October 16-20, 2000 NASA QuestForum with Mike Mellon Mars Global Surveyor University of Colorado

[ MikeMellon/MarsGlobalSurveyor - 5 - 13:46:43 ]
RE: [Mark] What will it take to make Mars' atmosphere breathable for humans?
Mark, Mars' atmosphere currently contains about 95% carbon dioxide and trace amounts of oxygen. In addition, the atmospheric pressure at the surface of Mars is about 1/100 of the Earth's atmospheric pressure at its surface. Both of these factors make Mars' atmosphere unsuitable for us to breath. We would need to alter the atmosphere by adding oxygen and rasing the pressure. But we can't breath pure oxygen, nor can we breath a great deal of carbon dioxide. We would need to add some other inert gas, like nitrogen as on Earth. How much oxygen and inert gas will depend on exactly what humans need. Which becomes a biology question.

[ Oran/NASAChatHost - 7 - 06:29:34 ]
We will continue posting questions through Friday, October 20. Be sure you have read Mike's profile at http://quest.nasa.gov/sso/team/mellon.html to prepare your questions.

[ MikeMellon/MarsGlobalSurveyor - 16 - 13:48:55 ]
RE: [Tanya] What do you think the "face" on Mars really is?
Tanya, from images of Mars of the "face" feature, we can see that it is a rocky hill that only resembles a human face under some lighting conditions (the sun relatively low on the horizon). In the geographic region that the face is found there are many rocky hills that formed from water erosion. The face hill is just one of these hills.

[ MikeMellon/MarsGlobalSurveyor - 17 - 14:07:52 ]
RE: [Kyle] I know you are a Mars expert, but I am interested in Jupiter. Would the Great Red Spot pull you in if you got close enough?
Kyle, The great red spot is a very large storm, like a hurricane. If you were in an airplane on Jupiter and flew into the storm, you might experience a bumpy ride. I think that the wind speed in the red spot gets up to about 100 meters per second, that's about 200 miles per hour. You might need a fast airplane.

[ MikeMellon/MarsGlobalSurveyor - 18 - 14:14:32 ]
RE: [Shekar/Ronny] Do you think that there is any kind of life on Mars?
Ronny, I think that there may have been life on Mars in the distant past when things were warmer and wetter. There may even be life today in some niche where there is enough food, warmth, and water to survive. But I don't think that life on Mars would have had much time (or food and energy) to evolve much, and if life existed or still exists, it is probably no more complex than a single cell, like a bacteria or an amoeba.

[ MikeMellon/MarsGlobalSurveyor - 19 - 14:21:35 ]
RE: [LaDerrick/Jamillah] Do you think that there might be underground oceans on Mars?
Jamillah, I think that there is probably a lot of liquid water underground on Mars in aquifers below the permafrost. This is water in the pores of the soil and in cracks in rock, as apposed to open bodies of water like an ocean. The underground water will be deep, several miles down, because the surface of Mars is very cold. Any water near the surface will freeze, ending up as ice. Deeper down geothermal energy will warm the ground and eventually, if you go deep enough, the ice will melt.

[ MikeMellon/MarsGlobalSurveyor - 20 - 14:25:52 ]
RE: [Shelby/Adrain] Have you heard a lot of rumors about mysterious facts and nonfacts about Mars? Do you believe in any of these remarks?
Adrain, I am not sure what mysterious facts and non-facts you are referring to. Can you be more specific?

[ MikeMellon/MarsGlobalSurveyor - 21 - 14:47:58 ]
RE: [Amber] Do you think that the two moons of Mars are captured asteroids?
Amber, I suspect that the two Moons of Mars (Deimos and Phobos) are captured asteroids. While their origin is not definately known, they resemble asteroids in many ways. They are dark, heavily cratered objects and their color is similar to C-type asteroids. However, their orbits are quite circular suggesting that they formed in place. To know for sure we would need to send a space craft to examine their composition and nature to compare with what we know about true asteroids in the solar system.

[ MikeMellon/MarsGlobalSurveyor - 22 - 14:56:10 ]
RE: [Devin/AJ] Our class is sending each person's name to Mars on the Mars 2001 Lander. Have you sent your name in yet?
No I haven't sent my name to Mars yet. Scientists who are directly involved with building space craft instruments get to send their name to Mars. I'm only involved in analyzing data sent back from space craft, and I have not yet been involved in building a space craft. That's OK. I'm young. I expect that I'll more involved in future Mars missions.

[ MikeMellon/MarsGlobalSurveyor - 23 - 15:03:07 ]
RE: [Zac] What is you favorite space movie? Have you seen Mission to Mars?
Zac, no, I have not seen Mission to Mars. I have a number of favorite space movies, including a number of the Star Trek movies, Alien which is also very scary, 2001 Space Odyssey a classic, and of course Star Wars. [ MikeMellon/MarsGlobalSurveyor - 47 - 15:35:41 ]
RE: [Mark] Mike, I know terraforming Mars is possible even though it may be a centuries-long process involving complex technologies we've yet to create. Do scientists such as yourself view terraforming as a goal you're building toward in your current work? Or, does your work contribute to a more short-term goal, such as colonization?
Mark, I view the study of Mars as serving three goals: increasing knowledge of the universe around us for our own curiousity; learning more about Mars to help us understand our Earth; and learning more about Mars for future colonization. I'm not convinced that terraforming is the best goal. We humans have a tendency to want to modify our environment to suit us, rather than working with nature. Mars is a beautiful natural environment. To terraform Mars would be like cutting down a rain forest or paving over a desert. We have to ask ourselves if we are willing to give up the Mars we have today for what we might gain, if we could do it correctly.

[ MikeMellon/MarsGlobalSurveyor - 48 - 15:39:05 ]
RE: [LaceyandLaTeece] I studied the planet Pluto for a school project. I learned that there might be another planet called Planet X. Do you think that there really is another planet beyond Pluto?
There are many objects beyond Pluto that are part of our solar system. Comets are thought to originate from a cloud of comets far away from our sun, but still in orbit around our sun. Objects the size of planets might exist out there, but they remain to be discovered.

[ MikeMellon/MarsGlobalSurveyor - 49 - 15:43:11 ]
RE: [Shay] I know that many planets have been hit by asteroids. What are the chances of one hitting Earth?
Shay, rocky and icy objects are constantly hitting the Earth. The smaller they are the more frequent they hit. The smallest objects burn up in the atmosphere and never make it to the ground. The larger objects, like asteroids are less frequent, hitting the Earth only every million or so years. These are the ones we worry about, but the larger they are the easier they are to see in space and so we can be warned and take some action to avoid the collision.

[ MikeMellon/MarsGlobalSurveyor - 50 - 15:46:21 ]
RE: [Candace] How many years did you work for NASA? What was your most memorable experience?
Candace, I worked for NASA Ames [Research Center] for about 3 years. The work I do now is very similar, just in a different office. But at Ames there is also an airport with lots of planes of all sorts. Getting to watch the aircraft taking off, landing, or just hovering was quite fun.

[ MikeMellon/MarsGlobalSurveyor - 51 - 15:51:36 ]
RE: [Josh] I would like to know when you think there will be a manned mission to Mars? When there is, would you like to be a part of it? If I wanted to be a part of the team, what kind of training would I need to have?
Josh, I think there will be a human mission to Mars sometime this century. But I'm not sure when. We are still novices at space exploration, and we need to take careful small steps first, like the space station, or a lunar station. If you were interested in going to Mars, you should learn more about science. It's probably less important which science, since experts in all areas will be needed. You might also learn some hands on engineering and get lots of exercise.

[ MikeMellon/MarsGlobalSurveyor - 52 - 15:55:44 ]
RE: [Michelle/StCathRiv] I understand that surface dust and weathering of rocks can prevent instruments such as TES from determing the true composition of rocks on Mars. Will any of the 2001 Orbiter instruments be able to detect more of what lies beneath the visible surface of Mars? What instruments are planned for the 2003 rovers?
The Thermal Emission Spectrometer (TES) on the Mars Global Surveyor space craft can actually detect some mineral through a thin dust or weathering rind coating. On the 2001 orbiter, schedule to launch next spring, is a Gamma Ray and Neutron spectrometer which can detect elements in the top meter or so of the surface. It cannot tell us what minerals are there but it can tell us what those minerals are made of. I do not know off hand what instruments are planned to the 2003 landers.

[ MikeMellon/MarsGlobalSurveyor - 53 - 15:58:38 ]
RE: [Michelle/StCathRiv] How often are you truly surprised by discoveries on Mars? When something *new* is detected, does it tend to make big changes in your thinking or do the *new* discoveries back up your theories?
A bit of both. Theories are backed up by new observations and it is gratifying that we were able to figure something out and make a correct prediction. But new discoveries (such as the recently reported water carved gullies) break the existing theories, since we would not have predicted them. It becomes exciting to find a new explanation. How often this happens depends on how often we get new data.

[ MikeMellon/MarsGlobalSurveyor - 54 - 16:02:03 ]
RE: [Michelle/StCathRiv] When you study the data from MGS, specifically what equipment data are you processing? I assume that TES data gives you some of the information you need. What other instruments are important to your specific studies?
I need to take advantage of all the data to develope theories and improve our understanding of Mars. We can't disregard some data because it doesn't fit. Instead we need to alter our theories. To me, in studying permafrost, the most important data are temperatures, elevation, and images. It would also be nice to know what the humidity is in the atmosphere, but we do not yet have an instrument in orbit to make that measurement.

[ MikeMellon/MarsGlobalSurveyor - 55 - 16:06:43 ]
RE: [Michelle/StCathRiv] Scientists from many different locations around NASA and in a variety of universities are studying Mars. How do all of you in the *NASA community* work together? How does a university get selected to be the one responsible for leading a mission? How do Principle Investigators get their projects accepted? Is there a lot of competition between different universities or do you tend to pool your resources?
The scientists tend to work together by discussing ideas at large meetings each year and regular phone calls, email, etc. As for specific projects, each of us proposes (in writing) to NASA or other funding agencies to work on specific projects, usually as small groups or scientists from the same or different Universities. The proposals are reviewed by NASA and the best ones are selected. Yes, there is a good deal of competition.

[ MikeMellon/MarsGlobalSurveyor - 56 - 16:10:43 ]
RE: [Michelle/StCathRiv] As a scientist, do you tend to work alone or as part of a team?
As a scientist I work both on my own and with others, depending on the project. Simple projects I usually work on by myself. On larger projects, such as space craft data analysis, I work with people both at my University and at other institutions. I also end up travelling frequently to meet with collegues. It really depends on how each different person's skills fit together and what experiences are needed to solve a particular problem.

[ MikeMellon/MarsGlobalSurveyor - 57 - 16:16:06 ]
RE: [Michelle/StCathRiv] How long did it take you to get a PhD? It seems that more people than ever have PhDs and they seem to get them at a younger age than in the past. Are higher level degrees becoming more important? After you complete a PhD, do you stop going to school?
I took a total of 11 years of college to get my Ph.D. 5 years for my BS and 6 more for the PhD. I decided I needed this doctorate in order to do the work I wanted to do. I wanted to be able to define my own research projects and choose what problems to work on. Not everyone needs an advanced degree to do science or to study planets. It may be that it appears that more people have Ph.D's because more people have access to higher education to pursue a science career, but I'm just guessing.

[ MikeMellon/MarsGlobalSurveyor - 58 - 16:17:44 ]
RE: [Shelby] What is your most favorite aspect of your job?
Shelby, my favorite part of my job is when I figure our something that no one has figured out before. It gives me a sense of satisfaction that I was able to contribute.

[ MikeMellon/MarsGlobalSurveyor - 59 - 16:27:23 ]
RE: [Michelle/StCathRiv] Do you have any advice for the *reluctant* student who does not take school very seriously? Do you have any advice for the students with learning or other disabilities who find that school is a very tough challenge every day?
I think each person is good at something and that when you're good at something you enjoy it. We each need to find what we are good at and enjoy learning about it. The excitement and motivation that follows from that will spill into other classes or topics that we are maybe not so excited about. Then something you dislike but need to graduate becomes tolerable, maybe [even] a little fun.

[ MikeMellon/MarsGlobalSurveyor - 60 - 16:29:41 ]
RE: [Ronny] How tall is Olympus Mons?
Ronny, The volcano Olympus Mons is about 23 kilometers above the northern planes of Mars.

[ MikeMellon/MarsGlobalSurveyor - 61 - 16:33:21 ]
RE: [David] I am currently attending school and i would like to study the area of Astrophysics, The thing is that i would also like the experince of actually being part of a space flight.Is there any possibility that these two things could be linked up together?
David... definately! Many of the astronauts on the space shuttle missions are also scientists - mission specialists. They have science education backgrounds and work on specific experiments for their flight. Getting a degree in astrophysics is an excellent start towards working in space. But you don't just need a space science degree. Any science degree [such as], geology, biology, chemistry, engineering, and others, will also help get you into space.

[ MikeMellon/MarsGlobalSurveyor - 63 - 16:39:54 ]
RE: [Ashley] If Jupiter was a little bit larger, would it be its own sun and would the moons be considered its planetary system?
Ashley, Yes, Jupiter could have become a sun if it were bigger. The moons around Jupiter would then be a little planetary system. When speaking of individual planetary objects (moons, planets, etc.) I tend to thinkof them all as planets. It seems kinda silly to call the largest moons of Jupiter moons when they are bigger than some planets.

[ MikeMellon/MarsGlobalSurveyor - 64 - 16:42:07 ]
RE: [Jocelyn] How many probes have actually made it to the surface of Mars? How many missions have not made it?
Jocelyn, I'm not sure exactly how many probes to Mars made it or not. Not all of them were sent by the US, either. But roughly speaking, since the 1960s about 1/2 of the space craft were completely successful. Space exploration is still a very high risk business, but the rewards are well worth the effort.

[ MikeMellon/MarsGlobalSurveyor - 65 - 16:54:01 ]
RE: [LaTeece] I read in your biography that you have several pets. Are you married and do you have any children who are also intersted in space?
I'm not married and have no kids. I do have a girlfriend who is interested in space. My cat might be inetersted in space but she sleeps too much to tell.

[ MikeMellon/MarsGlobalSurveyor - 66 - 16:57:35 ]
RE: [AJ] What would people eat if they lived on Mars? How would they get water?
AJ, people on Mars might get water from the atmosphere, condensing water vapor, or they might dig up ice in the permafrost and melt it - kind of like mining ice. If we pick the right place to land, water from these sources on Mars would be available. Food is a different story. Unless we plan to grow food on Mars in some sort of green house, we would need to bring food with [us] from Earth. There is not much in the way of organic molecules on Mars and certainly nothing to eat.

[ MikeMellon/MarsGlobalSurveyor - 67 - 17:02:10 ]
RE: [Brandon] How cold can it get on Mars?
The coldest it gets on Mars is about -125 celsius (-193 Farenheit). That is the temperature at which the carbon dioxide in the atmosphere freezes onto the surface. This happens in the winter near the polar caps.

[ MikeMellon/MarsGlobalSurveyor - 68 - 17:04:38 ]
RE: [Michelle/StCathRiv] A recent report indicates that early life has recently been found in salt crystals on Earth. Can any of the instruments currently in use on Mars Global Surveyor detect salts on Mars? Has any salt been detected and if so, in what quantities?
The thermal emission spectrometer can detect sulfate and carbonate salts, but not chlorides (like table salt). Salts have been inferred to be present at the Viking Lander sites due to an abundance of sulfur and chlorine in the soil. I think it is only a few percent of the mass of the soil.

[ MikeMellon/MarsGlobalSurveyor - 69 - 17:08:18 ]
RE: [Michelle/StCathRiv] If salt deposits are found on Mars, what kind of scientific theories would follow? Would past oceans have been salty?
Concentrations of salts on Earth occur when salty water evaporates - hence your comment about past oceans. But salts can also be concentrated by freezing, where the salts are ejected from the ice, forming a concetrated brine. The ground water on Mars might also be salty having washed the subsurface soil and rocks for so many years. Finding salts on Mars in high concetrations would not be definative evidence for an ocean.

[ Oran/NASAChatHost - 70 - 17:08:30 ]
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