Sandy/NASA Chat Host: . . . . Tue, Mar 25, 9:09AM PDT (-0700 GMT). . . WELCOME Everyone! Our Mars expert for today is planetary scientist Ted Roush from NASA's Ames Research Center, near San Francisco, California.

Ted studies the composition of solid surfaces throughout the solar system. He is particularly interested in the minerals and rocks found on the surfaces of rocky bodies and the different kinds of ices found on the surfaces of icy bodies.

Ted's work includes telescopic and spacecraft observations, laboratory work and computer calculations. He use telescopes located on Earth and on spacecraft to measure the sunlight that is reflected from the surfaces of objects in the solar system. Welcome Ted! We're really glad you could join us today.

Ted/NASA Ames: . . . . Tue, Mar 25, 9:10AM PDT Hello Everyone, I am now on-line and we will begin to answer your questions.

Dzsudzsi,Zrinyi(Middle),Hungary: . . . . Tue, Mar 25, 9:09AM PDT (- 0700 GMT) Ted : Why is the Mars red?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:14AM PDT (-0700 GMT) Dzfudzsi: Mars is red because it is rusty. The materials on the surface appear to have suffered the same fate as iron-bearing materials on the earth.

Matthew/Berea: . . . . Tue, Mar 25, 9:11AM PDT (-0700 GMT) What is the most interesting formation you have discovered about any planet?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:13AM PDT (-0700 GMT) Matthew: Although we haven't "seen them, some of the ices on the various moons in the outer solar system are quite interesting. These ices are methane, water ice, carbon dioxide ice, carbon monoxide ice and nitrogen ice.

Anna,Zriny(Middle),Hungary: . . . . Tue, Mar 25, 9:14AM PDT (-0700 GMT): What do you think, can the rover find any sign of life??

Ted/NASA Ames: . . . . Tue, Mar 25, 9:16AM PDT (-0700 GMT) Anna: The reported signs of life are microscopic in size. The current rover will probably have a difficult time to find and identify anything on a microscopic scale.

Jan/Canada: . . . . Tue, Mar 25, 9:15AM PDT (-0700 GMT) Do all ice type reflect light in the same way?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:17AM PDT (-0700 GMT) Jan: At visible wavelengths, most ices look pretty similar, they are white. However at infrared wavelengths the various ices will appear quite different.

Matthew/Berea: . . . . Tue, Mar 25, 9:16AM PDT (-0700 GMT) What is your favorite kind of space rocks?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:18AM PDT (-0700 GMT) Matthew: My favorite space rocks are meteorites believed to have come from Mars. Although it would be very interesting to obtain space "rocks" from comets.

Diane/Wesley-Maywood Center: . . . . Tue, Mar 25, 9:17AM PDT (-0700 GMT) Hello, everyone, we are checking in!

Tibor/Zrinyi Middle Hungary: . . . . Tue, Mar 25, 9:17AM PDT (-0700 GMT): Ted: I'm interesting in the APXS very much. Where can I find any information about it in the Internet? (I'm a physics teacher.)

Ted/NASA Ames: . . . . Wed, Apr 9, 9:22AM PDT (-0700 GMT): Tibor: The February 1997 issue of "Journal of Geophysical Research-Planets" is dedicated to the Mars Pathfinder Mission. It contains an article describing each instrument. None of them describe an Internet site, but by taking 10 minutes and surfing about I found http://mpfwww.arc.nasa.gov/mpf/sci_desc.html#APXS

I'll let you decide if it provides enough information for your interests.

Anna,Zrinyi(Middle),Hungary: . . . . Tue, Mar 25, 9:18AM PDT (-0700 GMT): Ted : What do you think,can people live on Mars??

Ted/NASA Ames: . . . . Tue, Mar 25, 9:22AM PDT (-0700 GMT) Anna: People can live on Mars but will require a tremendous amout of life-support equipment. You just can't walk around on the surface because there is very little oxygen in the atmosphere. It would be kind of difficult to breath.

Levente/Zrinyi(middle,Hungary): . . . . Tue, Mar 25, 9:19AM PDT (- 0700 GMT): Hello Ted! What do you think, can the new Mars expeditions answer the question: Does Mars have fluid magma?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:24AM PDT (-0700 GMT) Levente: Perhaps ultimately the missions being discussed for Mars exploration will be able to address liquid magmas on Mars. However the first few missions do not carry any specific instruments designed to measure seismic (marsquake) activity.

Sandy/NASA Chat Host: . . . . Tue, Mar 25, 9:20AM PDT (-0700 GMT) Tibor: Good question! Ted is looking through a magazine right now, trying to find a good answer for you....

Cassie/Berea: . . . . Tue, Mar 25, 9:20AM PDT (-0700 GMT) What kind of rock is Mercury made of?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:26AM PDT (-0700 GMT) Cassie: Good question! Mercury appears to be similar to the moon although it may be less iron-rich. This means that the rocks on Mercury will be kind of like basalts on the earth.

Wesley-Maywood Center: . . . . Tue, Mar 25, 9:21AM PDT (-0700 GMT) What is Mars's two moons made out of?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:28AM PDT (-0700 GMT) Wesley-Maywood: We don't have an exact answer, but they appear to be similar to meteorites found on the earth that are believed to have been formed early in the history of the solar system.

Sandy/NASA Chat Host: . . . . Tue, Mar 25, 9:21AM PDT (-0700 GMT) Tibor: Can't seem to find any information right now...but I will get back to you with email after the chat today!

Wesley-Maywood Center: . . . . Tue, Mar 25, 9:23AM PDT (-0700 GMT) To Ted: Can astronauts and scientist change the atmosphere of Mars? What is your opinion?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:30AM PDT (-0700 GMT) Wesley-Maywood: Astronauts and scientists might be able to change the atmosphere of Mars, but this would take a major effort. Like the Earth, the martian atmosphere would eventually respond to gases released into it but depending upon the other gases would require lots of them.

Cassie/Berea: . . . . Tue, Mar 25, 9:24AM PDT (-0700 GMT) People keep looking for life like us, but maybe they don't need oxygen and water, could this be possible?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:31AM PDT (-0700 GMT) Cassie: Water appears to be essential to life as we understand it. Some organisms on the earth do not require oxygen, but they do require water. Would we be able to recognize life if we didn't know what to look for?

Levente/Zrinyi(middle,Hungary): . . . . Tue, Mar 25, 9:25AM PDT (- 0700 GMT): I read that the vulcano erruptions aren't working anymore - does this mean that Mars is a "cold" planet and the look of the surface is only made by the weather?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:34AM PDT (-0700 GMT) Levente: There have been no volcanic eruptions observed on Mars. There are many volcanoes that appear to be "fresh" or young. Mars is currently a very cold planet. The surface and atmosphere (weather) interact, so what we see is the result of the weathering of the surface.

Tibor/Zrinyi Middle Hungary: . . . . Tue, Mar 25, 9:27AM PDT (-0700) Ted: OK, I'm waiting for your letter. It would be very useful for us. Another easier question (I hope). How can they determine the exact (real) landing site of the Pathfinder (and other landers)? Is the navigation so precise?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:51AM PDT (-0700 ) Tibor: The location on Mars that Pathfinder will land is Ares Vallis (19.5N latitude, 32.8W longitude). The landing error ellipse is 70km by 200 km. The actual landing will involve deployment of airbags and it is anticipated that the lander will bounce several time before coming to a halt.

Matthew/Berea: . . . . Tue, Mar 25, 9:28AM PDT (-0700 GMT) Do you think there is life on Mars, even if it is bacteria?

Wesley-Maywood Center: . . . . Tue, Mar 25, 9:30AM PDT (-0700 GMT) Ted: COULD bacteria live on Mars?

Wesley-Maywood Center: . . . . Tue, Mar 25, 9:30AM PDT (-0700 GMT) Ted: If they change the atmosphere could we live there?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:36AM PDT (-0700 GMT) Wesley-Maywood & Matthew: Bacteria could live on Mars, but only in very special locations. The surface is not hospitable for life, there is no liquid water and it is cold. Thus any bacteria would need to find a location where liquid water was present, such as below the surface or near any hot spring, if they exist.

Daniel, Zrinyi (Middle),Hungary: . . . . Tue, Mar 25, 9:32AM PDT (-0700 GMT): Hello Sandy! Hi Ted! I'm Daniel from Hungary. How thick is the sand on the Mars?

Ted/NASA:. . . . Wed, Apr 9, 9:35AM PDT (-0700 GMT): Daniel: Like the Earth the answer is not a single number. There are regions on Mars where the sand is believed to be very thin or non-existant. There are other areas where the sand is believed to be fairly thick (several km).

Sandy/NASA Chat Host: . . . . Tue, Mar 25, 9:35AM PDT (-0700 GMT): Welcome Daniel in Hungary! We are very happy that you joined us again today!

Cassie /Berea: . . . . Tue, Mar 25, 9:32AM PDT (-0700 GMT) Do you believe that Mars once had life, other than bacteria?

Ted/NASA: . . . . Wed, Apr 9, 9:32AM PDT (-0700 GMT): The presence of life on Mars requires the presence of liquid water. Hence we can ask if liquid water occured on Mars for a long enough time that early life as we know it here on Earth might occur on Mars. If we understand how early planetary atmospheres developed as well as we think, then Mars could have had a much thicker atmosphere than is currently observed. This would mean that liquid water would have probably been stable at the surface, as it was on the Earth. Thus without any direct evidence, we would expect that life could have formed and evolved on Mars. Whether or not it evolved beyond the stage of bacteria or not is a key question, the answer of which currently remains unknown.

Cassie: . . . . Tue, Mar 25, 9:33AM PDT (-0700 GMT) Do you think that there is water on Mars?

Sandy/NASA Chat Host: . . . . Tue, Mar 25, 9:38AM PDT (-0700 GMT) Cassie: There is no liquid water on Mars.

Wesley-Maywood Center: . . . . Tue, Mar 25, 9:34AM PDT (- 0700 GMT): Ted: What is the name of the largest and longest canyon? I need this answer for a comparison chart from school.

Sandy/NASA Chat Host: . . . . Tue, Mar 25, 9:36AM PDT (-0700 GMT) Wesley-Maywood: The largest and longest canyon on Mars is Valles Marineras.

Cassie/ Berea Community: . . . . Tue, Mar 25, 9:35AM PDT (-0700 GMT) Do you ever think humans may live on Mars, or any of it's sattleites?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:38AM PDT (-0700 GMT) Cassie: The technology to support life on Mars currently exists. However, it is expensive, so governments (and hence tax payers) must be willing to commit their resources to such a project.

Wesley-Maywood Center: . . . . Tue, Mar 25, 9:36AM PDT (-0700 GMT) How tall can the sand dunes get?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:40AM PDT (-0700 GMT) Wesley-Maywood: I don't know the specific answer to how tall the sand dunes on mars might possibly get. I do know that there are several extensive dune fields on Mars.

Jan/Montreal: . . . . Tue, Mar 25, 9:37AM PDT (-0700 GMT) Ted: When you say "weathering" is responsible for the surface of Mars, does that imply that water might have been involved in breaking up the rock? And in aiding oxidation of the irons?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:42AM PDT (-0700 GMT) Jan: Weathering on Mars includes water and wind activity on Mars. There are plenty of features on Mars that suggest that water was once more abundant on the surface at some time in Mars' past.

Matthew/Berea: . . . . Tue, Mar 25, 9:38AM PDT (-0700 GMT) In all of your years of studying space what or who made the most impression?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:46AM PDT (-0700 GMT) Matthew: The individual who influenced me the most was the late James Pollack. After I finished my college graduate work, I came to NASA Ames to work with him. He allowed me to pursue my research interests and provided me with moral and scientific support.

Wesley-Maywood Center: . . . . Tue, Mar 25, 9:38AM PDT (-0700 GMT) Does anyone know the deminsions for Valles Marineras?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:44AM PDT (-0700 GMT) Wesley-Maywood: You can get a map of Mars (or globe) and measure the dimensions of Valles Marinaris. Some of these maps are available on CDROMs.

Cassie/Berea: . . . . Tue, Mar 25, 9:40AM PDT (-0700 GMT) What is the most interesting kind of rock formation you have seen?

Ted/NASA Ames: . . . . Tue, Mar 25, 9:54AM PDT (-0700 GMT) Cassie: I have many favorite rock formations that occur in different environments. The summit of Mauna Kea in Hawaii is spectacular for illustrating volcanic landscapes. The metamorphic rocks found in the Cascade and Sierra Nevada Mountains are equally fantastic. The sedimentary rocks of the southwest, such as Arizona, Utah and Colorado are quite striking.

Matthew /Berea: . . . . Tue, Mar 25, 9:42AM PDT (-0700 GMT) What is the core of Mars made of?

Ted/NASA: . . . . Wed, Apr 9, 9:42AM PDT (-0700 GMT) There is not direct measurement of the composition of the Martian core. This is not surprising since there are no direct measurments of the Earths core composition. However, based upon the mean density and moment of inertia of Mars a core containing FeS (iron sulfide) rather than pure Fe (iron) is favored.

Matthew /Berea: . . . . Tue, Mar 25, 9:43AM PDT (-0700 GMT) What does Mars look like through a telescope?

Ted/NASA: . . . . Wed, Apr 9, 9:43AM PDT (-0700 GMT): Matthew: It looks red, check it out for yourself!

Matthew /Berea: . . . . Tue, Mar 25, 9:44AM PDT (-0700 GMT) Do you believe that our Solar System was born by the erruption of another Solar System, if so could there have been life in that Solar System?

Ted/NASA: . . . .Wed, Apr 9, 9:44AM PDT (-0700 GMT): Matthew: It is believed that the collapse of gases to form our solar system was caused by shock waves produced by the explosion of a nearby star. These gases may well have contained hydrogen, carbon, nitrogen, and oxygen, the elements necessary for life. These elements may have combined and condensed into solids that were eventually incorporated into the planets of our solar system. However, how much of this original material survived the formation of the solar system is the subject of current research.

Matthew /Berea: . . . . Tue, Mar 25, 9:47AM PDT (-0700 GMT) What is the adverage tempature on Mars during the night?

Ted/NASA. . . . Wed, Apr 9, 9:47AM PDT (-0700 GMT): Matthew: Like on Earth the answer depends upon where you are. Night temperatures in the Earth's polar regions are much colder than near the equator. This is the same on Mars. The nighttime low temperatures on Mars range from about 140 degrees Kelvin (-133 degrees C or -207 degrees F) near the poles to about 180 degrees Kelvin (-93 degrees C or -135 degrees F) near the equator, during summer.

vince/boeing: . . . . Tue, Mar 25, 9:47AM PDT (-0700 GMT) Is there an enviornment on earth that is very similiar to one on Mars? Geologically speaking!

Ted/NASA Ames: . . . . Tue, Mar 25, 9:58AM PDT (-0700 GMT) Vince: There are some environments on Mars that are kind of similar to a couple of locations on the Earth. The underlying difference is the atmospheric pressure. Antarctica is similar in climate to Mars, but is actually a little bit warmer. The volcanoes that form the Hawaiian Islands are similar to the volcanoes on Mars. The Grand Canyon in Arizona is perhaps a smaller scale version of Valles Marinaris.

Daniel, Zrinyi (Middle),Hungary: . . . . Tue, Mar 25, 9:47AM PDT (- 0700): Ted, can you speak German?

Ted/NASA: . . . . Wed, Apr 9, 9:58AM PDT (-0700 GMT): Daniel: I'm afraid that languages are not my specialty. I can speak only a very

Matthew: . . . . Tue, Mar 25, 9:50AM PDT (-0700 GMT) What is the most interesting planet in our Solar system, and the most interesting thing about Mars?

Ted/NASA: . . . . Wed, Apr 9, 9:58AM PDT (-0700 GMT): Matthew: You will get a different answer from each person you ask about what is the most interesting planet in out solar system. To me, objects in the outer solar system, for example Pluto and Neptune's moon Triton, that may perserve materials that formed very early in the formation of the soalr system are very interesting. For me, the most interesting thing about Mars is that at one time liquid water was present at the surface but now liquid water is very rare. What happened to the atmosphere that could support the presence of liquid water?

Levente/Zrinyi(middle,Hungary): . . . . Tue, Mar 25, 9:51AM PDT (- 0700 GMT): The MPF will land in an area where probably a river has flown - What do you think, was there a time period when there could be fluid water on Mars? If yes, what do you think about the ALH meteorit with bacterias?

Ted/NASA: . . . . Wed. Apr 9, 9:51AM PDT (-0700 GMT): Levente/Zrinyi: If we understand how early planetary atmospheres developed as well as we think, then early in Mars' history it could have had a much thicker atmosphere than is currently observed. This would mean that liquid water would have probably been stable at the surface, as it was on the Earth.

I believe that the evidence for bacteria associated with ALH84001 meteorite is far from convincing.

Matthew: . . . . Tue, Mar 25, 9:52AM PDT (-0700 GMT) If you had a chance to live on Mars would you?

Ted/NASA: Wed. Apr 9, 9:51AM PDT (-0700 GMT): Matthew: I'd love to visit Mars on an extended field trip. However, it is more likely that younger people like yourself will have an opportunity to actually live on Mars for long periods of time.

Levente/Zrinyi(middle,Hungary): . . . . Tue, Mar 25, 9:55AM PDT (- 0700 GMT): How can you determin the EXACT coordinates of the MPF after landing on the surface of the Mars?

Ted/NASA: . . . . Wed, Apr 9, 9:52AM PDT (-0700 GMT): Levente/Zrinyi: The lander has a variety of instruments to record motions during the landing. Radio communications with the lander will also help to constrain its location. I suspect that images obtained during subsequent missions (Mars Global Surveyor arrives in September 1997) will also be used to constrain MPF coordinates.

Sandy/NASA Chat Host: . . . . Tue, Mar 25, 9:58AM PDT (-0700 GMT) THANKS TO ALL OF YOU FOR JOINING US TODAY. THERE WERE A LOT OF QUESTIONS THAT WE WEREN'T ABLE TO ANSWER, BUT WE WILL TRY VERY HARD TO GET TO ANSWER THEM IN THE NEXT WEEK OR SO!

Wesley-Maywood Center: . . . . Tue, Mar 25, 9:59AM PDT (- 0700 GMT): Goodbye, From Seattle, Washington, USA

Tibor/Zrinyi Middle Hungary: . . . . Tue, Mar 25, 9:59AM PDT (-0700 GMT): Bye Ted, bye Sandy

vince/boeing: . . . . Tue, Mar 25, 9:59AM PDT (-0700 GMT) Thanks Ted/Sandy for the chat!

Ted/NASA Ames: . . . . Tue, Mar 25, 10:00AM PDT (-0700 GMT) Dear All: It has been fun. I'm sorry but I must go to a meeting. Within the next week I will try to answer some of the questions that I didn't have time to get to.

Daniel,Zrinyi(Middle),Hungary: . . . . Tue, Mar 25, 10:02AM PDT (-0700 GMT): Good bye Sandy and Ted. Have a nice day!<

Levente/Zrinyi(middle,Hungary): . . . . Tue, Mar 25, 10:03AM PDT (- 0700 GMT): I've recieved Sandy's message... So good bye Everyone! Logging out now...Bye

Sandy/NASA Chat Host: . . . . Tue, Mar 25, 10:04AM PDT (-0700 GMT) Goodbye Everyone! It was really good to have all of you joint us this week. See you next week :-)