you use carbon dating?

Eric/Spring Harbor: . . . . Wed, Nov 20, 8:17AM PDT (-0700 GMT). . . [128 ] When will the Rover land on Mars?

Matt Pavini: . . . . Wed, Nov 20, 8:17AM PDT (-0700 GMT). . . [129 ] 1)How would we go about terraforming a planet? 2)How long would it take with the given theories?

Pat: . . . . Wed, Nov 20, 8:17AM PDT (-0700 GMT). . . [130 ] Is there any proof of intellegent life forms ever being on mars.

Shasta In Redding, CA: . . . . Wed, Nov 20, 8:18AM PDT (-0700 GMT). . . [131 ] What if a dust storm hit the Mars rover and covered its solar panels with dust, and it couldnt recieve power from the sun, what would the scientists do?

Eric/Spring Harbor: . . . . Wed, Nov 20, 8:18AM PDT (-0700 GMT). . . [132 ] When will the Rover land on Mars?

Pat: . . . . Wed, Nov 20, 8:18AM PDT (-0700 GMT). . . [133 ] Is there any proof of intellegent life forms ever being on mars.

Jack/NASA: . . . . Wed, Nov 20, 8:18AM PDT (-0700 GMT). . . [134 ] Hi Andrew: About life on Venus, If it did develop there it probably died out because of the increasing temperatures that happened because of the Greenhouse effect on Mars. The sun was less luninmous early in the history of the solar system, and has gradually warmed up. As that happened, Venus became a hot-house and lost its water and life, if it was ever there.

: . . . . Wed, Nov 20, 8:18AM PDT (-0700 GMT). . . [135 ] Hi this is from planet earth just wondering how thing are doing

Eric/Spring Harbor: . . . . Wed, Nov 20, 8:18AM PDT (-0700 GMT). . . [136 ] When will the Rover land on Mars?

Nathan/ Dodgeville Middle: . . . . Wed, Nov 20, 8:18AM PDT (-0700 GMT). . . [137 ] If we started raising plants on Mars is it possible to change the aptmosphere to contain enough oxygen for humans to survive?

Andrea/ChatHost: . . . . Wed, Nov 20, 8:19AM PDT (-0700 GMT). . . [138 ] Please everyone - let's try and give Jack a chance to answer more questions before you ask new ones.

Sandy/Moderator: . . . . Wed, Nov 20, 8:19AM PDT (-0700 GMT). . . [139 ] Eric: The rover will land on Mars on July 4, 1997.

Andrew/Spring Harbor: . . . . Wed, Nov 20, 8:19AM PDT (-0700 GMT). . . [140 ] Since the Rover is Remote controled, how long would it take the commands from earth to the rover?

Andrew/Spring Harbor: . . . . Wed, Nov 20, 8:19AM PDT (-0700 GMT). . . [141 ] Since the Rover is Remote controled, how long would it take the commands from earth to the rover?

Jack/NASA: . . . . Wed, Nov 20, 8:20AM PDT (-0700 GMT). . . [142 ] Hi Rachel: About life on Mars. I think there is a very good chance that life developed there. Mars is the most Earth-like planet in the solar system and still has subsurface liquid water today. Wherever there is liquid water there is the chance for life.

Jaime/ Spring Harbor: . . . . Wed, Nov 20, 8:20AM PDT (-0700 GMT). . . [143 ] How will our rovers determine if there is life on Mars?

Andrew/Spring Harbor: . . . . Wed, Nov 20, 8:20AM PDT (-0700 GMT). . . [144 ] Since the Rover is Remote controled, how long would it take the commands from earth to the rover?

Morris Knolls HS: . . . . Wed, Nov 20, 8:20AM PDT (-0700 GMT). . . [145 ] Were the compounds isolated in the meteorite ever found on earth?

Kim Le Gr.4 Worc. MA: . . . . Wed, Nov 20, 8:20AM PDT (-0700 GMT). . . [146 ] Do You ever watch the X files. Do any of them seem real?

Rachel/Spring Harbor: . . . . Wed, Nov 20, 8:20AM PDT (-0700 GMT). . . [147 ] Do you believe in life on Mars, why or why not?

Joffrey/Peugeot: . . . . Wed, Nov 20, 8:21AM PDT (-0700 GMT). . . [148 ] Nathan look at [70]

Jon, Barre Town: . . . . Wed, Nov 20, 8:21AM PDT (-0700 GMT). . . [149 ] What do you think the odds are that there really is life on Mare

Sandy/Moderator: . . . . Wed, Nov 20, 8:21AM PDT (-0700 GMT). . . [150 ] Andrew: It depends where Earth and Mars are in their orbits. But a good number is about 10 minutes.

Cranbrook: . . . . Wed, Nov 20, 8:21AM PDT (-0700 GMT). . . [151 ] If we discover life on Mars, do you think we should colonize the planet anyway?

Sandy/Moderator: . . . . Wed, Nov 20, 8:22AM PDT (-0700 GMT). . . [152 ] HEY EVERYONE: SLOW DOWN AGAIN FOR 5 MINUTES AND LET JACK GET CAUGHT UP! YOUR QUESTIONS ARE AWESOME :-)

Jack/NASA: . . . . Wed, Nov 20, 8:22AM PDT (-0700 GMT). . . [153 ] Hi Pat! There is really no real evidence of intellegent life on Mars. The so-called face on Mars can be easily explained as just another landform, and of course, we now know that the canals on Mars talked about last century were optical illusions.

Andrew/Spring Harbor: . . . . Wed, Nov 20, 8:23AM PDT (-0700 GMT). . . [154 ] Since the Rover is Remote controled, how long would it take the commands from earth to the rover?

Sandy/Moderator: . . . . Wed, Nov 20, 8:23AM PDT (-0700 GMT). . . [155 ] More details on the Mars Pathfinder Rover: It will land on Mars July 4, 1997 in Ares Vallis. The rover's name is Sojourner. Once on Mars it will power up and stand to its full height before it walks down a ramp leading from the lander.

5th grade/Morris: . . . . Wed, Nov 20, 8:24AM PDT (-0700 GMT). . . [156 ] We need to sign off in ten minutes. Is it possible for you to answer our question in this time period?

RACHAEL/SRINGHABOR: . . . . Wed, Nov 20, 8:24AM PDT (-0700 GMT). . . [157 ] WHAT DO YOU THINK NASA WILL DO IF THE ROVER GETS STUCK?

Sandy/Moderator: . . . . Wed, Nov 20, 8:24AM PDT (-0700 GMT). . . [158 ] Andrew: I answered your question in response [150]

Sandy/Moderator: . . . . Wed, Nov 20, 8:25AM PDT (-0700 GMT). . . [159 ] Rachel: PLEASE TURN OFF YOUR CAPS LOCK BUTTON! YOU ARE SHOUTING! thank you

Jack/NASA: . . . . Wed, Nov 20, 8:25AM PDT (-0700 GMT). . . [160 ] Jaime, With regards to rovers and life on Mars, it will be quitye difficult I think for a robotic mission to determine conclusively whether life ever developed on Mars. We think we will be looking for microscopic fossils and evidence of life's chemistry. This will be most conclusively done in labs on earth, and so we have been thinking in terms of sample returns of Mars rocks that can be studied here. But we have to find the right rocks and that is where rovers will be invaluable tools in exploration!

Sandy/Moderator: . . . . Wed, Nov 20, 8:26AM PDT (-0700 GMT). . . [161 ] 5th grade/Morris: Please repeat your question and Jack will answer it.

Kristi/Spring Harbor: . . . . Wed, Nov 20, 8:26AM PDT (-0700 GMT). . . [162 ] Thank You!!

Jack/NASA: . . . . Wed, Nov 20, 8:27AM PDT (-0700 GMT). . . [163 ] Hi Andrew: With regard to commandng a rover from Earth, the time delays between signal commands will depend on where Mars is in its orbit. I think the upcoming missions are planning on 10 minutes or so per command cycle.

RACHAEL/SRINGHABOR: . . . . Wed, Nov 20, 8:29AM PDT (-0700 GMT). . . [164 ] DO YOU BELIEVE IN U-F-O'S?

Gina/Spring Habor: . . . . Wed, Nov 20, 8:29AM PDT (-0700 GMT). . . [165 ] When do you think life died out on Mars

Sandy/Moderator: . . . . Wed, Nov 20, 8:30AM PDT (-0700 GMT). . . [166 ] RACHAEL/ SRINGHABOR: for the LAST TIME, please turn off your CAPS LOCK.

5th grade/Morris: . . . . Wed, Nov 20, 8:30AM PDT (-0700 GMT). . . [167 ] Could a microoranism from Earth surrvive on Mars?

RACHAEL/SRINGHABOR: . . . . Wed, Nov 20, 8:30AM PDT (-0700 GMT). . . [168 ] this computer is messed up i turned the caps off a long time ago

Michael Gr.4: . . . . Wed, Nov 20, 8:30AM PDT (-0700 GMT). . . [169 ] Is there another planet in the solar system called the X planet?

PAM/Montrose: . . . . Wed, Nov 20, 8:31AM PDT (-0700 GMT). . . [170 ] Hi we like all the answers you have

Sandy/Moderator: . . . . Wed, Nov 20, 8:31AM PDT (-0700 GMT). . . [171 ] Thanks Rachel-- it worked :-)

RACHAEL/SRINGHABOR: . . . . Wed, Nov 20, 8:32AM PDT (-0700 GMT). . . [172 ] when did you start to get interested in mars?

5th grade/Morris: . . . . Wed, Nov 20, 8:32AM PDT (-0700 GMT). . . [173 ] Why is Mars more suitable for life than other planets?

PAM/Montrose: . . . . Wed, Nov 20, 8:32AM PDT (-0700 GMT). . . [174 ] What are you studing on mars right now ?

Hannah, Barre Town: . . . . Wed, Nov 20, 8:33AM PDT (-0700 GMT). . . [175 ] If there is live volcanic activity on Mars, is the rover prepared for it. How do temperature conditions affect the rover?

Jack/NASA: . . . . Wed, Nov 20, 8:33AM PDT (-0700 GMT). . . [176 ] Hi Rachel! About UFO's...personally, I have never seen a UFO. I have talked with Carl Sagan about what he thinks (I greatly respect his opinion!), and although he says it would be "laughable arrogance" for us to think we are alone in the Universe, he also points out there is no real scientific evidence for intellegent life elsewhere, or for UFO's. However, such speculation makes for great movies huh?

J.D/spring: . . . . Wed, Nov 20, 8:33AM PDT (-0700 GMT). . . [177 ] Appoxamitly how big is the volcano on Mars

5th grade/Morris: . . . . Wed, Nov 20, 8:34AM PDT (-0700 GMT). . . [178 ] Hi!

RACHAEL/SRINGHABOR: . . . . Wed, Nov 20, 8:34AM PDT (-0700 GMT). . . [179 ] thank you!

Sandy/Moderator: . . . . Wed, Nov 20, 8:35AM PDT (-0700 GMT). . . [180 ] Hello 5th grade/ Morris: Jack has your question now and is typing out his answer this very moment!

Morris: . . . . Wed, Nov 20, 8:35AM PDT (-0700 GMT). . . [181 ] Are any of the compounds isolated from the meteor are existant on earth?????

Morris: . . . . Wed, Nov 20, 8:35AM PDT (-0700 GMT). . . [182 ] Are any of the compounds isolated from the meteor are existant on earth?????

Zartone Gr. 4 Worcester, MA: . . . . Wed, Nov 20, 8:36AM PDT (-0700 GMT). . . [183 ] Dear Jack, We read your biography this morning in class. You have an interesting life. How long do you plan on working for NASA?

Sandy/Moderator: . . . . Wed, Nov 20, 8:36AM PDT (-0700 GMT). . . [184 ] To find out more personal info about Jack and why he does what does and why he loves it soooooo much, please read his very interesting and humorous bio on: button

Shasta In Redding, CA: . . . . Wed, Nov 20, 8:36AM PDT (-0700 GMT). . . [185 ] Will my questions be answered? I have to log off soon....

Jack/NASA: . . . . Wed, Nov 20, 8:36AM PDT (-0700 GMT). . . [186 ] Hi 5th grade Morris! The surface of Mars is to dry for Earth-life. Liquid water is unstable and vaporizes instantly. The ultraviolet radiation is extreme as well and would probably fry microbial DNA unless it had a heavy duty sunscreen. Finally, the Martian surface is red because of peroxide or bleach, which basically destroys organic molecules. So, it seems unlikely. BUt it's also worth noting that when we returned one of the cameras from the moon after 36 months in the vacuum and cold of space, the microorganisms could be brought back to life!

Mark/Inverness: . . . . Wed, Nov 20, 8:36AM PDT (-0700 GMT). . . [187 ] Jack - Megan's question was about dating soils - do you use carbon dating or something else? (She had to leave for school and asked me to send you the question again...)

BTES, Barre Town, VT: . . . . Wed, Nov 20, 8:36AM PDT (-0700 GMT). . . [188 ] In the future do you rthink humans will live on Mare?

Sandy/Moderator: . . . . Wed, Nov 20, 8:38AM PDT (-0700 GMT). . . [191 ] Hi Pam in Montrose: Hang in there... we're trying hard to get everyone's question answered...

Andrea/ChatHost: . . . . Wed, Nov 20, 8:38AM PDT (-0700 GMT). . . [192 ] Pam - Jack is trying to get to as many questions as he can.

Jack/NASA: . . . . Wed, Nov 20, 8:38AM PDT (-0700 GMT). . . [193 ] Hi J.D.: Olympus Mons is the largest volcano in the solar system and its base is the size of the state of texas, while its evelvation rises to more than 20 km!

David/SpringHarbor: . . . . Wed, Nov 20, 8:39AM PDT (-0700 GMT). . . [194 ] How do explain this image? Joffrey/France: . . . . Wed, Nov 20, 8:39AM PDT (-0700 GMT). . . [195 ] You talked about DNA. 20 acids exist for the all-life form on Earth ! But does is mean that life on Mars or anywhere else would use DNA

misty/ Dodgeville Middle: . . . . Wed, Nov 20, 8:39AM PDT (-0700 GMT). . . [196 ] if you put a lot of rocks in a bucket from earth and one from mars could you pick it out?

Sandy/Moderator: . . . . Wed, Nov 20, 8:39AM PDT (-0700 GMT). . . [198 ] David: please DO NOT SEND PHOTOS as classroom computers do not have enough memory to download them and they really slow down our chat process. Remove the photo now!

Sandy/Moderator: . . . . Wed, Nov 20, 8:40AM PDT (-0700 GMT). . . [199 ] Misty: Great question :-)

Andrea/ChatHost: . . . . Wed, Nov 20, 8:41AM PDT (-0700 GMT). . . [200 ] David - We ask that you don't post pictures to the chats - as they slow the download for participants with modem connections. Thank You.

Cranbrook: . . . . Wed, Nov 20, 8:41AM PDT (-0700 GMT). . . [201 ] Salutations guys (and girls) can you tell me if you have any plans to explore the interior of Olympus Mons? If so, what if you discover a hostile life form?

Jack/NASA: . . . . Wed, Nov 20, 8:42AM PDT (-0700 GMT). . . [202 ] Sorry Megan, Guess I missed your question about dating. To date young materials like soils, we usually use the isotopes of Carbon. Specifically, the radioactive isotope called C-14. It has a half-life (the time it takes for half of the C-14 in the sample to break down) of about 5,000 years. We can now measure small enough quantities of C-14 in samples to go back 60,000 years or so. For really old materials we use other isotopes that have much longer half lives.

Zartone: . . . . Wed, Nov 20, 8:42AM PDT (-0700 GMT). . . [203 ] We have to leave now. Could we get just one question answered?

Sandy/Moderator: . . . . Wed, Nov 20, 8:43AM PDT (-0700 GMT). . . [204 ] Zartone: Sorry about that... What is your question?

Jack/NASA: . . . . Wed, Nov 20, 8:45AM PDT (-0700 GMT). . . [205 ] Hi Joffrey: About DNA and life on Mars. WE really do't know the answer to your question, because we only have one example of life so far, namely that here on Earth. We use that as a model, but many of us leave the door open for life to have developed differently on Mars. It would not necessarily have to be DNA-based. It just needs to carry out basic encoding functions and be able to self-replicate. It is probably fair to say it should be DNA-like, a long chained polymer of carbon and other biogenic elements.

PAM/Montrose: . . . . Wed, Nov 20, 8:45AM PDT (-0700 GMT). . . [206 ] What evidence do you have so far

jessica/ Dodgeville Middle: . . . . Wed, Nov 20, 8:45AM PDT (-0700 GMT). . . [207 ] Where on Mars is the best location to look for water?

Zartone gr.4 Worcester, MA: . . . . Wed, Nov 20, 8:46AM PDT (-0700 GMT). . . [208 ] We just want to know if there is a planet called the X planet. Thank you.

BTES, Barre Town, VT: . . . . Wed, Nov 20, 8:46AM PDT (-0700 GMT). . . [209 ] We have a couple of questions that we would like them answered

Andrea/ChatHost: . . . . Wed, Nov 20, 8:46AM PDT (-0700 GMT). . . [210 ] Pam - did you get your questions answered? You may want to try asking it again.

Shasta: . . . . Wed, Nov 20, 8:46AM PDT (-0700 GMT). . . [211 ] Could you answer my question about the Mars Rover and the evidence for life on Mars?????

Shasta: . . . . Wed, Nov 20, 8:46AM PDT (-0700 GMT). . . [212 ] We have to log off.....

PAM/Montrose: . . . . Wed, Nov 20, 8:47AM PDT (-0700 GMT). . . [213 ] What are you studing right now

Jack/NASA: . . . . Wed, Nov 20, 8:47AM PDT (-0700 GMT). . . [214 ] Hi Misty: About telling Earth rocks from Mars rocks...the answer is yes! Mars rocks are quite enriched in sulfur and iron, and we could probably tell that way. But in addition, the isotopes in Mars rocks can be used quite effectively to tell the two apart!

Sandy/Moderator: . . . . Wed, Nov 20, 8:47AM PDT (-0700 GMT). . . [215 ] Zartone: Jack has just seen your question and is typing out his answer to you... stand by :-)

Joffrey/France: . . . . Wed, Nov 20, 8:48AM PDT (-0700 GMT). . . [216 ] Thank you Jack ! So all life need is C, H, O, N.

Sandy/Moderator: . . . . Wed, Nov 20, 8:49AM PDT (-0700 GMT). . . [217 ] BTES, Barre Town, VT: Please send your questions again. But one at a time, so that Jack has some time to answer them. Thanks :-)

Cranbrook: . . . . Wed, Nov 20, 8:49AM PDT (-0700 GMT). . . [218 ] Do you think that we should colonize planets that we know have life on them? If so, do you have any procedures for first-contact with other life-forms?

Mark/Inverness: . . . . Wed, Nov 20, 8:49AM PDT (-0700 GMT). . . [219 ] Thanks Jack. I've passed your answer on to Megan via email.

Jack/NASA: . . . . Wed, Nov 20, 8:49AM PDT (-0700 GMT). . . [220 ] Dear Zartone: Planet X was first suggested on the basis of anomalies in the orbits of the outer planets (Neptune I think), but the interest has since died down as the anomalies have been shown to be measurement errors. As far as I know there is no evidence for a planet X.

BTES, Barre Town, VT: . . . . Wed, Nov 20, 8:50AM PDT (-0700 GMT). . . [221 ] We have a class to go to so could you please answer at least one question.

Jack/NASA: . . . . Wed, Nov 20, 8:51AM PDT (-0700 GMT). . . [222 ] Hi Joffrey: To have life we think we need liquid water, carbon, nitrogen, phosphorus and probably trace nutrients. The liquid water is fundamental!

jessica/ Dodgeville Middle: . . . . Wed, Nov 20, 8:51AM PDT (-0700 GMT). . . [223 ] Do you think we will ever find life larger than microorganisms on Mars?

Cranbrook: . . . . Wed, Nov 20, 8:51AM PDT (-0700 GMT). . . [224 ] We have to go to class also. Will our questions be answered later?

PAM/Montrose: . . . . Wed, Nov 20, 8:51AM PDT (-0700 GMT). . . [225 ] If evidence of life is found by Pathfinder do you Expect to find additicnal life on Mars?

Andrea/ChatHost: . . . . Wed, Nov 20, 8:51AM PDT (-0700 GMT). . . [226 ] BTES - Please ask your questions again.

Sandy/Moderator: . . . . Wed, Nov 20, 8:51AM PDT (-0700 GMT). . . [227 ] BTES: WHAT IS YOUR QUESTIONS?

Zartone: . . . . Wed, Nov 20, 8:52AM PDT (-0700 GMT). . . [228 ] Dear Mr. Farmer, Thank you for answering our question.

BTES, Barre Town, VT: . . . . Wed, Nov 20, 8:52AM PDT (-0700 GMT). . . [229 ] We have been waiting for a half hour for an answer.

Shasta: . . . . Wed, Nov 20, 8:52AM PDT (-0700 GMT). . . [230 ] Well, no answer....We have to go...I wish you couldve gotten to us but thanks

Sandy/Moderator: . . . . Wed, Nov 20, 8:53AM PDT (-0700 GMT). . . [231 ] Cranbrook: Go to the Live From Mars Web Page and you will see how to email your questions in and they will most certainly be answered within a 24-hr. period. button

Mrs.: . . . . Wed, Nov 20, 8:53AM PDT (-0700 GMT). . . [232 ] Do you ever think that we will live on another planet? Pam Smith

Joffrey/France: . . . . Wed, Nov 20, 8:54AM PDT (-0700 GMT). . . [233 ] Can "Hell's cell", mentionned in American scientist, live in the deep ground of Mars ?

Cranbrook: . . . . Wed, Nov 20, 8:55AM PDT (-0700 GMT). . . [234 ] Thanks, We will send questions via email.

Mrs.Efros 4th Grade: . . . . Wed, Nov 20, 8:55AM PDT (-0700 GMT). . . [235 ] How does the weather on Mars compare with Earth? Nicole Havens

Eric/NRAO: . . . . Wed, Nov 20, 8:55AM PDT (-0700 GMT). . . [236 ] How much public outreach do you get to do? Do you miss teaching oceanography (I took the course you co-taught with Dr. Kaplan in the Spring of 1987)? BTW, you're right that there is currently no evidence for a planet X, but the orbit of Pluto is not known to very high precision yet.

Sandy/Moderator: . . . . Wed, Nov 20, 8:55AM PDT (-0700 GMT). . . [237 ] 5 MORE MINUTES...

John Bayne: . . . . Wed, Nov 20, 8:55AM PDT (-0700 GMT). . . [238 ] Hi Jack! If a meteorite similar to the "Mars Rock" was to land on Earth from a different solar system, would it be any more difficult to identify fossils on? If so, why?

BTES, Barre Town, VT: . . . . Wed, Nov 20, 8:55AM PDT (-0700 GMT). . . [239 ] 1950's there was an autopsey done on an alian. True or false?

sandy: . . . . Wed, Nov 20, 8:55AM PDT (-0700 GMT). . . [240 ] I am from mars earthlings how are you

: . . . . Wed, Nov 20, 8:55AM PDT (-0700 GMT). . . [241 ] Hi were from Stillwater minnesota and were studing mars, how long will it take to get to mars and back?

Sandy/Moderator: . . . . Wed, Nov 20, 8:56AM PDT (-0700 GMT). . . [243 ] Stillwater, Minn.: It takes 9 months to get to Mars.

Rachel B./Spring Harbor: . . . . Wed, Nov 20, 8:56AM PDT (-0700 GMT). . . [244 ] What are the chances of humans ever being able to live on Mars?

Mrs.Efros 4th Grade: . . . . Wed, Nov 20, 8:56AM PDT (-0700 GMT). . . [245 ] What are your favorite foods? Jillian White

: . . . . Wed, Nov 20, 8:56AM PDT (-0700 GMT). . . [246 ] how are doing

Mark/Inverness: . . . . Wed, Nov 20, 8:56AM PDT (-0700 GMT). . . [247 ] Thanks to Jack and team for another very interesting Mars chat.

sandy: . . . . Wed, Nov 20, 8:57AM PDT (-0700 GMT). . . [248 ] how are you i am snick

Jack/NASA: . . . . Wed, Nov 20, 8:57AM PDT (-0700 GMT). . . [249 ] Hi Cranbrook: Colonizing a planet with life might not be that straight forward. Remember that the range of conditions that are comfortable for humans is pretty narrow compared to the possible range of life as a whole. Some organisms, for example, can even survive below temperatures of 80 degrees C, while others quickly die in the presence of oxygen. So, colonizing will require us to take our own environment to whatever planet we are talking about. As far as precautions, we do have to worry about protecting the home planet from life that we might find elsewhere, and there is a whole program in NASA that deals with that subject. We are mostly planning around Mars sample return now, and will have to create special facilities to quaratine samples and special procedures for handling those materials when they are returned to Earth. It will be very important to make the right decisions so as to not risk the health of our biosphere and the National Academy of Science has a special panel reviewing this problem right now. I talked to them back in the Spring and this group of immient scientists are doing their best to come up with sound recommendations as soon as possible!

Sandy/Moderator: . . . . Wed, Nov 20, 8:57AM PDT (-0700 GMT). . . [250 ] David: We asked you once not to put up photos because of the time it takes schools to download, DO NOT DO THIS AGAIN! thank you

Joey/Spring: . . . . Wed, Nov 20, 8:58AM PDT (-0700 GMT). . . [251 ] When do you think we will land on Mars? When do you think we will ive on Mras?

Eric&Ryan/Spring Harbor: . . . . Wed, Nov 20, 8:58AM PDT (-0700 GMT). . . [252 ] Is there a possibility of you being the first person to land on Mars?

Andrew/Spring: . . . . Wed, Nov 20, 8:58AM PDT (-0700 GMT). . . [253 ] When do you think people will colonize Mars?

RACHAEL/SRINGHABOR: . . . . Wed, Nov 20, 8:58AM PDT (-0700 GMT). . . [254 ] if you had the chance would you live on mars

BTES, Barre Town, VT: . . . . Wed, Nov 20, 8:58AM PDT (-0700 GMT). . . [255 ] HELLO?????????

Morris: . . . . Wed, Nov 20, 8:59AM PDT (-0700 GMT). . . [256 ] Can you PLEASE answer this question (asked for the third time): are any of the compunds found in the meteor existant on earth??

Joey/Spring: . . . . Wed, Nov 20, 8:59AM PDT (-0700 GMT). . . [257 ] Sorry live and Mars.

sandy: . . . . Wed, Nov 20, 8:59AM PDT (-0700 GMT). . . [258 ] are any of you cool

Sandy/Moderator: . . . . Wed, Nov 20, 8:59AM PDT (-0700 GMT). . . [259 ] Joey: We will land on Mars on July 4, 1997.

David/SpringHarbor: . . . . Wed, Nov 20, 8:59AM PDT (-0700 GMT). . . [260 ] How do you explain the "face" on mars?

sandy: . . . . Wed, Nov 20, 9:00AM PDT (-0700 GMT). . . [261 ] are you smart

Joey/Spring: . . . . Wed, Nov 20, 9:00AM PDT (-0700 GMT). . . [262 ] No when will a human land on Mars?

kurt/ Dodgeville Middle: . . . . Wed, Nov 20, 9:01AM PDT (-0700 GMT). . . [263 ] IF WE BUILD A BIOSphere someday on mars, what would be the most difficult factor to control in order to keep plants alive

sandy: . . . . Wed, Nov 20, 9:01AM PDT (-0700 GMT). . . [264 ] are any of you married

: . . . . Wed, Nov 20, 9:01AM PDT (-0700 GMT). . . [265 ] are you smart sandy

kurt/ Dodgeville Middle: . . . . Wed, Nov 20, 9:01AM PDT (-0700 GMT). . . [263 ] IF WE BUILD A BIOSphere someday on mars, what would be the most difficult factor to control in order to keep plants alive

sandy: . . . . Wed, Nov 20, 9:01AM PDT (-0700 GMT). . . [264 ] are any of you married

: . . . . Wed, Nov 20, 9:01AM PDT (-0700 GMT). . . [265 ] are you smart sandy

: . . . . Wed, Nov 20, 9:02AM PDT (-0700 GMT). . . [272 ] Depends Are you?

BTES, Barre Town, VT: . . . . Wed, Nov 20, 9:02AM PDT (-0700 GMT). . . [273 ] We are leaving. Bye.

Jon/Spring: . . . . Wed, Nov 20, 9:02AM PDT (-0700 GMT). . . [274 ] Are you married Sandy

Andrea/ChatHost: . . . . Wed, Nov 20, 9:03AM PDT (-0700 GMT). . . [275 ] Sorry - Sandy too late.

: . . . . Wed, Nov 20, 9:03AM PDT (-0700 GMT). . . [276 ] sandy aswer us

John Bayne: . . . . Wed, Nov 20, 9:03AM PDT (-0700 GMT). . . [277 ] Jack, I've heard that neither the Global Surveyor or Pathfinder have been sterilized. If life still exists under the surface of Mars, what are the chances of the satellites affecting the organisms?

: . . . . Wed, Nov 20, 9:04AM PDT (-0700 GMT). . . [278 ] Sandy, to late!!!

: . . . . Wed, Nov 20, 9:04AM PDT (-0700 GMT). . . [279 ] hi

David/SpringHarbor: . . . . Wed, Nov 20, 9:04AM PDT (-0700 GMT). . . [280 ] Sorry about that image.

......: . . . . Wed, Nov 20, 9:04AM PDT (-0700 GMT). . . [281 ] hi

sandy: . . . . Wed, Nov 20, 9:05AM PDT (-0700 GMT). . . [282 ] hi every body

Sandy/Moderator: . . . . Wed, Nov 20, 9:05AM PDT (-0700 GMT). . . [283 ] BTES: We never did see your questions! I sent you several messages asking you to resend them but we never saw them. You can get questions abouot Mars answered via email: go to button for further information.

Andrea/ChatHost: . . . . Wed, Nov 20, 9:05AM PDT (-0700 GMT). . . [284 ] Let's stay focused on the topic.

: . . . . Wed, Nov 20, 9:05AM PDT (-0700 GMT). . . [285 ] HI is it fune doing what you do

Sandy/Moderator: . . . . Wed, Nov 20, 9:06AM PDT (-0700 GMT). . . [286 ] David: Ok. Jack will get to your question about the face. He is working on answering all of the remaining unanswered questions right now...

Joffrey/France: . . . . Wed, Nov 20, 9:06AM PDT (-0700 GMT). . . [287 ] Thank you guys 'was very cool. When will Jack do it again

: . . . . Wed, Nov 20, 9:07AM PDT (-0700 GMT). . . [288 ] yo hi foo

Jack/NASA: . . . . Wed, Nov 20, 9:07AM PDT (-0700 GMT). . . [289 ] Hi Joey and Spring, When will we land on Mars and will we ever live there? We will certainly be landing on Mars soon and in fact the next landed mission is called Pathfinder and will be launched next month. Pathfinder is scheduled to set down on the surface of Mars on July 4th next year! As far as humans on Mars, the earliest missions being seriously discussed are 15-20 years from now. Whether we actually send humans will depend on what we find out with the whole suite of robotic mission that we will send in the next 10 years. But it will also depend on how well we do in solving basic technology problems to get humans to Mars and back safely, and in keeping up on the advances in space medicine to ensure the health of astronauts during long space flights. Finally, planetary protection issues will be of great importance because it so hard to decontaminate a human being!

George: . . . . Wed, Nov 20, 9:07AM PDT (-0700 GMT). . . [290 ] Hi I'm Mr. Bobby Smith

Sandy/Moderator: . . . . Wed, Nov 20, 9:08AM PDT (-0700 GMT). . . [291 ] Joffrey/France: Thanks so much for joining us today. We're not sure when we can schedule Jack again; he's a pretty busy guy, but we'll work on it. "Live From Mars" is a year-long project so we will continue to have weekly chats. There won't be one next week due to Thanksgiving holiday, but we will resume the first week of December.

Angelica/ Stillwater: . . . . Wed, Nov 20, 9:08AM PDT (-0700 GMT). . . [292 ] Hi from Stillwater MN.

George: . . . . Wed, Nov 20, 9:08AM PDT (-0700 GMT). . . [293 ] Sorrry that was my other personality

: . . . . Wed, Nov 20, 9:08AM PDT (-0700 GMT). . . [294 ] chirs h. stillwater minn hi

sandy: . . . . Wed, Nov 20, 9:09AM PDT (-0700 GMT). . . [295 ] :-)

PAM/Montrose: . . . . Wed, Nov 20, 9:09AM PDT (-0700 GMT). . . [296 ] Thank you for trying your best!

George: . . . . Wed, Nov 20, 9:09AM PDT (-0700 GMT). . . [297 ] Is any body there? SHUTUP BOBBY!!!

Sandy/Moderator: . . . . Wed, Nov 20, 9:10AM PDT (-0700 GMT). . . [298 ] Hi Angelica and Chris H in Stillwater: Our chat for today is over, however Jack Farmer is still busy answering the questions that he wasn't able to during the 1-hr. chat. He can't answer any new questions, but stay tuned and you can see answers to previously asked questions.

sandy: . . . . Wed, Nov 20, 9:11AM PDT (-0700 GMT). . . [299 ] :-) :-( Hi i am from stillwater florlda

Chris/ Dodgeville Middle: . . . . Wed, Nov 20, 9:11AM PDT (-0700 GMT). . . [300 ] what is your current prodject?

George: . . . . Wed, Nov 20, 9:11AM PDT (-0700 GMT). . . [301 ] Hi Angelica, how are.. hhey I want controll George

Sandy/Moderator: . . . . Wed, Nov 20, 9:11AM PDT (-0700 GMT). . . [302 ] George: This is a Mars WebChat for kids in kindergarten through highschool. Please stop sending your messages.

sandy: . . . . Wed, Nov 20, 9:11AM PDT (-0700 GMT). . . [303 ] bobby shut up..............

: . . . . Wed, Nov 20, 9:11AM PDT (-0700 GMT). . . [304 ] Stillwateer Jr. High is the best

Jack/NASA: . . . . Wed, Nov 20, 9:11AM PDT (-0700 GMT). . . [305 ] Hi John: About sterilizing the Pathfinder lander: Yes there are guidelines that were developed during the Viking missions 20 years ago that are being updated and followed. It is impossible to completely remove all microbes from a spacecraft, but we do strive to attain a minimal bioload of organisms. This is regarded as most important for missions carrying life detection experiments. We don't want to go to Mars looking for life and detect ourselves. As far as altering a Martian biosphere, the risk is considered minimal because surface conditions there are so impossible for Earth organisms. If we were to someday drill below the surface to a zone of liquid water, then we will need to worry. But that will be a long time coming and probably not before human missions.

George: . . . . Wed, Nov 20, 9:12AM PDT (-0700 GMT). . . [306 ] Sorry....bye

Sandy/Moderator: . . . . Wed, Nov 20, 9:13AM PDT (-0700 GMT). . . [308 ] Hi Sandy in Stillwater, Florida. Join us for our next webchat the first week of December. Jack is not taking anymore questions as he was inundated. You can still participate by watching.

Angelica/ Stillwater: . . . . Wed, Nov 20, 9:13AM PDT (-0700 GMT). . . [309 ] Go away George

Sandy/Moderator: . . . . Wed, Nov 20, 9:14AM PDT (-0700 GMT). . . [311 ] Jack has to get back to his real work now. Thank you very much for your time Jack. Your job sounds so interesting!

PAM/Montrose: . . . . Wed, Nov 20, 9:15AM PDT (-0700 GMT). . . [313 ] Thank you we will read all the answer later and print them we have to go by JACK, SANDY, AND ANDERA BY MANDIE STRATTON AND PAM ROCHA

Chris/ Do: . . . . Wed, Nov 20, 9:15AM PDT (-0700 GMT). . . [314 ] If given the

Sandy/Moderator: . . . . Wed, Nov 20, 9:15AM PDT (-0700 GMT). . . [315 ] The correct URL for the Live From Mars project is: button

John Bayne: . . . . Wed, Nov 20, 9:16AM PDT (-0700 GMT). . . [316 ] Thanks Jack, this chat has been fascinating!

Sandy/Moderator: . . . . Wed, Nov 20, 9:16AM PDT (-0700 GMT). . . [317 ] Jack just found a couple of questions that he didn't answer, so he will spend the next couple of minutes with us...

Shasta In Redding, CA: . . . . Wed, Nov 20, 9:17AM PDT (-0700 GMT). . . [318 ] Sandy...will he be able to answer our questions from before?

Sandy/Moderator: . . . . Wed, Nov 20, 9:17AM PDT (-0700 GMT). . . [319 ] Bye John. Join us again the first week of December for the next web chat.

Sandy/Moderator: . . . . Wed, Nov 20, 9:18AM PDT (-0700 GMT). . . [320 ] Shasta: Please resend me your questions and I will make sure they get answered!

Shasta In Redding, CA: . . . . Wed, Nov 20, 9:21AM PDT (-0700 GMT). . . [323 ] Question 1: What would happen if the mars pathfinder were covered with dust from a dust storm and covered the solar panels? So that not sunlight could power the rover. What WOULD happen? Question 2: How do they know that the evidence of life on the Mars meteorite was from mars and not from organisms here on the earth?

Sandy/Moderator: . . . . Wed, Nov 20, 9:23AM PDT (-0700 GMT). . . [324 ] Thanks Shasta: Jack will indeed answer these. He's got 6 questions left to answer and he will then answer your two. Sorry for the delay and thanks for being patient :-)

Jack/NASA: . . . . Wed, Nov 20, 9:25AM PDT (-0700 GMT). . . [325 ] Dear Morris, Sorry for the delayed response. Things were scrolling by pretty fast. By componds in the meteorite, I assume you mean the Martian meteorite, ALH 84001, the one that has caused all the interest of late. The organic compounds reported so far in that meteorite are called polycyclic aromatic hydrocarbons. These are very common compounds on Earth and can be formed in a variety of ways. Many PAH's are formed by combustion and common in auto exhaust for example. Other PAHs are formed during the breakdown of organic matter and are common in petroleum. Unfortunately, we can't really tell the origin of the PAHs in ALH84001, and they could well be inorganic. The other organic compounds in ALH84001 have not yet been analyzed and may give more definitive results about the life question. That work is going on right now and we should know within the next year what else is there and how it compares to the Earth.

Shasta In Redding, CA: . . . . Wed, Nov 20, 9:25AM PDT (-0700 GMT). . . [326 ] Thanks for lwetting me re-ask them

Sandy/Moderator: . . . . Wed, Nov 20, 9:29AM PDT (-0700 GMT). . . [327 ] Shasta: You're welcome! Stay tuned if you can. Otherwise this chat will be archived on the same page that you went to, to do this chat.

Jack/NASA: . . . . Wed, Nov 20, 9:33AM PDT (-0700 GMT). . . [328 ] Hi David: About the so-called Face on Mars. I have studied the region of Mars called Cydonia where the face is located, and it is just one of hundreds of mesa-like forms that have an amazing array of shapes that resemble things like animals, faces, you name it. The way I see it, it is like sitting outside and watching clouds form. Have you ever done that. You can convince yourself you see a whole host of things after a while. I think the face on Mars is interesting only in the sense that it reveals how the human mind and perceptions is always looking for patterns and making comparisons. If we are to accept the face on Mars as the result of an ancient civilization of builders, we will also have to account for lots of other weird-shaped mts there, some looking like dogs and elephants, and one that even looks like Elvis. Point is, it is much more likely and reasonable the face is just another landform scuplted by landslides and glacies, and not the hands of intellegent beings.

Jack/NASA: . . . . Wed, Nov 20, 9:37AM PDT (-0700 GMT). . . [329 ] Hi Kurt: About a Biosphere2 on Mars, probably the most important concern in keeping plants alive would be to make sure there is plenty of water. Mars has a CO2-rich atmosphere and we will have that important ingredient in abundance. It ius water tha may well pose the largest problem. At NASA Ames we have a number of projects going to perfect these kinds of biosphere systems complete with recycling of water, wastes, nutrients and gases like oxygen and CO2. The only other requirement will be soil (the Martian soils is likely to be to full of oxidants to support plant growth) and energy to provide life. The main source of energy will likely be solar based on current technologies and concerns over the safety of radioactive energy sources.

Jack/NASA: . . . . Wed, Nov 20, 9:40AM PDT (-0700 GMT). . . [330 ] Hi Joey: Humans are presently slated to go to Mars in the next 15-20 years. But because of the issues about astronaut safety and health, we have lots of technology development ahead before we can go there and return safely. There is also the important issue of planetary protection and how to properly quarantine astronauts when they return to Earth. These are all costly issues that must be solved, and the research is just beginning!

Jack/NASA: . . . . Wed, Nov 20, 9:46AM PDT (-0700 GMT). . . [331 ] Dear David: About the weight of a robotic rover on Mars, there are all size classes of rovers being designed and tested at JPL and elsewhere within NASA. There are microrovers like Sojourner that will go to Mars next month on Mars Pathfinder. That is a small sover that on Earth weighs about 10 kg. On Mars things weigh about a third less. But there are also much larger rovers like the Russian built Marsokhod rover which we have been testing the past few years which is a macrorover that weighs much more. Then we also are designing nanorovers that only weigh a few kilograms. All of these will be options at different points in Mars exploration, and will be used for different types of missions having different mobility and payload requirements.

Jack/NASA: . . . . Wed, Nov 20, 9:50AM PDT (-0700 GMT). . . [332 ] Hi Amanda! The Earth and Mars are both vulnerable to the effects of large impacts, and we really don't know what all those effects might be. But we do have scientists here at Ames who worry about such issues, and they have models that suggest impacts of objects several hundred kms in diameter might well extinguish much of the higher life forms on the surface of the planet and down to a certain depth in the oceans. It may actually be quite hard to extinguish subsurface microbial life by impact, and in that respect, both the Earth and Mars would be likely to hang onto at least the microbial part of their biospheres (assuming Mars has one of course!) during giant impacts.

Jack/NASA: . . . . Wed, Nov 20, 9:51AM PDT (-0700 GMT). . . [333 ] Question 285: Is it fun doing my job? Yes! It is a real blast!

Jack/NASA: . . . . Wed, Nov 20, 9:59AM PDT (-0700 GMT). . . [334 ] Hi Shasta! The scenario you suggest could be a problem, but not a terminal one. If Mars were in a dust storm when the lander put down, it would likely not begin its work until things cleared up. This happened during the Vining missions periodically, and the work slowed doen or stopped during the peak storms. The solar panels are designed so they can be kept free of dust, so it should not be a problem in the long run. Second question about the ALH84001 meteorite. This is a good question. David McKay and his colleagues from Johnson Space Center in Houston firtst presented their results for the meteorite two years ago at a conference and they were strongly challenged by other scientists to prove that the organic molecules they were seeing were actually primary to the rock and not Earth-based contamintion. This was a challenge that they met very well using very high spatial resolution methods that could localize the organics within certain minerals in the meteorite that we believe formed on Mars. So, by showing the organics were inside the carbonate minerals they were able to convince everyone that the organics were not due to contamination. In addition, they showed that the organics actually increased in abundance as they moved in toward the interior of the rock, just the opposite of what you would expect if they were contaminants!

Sandy/Moderator: . . . . Wed, Nov 20, 10:08AM PDT (-0700 GMT). . . [335 ] Jack has a question or two left to answer and then that's it for today's "Live From Mars" WebChat. Please join us again the first week in December for LFM WebChat #5. The exact date to be posted soon. Thanks again to all of you who participated today! Your questions were some of the best yet!

Jack/NASA: . . . . Wed, Nov 20, 10:10AM PDT (-0700 GMT). . . [336 ] Dear Kurt, Just one correction to my answer (329). When I said: the Martian soils are likely to be to full of oxidants to support plant growth), I meant to say: the Martian soils are full of oxidants (peroxides) that are harmful to plant growth. Sorry, but is hard to proof read everything I have written in such a small window. Alss, my apologies to evryone for the many typos. Just proves I should have paid more attention in typing class!

Jack/NASA: . . . . Wed, Nov 20, 10:12AM PDT (-0700 GMT). . . [337 ] Well, it has been fun and I look forward to another Web Chat very soon. Thanks again for all the great questions! Hope I didnt miss anyone! I'll try and practice my typing between now and next time! Adios! JACK

Andrea/ChatHost: . . . . Wed, Nov 20, 10:12AM PDT (-0700 GMT). . . [338 ] Great Chat Jack! Thanks for your time.