Sandy/NASA Chat Host: . . . . Wed, Apr 16, 8:38AM PDT (-0700 GMT) Hello! Welcome to another "LIVE FROM MARS" WebChat. Our guest today is Geoff Briggs, the scientific director of the Center for Mars Exploration at NASA's Ames Research Center at Moffett Field, CA.

Sandy/NASA Chat Host: . . . . Wed, Apr 16, 9:09AM PDT (-0700 GMT) Good Morning Geoff!

Geoff at CMEX: . . . . Wed, Apr 16, 9:11AM PDT (-0700 GMT) Good morning! I'm involved in planning future Mars missions. What would you like to know?

Bruce: . . . . Wed, Apr 16, 9:02AM PDT (-0700 GMT). I read about pathfinder landing on Mars soon. Are you involved in that? Will you be looking at the data as it comes back?

Bruce: . . . . Wed, Apr 16, 9:03AM PDT (-0700 GMT) Oh yeah, I forgot. Thanks for coming here. I'm excited to learn about Mars for the next 20 minutes...

Geoff at CMEX: . . . . Wed, Apr 16, 9:12AM PDT (-0700 GMT) Bruce: I'm not directly involved in Pathfinder but colleagues here are and I hope to be at the Jet Propulsion Laboratory in Pasadena, CA on July 4th, when Pathfinder lands on Mars.

Shannon/7th grade: . . . . Wed, Apr 16, 9:11AM PDT (-0700 GMT) Can you tell us a bit about the Center for Mars Exploration... what is it and who works there?

Geoff at CMEX: . . . . Wed, Apr 16, 9:13AM PDT (-0700 GMT) Shannon: CMEX helps coordinate Mars science, mission planning and technology development at NASA Ames -- we specialize in exobiology, aero-entry vehicles and surface rover control technology.

Shannon/5th grade: . . . . Wed, Apr 16, 9:14AM PDT (-0700 GMT) Thanks for your answer Geoff! Can you tell me what exobiology is? I haven't heard that term.

Geoff at CMEX: . . . . Wed, Apr 16, 9:20AM PDT (-0700 GMT) Shannon: Exobiology is the study of how life may have evolved elsewhere in the universe. Mars and Europa in our own solar system are the most likely places to look first. And now we are discovering other solar sytems.

Bill/Maine: . . . . Wed, Apr 16, 9:12AM PDT (-0700 GMT) As the "scientific director", what exactly is your role?

Megan/Eberhartd HS: . . . . Wed, Apr 16, 9:13AM PDT (-0700 GMT) If you had the opportunity to go to Mars, would you?

Geoff at CMEX: . . . . Wed, Apr 16, 9:16AM PDT (-0700 GMT) Bill/Megan: "Scientific Director" is just a convenient name for the head of CMEX, reflecting the fact that I am a scientist rather than an engineer. The first human Mars expedition will likely be more than ten years from now and I think I am a little too old to go. The question is "what about you -- are you waiting to get trained and go?"

Bruce: . . . . Wed, Apr 16, 9:14AM PDT (-0700 GMT) When the pictures come down on July 4, is there anythimg scienctists will be looking for in the video. Or can you only tell what's exciting by looking closely at the data (numbers).

Geoff at CMEX: . . . . Wed, Apr 16, 9:18AM PDT (-0700 GMT) Bruce: The data from Pathfinder will be converted into panoramic images immediately and, since there are two camers -- into stereo for viewing by the latest stereo TV and headmounted immersion devices. It will be our first such experience and it promises to be very exciting. We hope the landing site will be different from the Viking sites in ways we can't necessarily anticipate.

Bruce: . . . . Wed, Apr 16, 9:17AM PDT (-0700 GMT) In planning future missions, what is the earliest date now for a sample return mission? There was talk of moving it earlier if more money was dedicated. Is that happening?

Geoff at CMEX: . . . . Wed, Apr 16, 9:22AM PDT (-0700 GMT) Bruce: NASA is making serious plans to launch a sample return mission in 2005 to return here in 2007. The spacecraft will bring back samples collected by spacecraft to be launched in 2001 and 2003 (a choice will have to made betweebn the two as to which samples come back first.)

Joe/Harding MS: . . . . Wed, Apr 16, 9:17AM PDT (-0700 GMT) What exactly are NASA's plans for sending humans to Mars? When, how many people would go on the first voyage?

Geoff at CMEX: . . . . Wed, Apr 16, 9:25AM PDT (-0700 GMT) Joe: We hope that the upcoming robotic missions will have provided enough information and technology demonstrations that we will be ready in about 2004 to seek a commitment to a fitst human mission in 2011 The precursor cargo flights would launch in 2009. We think that a crew of five would have all the needed skills but that six individuals would provide a margin for safety.

Marianne/SF: . . . . Wed, Apr 16, 9:23AM PDT (-0700 GMT) But what about humans to Mars?! Is the first human trip to Mars tied to the success of the Space Station?

Geoff at CMEX: . . . . Wed, Apr 16, 9:27AM PDT (-0700 GMT) Marianne: The Space Station will allow us to demonstrate long duration life support systems and other technology that is reliable enough to support a mission lasting about three years. Also, we can demonstrate new information systems (computer) technologies to make the human Mars mission much more affordable than it would be otherwise.

Tom/8th gr/Morgantown: . . . . Wed, Apr 16, 9:24AM PDT (-0700 GMT) How did your background in Physics help you get where you are today?

Geoff at CMEX: . . . . Wed, Apr 16, 9:29AM PDT (-0700 GMT) Tom: Physics covers a lot of fundamental science and is good training for many careers -- I think it helped me quite a bit. All the sciences help you to think logically and all are valuable backgrounds for people interested in space exploration.

Susan/Emeryville: . . . . Wed, Apr 16, 9:25AM PDT (-0700 GMT) In your bio I can see that you've been involved in a lot of different planetary missions in your career. Do you have a favourite mission or planet?

Geoff at CMEX: . . . . Wed, Apr 16, 9:34AM PDT (-0700 GMT) Susan: Mars is my favorite planet because it is so diverse and, still, mysterious -- lots of big questions about how it evolved and whether we may find life there. My favorite mission was Mariner 9 -- the first Mars orbiter. I was on the imaging team and we had to wait months for a dust storm to clear before we could see the surface. It was well worth the wait! Terrifically exciting!

George/Allanstown, PA: . . . . Wed, Apr 16, 9:27AM PDT (-0700 GMT) Where do you think the first humans to go to Mars will land? Near the poles where I heard there might be water?

Geoff at CMEX: . . . . Wed, Apr 16, 9:31AM PDT (-0700 GMT) George: The polar regions are very interesting and may be a place where we will find organic materials preserved in the ice at depth. The 1998 lander will be going to the south polar area. However, the poles may not be good for human missions -- they are in permanent darkness for many months. But they do have frozen water.

Danelle/San Diego: . . . . Wed, Apr 16, 9:30AM PDT (-0700 GMT) Can you describe the surface of Mars for me? My teacher says that the surface of Earth is 90 percent covered with water. What is most of the surface of Mars liike?

Geoff at CMEX: . . . . Wed, Apr 16, 9:38AM PDT (-0700 GMT) Danelle: The Earth's surface is covered by water over about 2/3 of the area. The martian surface has much less area than Earth but there are no oceans so we see an surface about the area of our continents. Very diverse -- ancient cratered terrain with giant basins, volcanic plains, huge shield volcanoes, a canyon that would spread from California to Virginia, valley networks that resemble ancient river networks, extraordinary vast floods, sand dunes, polar caps ...

Danelle/San Diego: . . . . Wed, Apr 16, 9:42AM PDT (-0700 GMT) That sounds totally cool! It would be fun to ride all over Mars in my ATV! Do you think astroaugnts will do that when they get to Mars?

Michael/Mich.Polytech: . . . . Wed, Apr 16, 9:32AM PDT (-0700 GMT) Does NASA plan to do any archaological diggings when they get to Mars? I heard there might be fossils near the very old river beds that were there a long time ago.

Geoff at CMEX: . . . . Wed, Apr 16, 9:41AM PDT (-0700 GMT) Michael: NASA's will be sending a lander in 2001 that will carry a rover quite a bit bigger than Pathfinder's. It will rake up rock samples and probably drill pieces out of boulders -- we will get to carry out the archeology when the samples come back to Earth -- in just ten years from now. In the meanwhile we hope to study more martian rocks from Antarctica.

George/AllanstownPA: . . . . Wed, Apr 16, 9:35AM PDT (-0700 GMT) Geoff, you said the poles are in permanent darkerness for awhile--is this the same with the poles here on Earth? I thought I saw a PBS spewcial where there were scientists living with the penguins at the south pole. Can't the sceintists drill rhough the ice for drinking water?

Susan/Emeryville: . . . . Wed, Apr 16, 9:37AM PDT (-0700 GMT) Geoff/what is the first thing you saw when the dust cleared? What did you hope to see? Where you disappointed?

Geoff at CMEX: . . . . Wed, Apr 16, 9:44AM PDT (-0700 GMT) Susan: The first thing we saw -- even before the dust cleared -- were the tops of the giant volcanoes which reach up 20 km above the mean level of Mars There was a lot of controversy about whether we were seeing volcanic calderas or simply impact craters. The correct answer was provided by Hal Masursky on the imaging team who had no doubt at all. Unfortunately, he died several years ago now and won't be around for the next set of missions.

Ryan;7th;St. Petersburg: . . . . Wed, Apr 16, 9:40AM PDT (-0700 GMT) With the latest news of Europa in the news, are we going there next?

Geoff at CMEX: . . . . Wed, Apr 16, 9:45AM PDT (-0700 GMT) Ryan: Planetary scientists are very eager to go to Europa -- a tough mission to carry out because of the distance to Jupiter and the extreme radiation. I'm not working on that but others at NASA Ames are.

Bruce: . . . . Wed, Apr 16, 9:41AM PDT (-0700 GMT) Hi again, I had to go away for a while but I got to come back. So about the sample return. Are you saying that one spacecraft will go first and gather the rocks, and then another will go and collect those rocks and return?

Geoff at CMEX: . . . . Wed, Apr 16, 9:46AM PDT (-0700 GMT) Bruce: You are exactly right about the sample return plans.

Bruce: . . . . Wed, Apr 16, 9:43AM PDT (-0700 GMT) Also, about a sample return. People talked about making rocket fuel on Mars for the return mission. Is that seriously being considered or will we bring all of the fuel we need?

Geoff at CMEX: . . . . Wed, Apr 16, 9:50AM PDT (-0700 GMT) Bruce: For the first sample return mission there is a debater about whether to take all the fuel to Mars for the return journey or make it on Mars (we would have to take some hydrogen along to make methane fuel to burn with oxygen extracted from the CO2 atmosphere). For human missions we will HAVE to make our prpellants on Mars to make the mission affordable. That will require taking along a powerful electrical energy supply -- a small nuclear reactor.

Michael/Mich.Polytech: . . . . Wed, Apr 16, 9:44AM PDT (-0700 GMT) You said something about studying Martian meteors in Antartica! What proof do you have they are REALLY! from Mars???

Geoff at CMEX: . . . . Wed, Apr 16, 9:47AM PDT (-0700 GMT) Danelle: What is an ATV?

Danelle/San Diego: . . . . Wed, Apr 16, 9:48AM PDT (-0700 GMT) Oh, that's short for all terrain veicle! It has 3 big wheels and I ride it in the Mojave Dessert with my dad and brothers. We like to ride over the sandunmes.

Geoff at CMEX: . . . . Wed, Apr 16, 9:52AM PDT (-0700 GMT) Danelle: The astronauts will certainly have an ATV -- probably not three wheeled but who knows? They will also need a large pressurized rover so that they ccan go out on field trips lasting for up to a couple of weeks. With an ATV trips will probably only last for a matter of hours because the astronauts will be limited by their air supply.

Sandy/NASA Chat Host: . . . . Wed, Apr 16, 9:49AM PDT (-0700 GMT) EVERYONE: WE WILL TAKE QUESTIONS FOR ANOTHER 5 MINUTES AND THEN GEOFF HAS TO GO BACK TO WORK!

Bruce: . . . . Wed, Apr 16, 9:50AM PDT (-0700 GMT) And do we yet know where the sample will be gathered from? Since you are in planning future missions, do you get to make that decision? If you haven't made the decision yet, when will you make it. And will the results from pathfinder help you to decide where to gather rocks from?

Geoff at CMEX: . . . . Wed, Apr 16, 9:56AM PDT (-0700 GMT) Bruce: The plan is to go to a highland area where there is evidence of water accumulation -- e.g. an ancient lake -- in the past. In another weeks time an announcement will be made by NASA asking for scientists to propose rover experiments and say where they want to go. The actual decision will be made a couple of years from now when we have much more data -- from the upcoming orbiters and landers -- including much higher resolution imaging data and information about surface minerals. Unfortunately, I won't be the one to decide but I hope to be involved.

Sarah: . . . . Wed, Apr 16, 9:50AM PDT (-0700 GMT) I wonder what it was like for you when you started to recieve information from Pioneer...

Geoff at CMEX: . . . . Wed, Apr 16, 10:00AM PDT (-0700 GMT) Sarah: I was not a member of any of the Pioneer teams but I am sure that they felt elated when the first data came back from Venus and Jupiter and Saturn -- it's a uniquely satisfying feeling to be the first one to see what another planet looks like.

Danelle/San Diego: . . . . Wed, Apr 16, 9:55AM PDT (-0700 GMT) Ok Geoff, thanks for your great answers! I have to go back to class now bye.

Michael/Mich.Polytech:: . . . . Wed, Apr 16, 9:56AM PDT (-0700 GMT) I got to go too but please still answer my question about mnars meteors. I'll look for answner tonight when I get home. Thaks!

Geoff at CMEX: . . . . Wed, Apr 16, 9:58AM PDT (-0700 GMT) Michael: You asked how we know that some meteorites found in Antarctica come from Mars. The answer is that it is an inferrence based on the great similarity in the gases that the meteorite contains and those which the Viking landers baked out of the soil of Mars 20 years ago. It seems pretty firm.

Bruce: . . . . Wed, Apr 16, 10:00AM PDT (-0700 GMT) How does NASA choose who gets to make such an importnat decision. Iknow the time is running out, so that will be my last questions. Thanks you so much Mr. Briggs. I want to learn a lot more about Mars, and I am excited about July 4 because of Pathfinder.

Geoff at CMEX: . . . . Wed, Apr 16, 10:02AM PDT (-0700 GMT) Bruce: Big decisions are usually made after much discussion among many scientists and enginers who take all sorts of considerations into account. Usually a consensus emerges. If not, then the Project Manager gets to decide -- that why he makes his salary!

Sarah: . . . . Wed, Apr 16, 10:02AM PDT (-0700 GMT) Woops I see that you were a NASA Headquarters at that time. Well what advice do you have for a person interested in working for NASA when they grow up?

Geoff at CMEX: . . . . Wed, Apr 16, 10:06AM PDT (-0700 GMT) Sarah: NASA employs all sorts of people besides scientists and engineers (though most folks have technical training). The key is to get a good education and pay attention to what is going on in the spac arena and the world at large so that you can bring an open and educated mind to bear. Staying interested and enthusiastic is the key -- true for most anything in life.

Sandy/NASA Chat Host: . . . . Wed, Apr 16, 10:07AM PDT (-0700 GMT) THANK YOU very much to everyone for sending your questions today! And a special thank you to Geoff Briggs for taking the time to join us! Your answers were very informative! Hope you can join us again in the future!

Geoff at CMEX: . . . . Wed, Apr 16, 10:07AM PDT (-0700 GMT) Goodbye for now! I look forward to chatting with you again sometime in the future.