Live From Mars WebChat

Date: December 18, l996

Featuring: Greg Wilson
Planetary Geologist on the
Mars Pathfinder mission


Jessie/CJHS: . . . . Wed, Dec 18, 9:01AM PDT (-0700 GMT). . . [65 ] What are some of the most interesting things you have found out about the geology of Mars and Venus and the wind tunnels?

Speaker: . . . . Wed, Dec 18, 9:04AM . . . [92 ] Good morning, Greg.

Speaker: . . . . Wed, Dec 18, 9:04AM . . . [93 ] : Good morning, everybody. I'm sorry about all the technical problems we are having, but I'm happy to be here and I look forward to your questions . I saw one question about what do we see about wind blown sand

Chad/CJHS: . . . . Wed, Dec 18, 9:04AM PDT (-0700 GMT). . . [94 ] What is the highest elevation on Mars and the highest elevation on Earth, and how do they compare?

Speaker: . . . . Wed, Dec 18, 9:05AM . . . [95 ] on the different planets. It's very interesting to see that we can study this process on earth, Mars and Venus and it's a pretty special process that we can compare between the three planets

Speaker: . . . . Wed, Dec 18, 9:05AM . . . [97 ] : Greg, I have a question for you from Chad at CJ high school. What is the highest elevation on Mars and the highest elevation on earth, and how do they compare?

Speaker: . . . . Wed, Dec 18, 9:05AM . . . [98 ] : Chad at CJ ofHS, the highest elevation on article is mount everest and that is about 30,000 feet. The highest location on Mars is o limb puss mounds which is some 26 kill lom ters above the main surface of Mars. So on Mars the mountains are much

Speaker: . . . . Wed, Dec 18, 9:06AM . . . [99 ] bigger and I may elaborate on that a little later.

Speaker: . . . . Wed, Dec 18, 9:06AM . . . [101 ] : I'll keep going. Chad, because there are no plate tech tonics on Mars, the Volcano's tend to stay in one location and they just keep through explosive vul canism keep growing and growing to these great heights.

Speaker: . . . . Wed, Dec 18, 9:07AM . . . [102 ] In Hawaii where we have an active kill low way a volcano, the Volcano's are moving along the interface between the tectonic plates, thus they don't get as big. But they are certainly large Volcano's

Speaker: . . . . Wed, Dec 18, 9:07AM . . . [104 ] : Okay. Are there any schools out there? I only see Chad asking questions. I'm sorry it's a little bit slow today.

: . . . . Wed, Dec 18, 9:07AM PDT (-0700 GMT). . . [105 ] Could the strong winds affect the Sojourner's balance while doing scientic experiments?

Speaker: . . . . Wed, Dec 18, 9:07AM . . . [106 ] John ban in Australia, are you out there? Do you have a question for us this morning , .

Speaker: . . . . Wed, Dec 18, 9:08AM . . . [108 ] : I have a question, though I don't know who its from because this person did not put their handle in. But the question says could the strong winds affect the sojourner's balance while doing scientific experiments.

Speaker: . . . . Wed, Dec 18, 9:08AM . . . [110 ] : Great question about sojourn sojourner. Probably not. The winds on Mars while about equally strong to them on earth when particles are moving, most likely during sojourner's mission the winds won't be as strong and we have been predicting this with

Jessie/CJHS: . . . . Wed, Dec 18, 9:09AM PDT (-0700 GMT). . . [111 ] What are some of the most interesting things you have found out about the geology of Mars and Venus and the wind tunnels?

Speaker: . . . . Wed, Dec 18, 9:09AM . . . [112 ] the Mars general circulation model, that the winds during the prime mission of Pathfinder will be between 10 and 15 meters per second which shouldn't affect sojourner at all .

Speaker: . . . . Wed, Dec 18, 9:09AM . . . [114 ] : I have a question for you from jesy at CH High School. What are some of the most interesting things you have found out about the geology of Mars and Venus in the wind tunnels?

Speaker: . . . . Wed, Dec 18, 9:09AM . . . [115 ] : Jesy, from CJ High School, I think the interesting things that I have found in the wind tunnel recently is why we do not find linear dunes on Mars. They are the most common type of dune here on earth, but we have not seen them on Mars. Recent

John Bayne: . . . . Wed, Dec 18, 9:10AM PDT (-0700 GMT). . . [116 ] Hi Greg! Just wondering, if, in the future, NASA plans to build small buildings on Mars, would wind and sand changes be a problem? I mean, would the building risk being "sanded over"?

Speaker: . . . . Wed, Dec 18, 9:10AM . . . [117 ] experiments show in the Martian wind tunnel show that the dunes on Mars of this type would be so small that the viking imager resolution would not have seen them . Speaker: . . . . Wed, Dec 18, 9:11AM . . . [119 ] : I have a question from John ban in Australia. Hi, Greg. Just wondering if in the future NASA plans to build small buildings on Mars. Would wind and sand changes be a problem? I mean, would the building RISC be sand sanded over

Amanda/Breckenridge: . . . . Wed, Dec 18, 9:11AM PDT (-0700 GMT). . . [121 ] There is a formation on Mars called the Inca Ruins. Could these have been caused by winds and erosion? Speaker: . . . . Wed, Dec 18, 9:11AM . . . [122 ] : Question for Australia, great question. I think that's why I have my job. I think we are concerned about the high energy that these particles have when blowing in the high velocity Martian winds, would abrade spacecraft, any human habit tats,

Speaker: . . . . Wed, Dec 18, 9:11AM . . . [123 ] get into our air system. It's a big concern that we didn't have to deal with when going to the moon, but with the Martian atmosphere it's a big concern, and that's what we are looking at.

Speaker: . . . . Wed, Dec 18, 9:12AM . . . [125 ] : I have another question for you from aman da at brek en ridge. There is a formation on Mars called the in ka ruins. Could these have been caused by winds and erosion ?

Speaker: . . . . Wed, Dec 18, 9:12AM . . . [127 ] : Hello, aman da, from Breckenridge. Sorry, but I don't know about the in ka ruins. Maybe you could explain them a little to me and I could come up with some hypothat sees. But I'm really not a big -- I have not

mscherer: . . . . Wed, Dec 18, 9:13AM PDT (-0700 GMT). . . [128 ] what would be the best way to get a job with nasa?

Speaker: . . . . Wed, Dec 18, 9:13AM . . . [129 ] studied Mars for very long. Maybe you know more about this than I do.

Speaker: . . . . Wed, Dec 18, 9:13AM . . . [131 ] : I have another question for you from M shearer. What would be the best way to get a job with NASA?

Speaker: . . . . Wed, Dec 18, 9:13AM . . . [132 ] : To M shear a, a lot of people who work for NASA do not work as a civil servant or a NASA employee, but we are contractors. I am a contractor and I'm with a university, and I would think that working through a university as a graduate student or a

Sarah/CJHS: . . . . Wed, Dec 18, 9:14AM PDT (-0700 GMT). . . [133 ] How will you know what kind of rock the rover is examining on Mars?

Speaker: . . . . Wed, Dec 18, 9:14AM . . . [134 ] faculty research associate is the best way to get a job with NASA right now .

Speaker: . . . . Wed, Dec 18, 9:15AM . . . [136 ] : Okay. I have a question for you from Sarah at CJ High School School. How will you know what kind of rock the rover is examining on Mars?

Speaker: . . . . Wed, Dec 18, 9:15AM . . . [137 ] : Sarah at CJ High School, we will image the surface of the Pathfinder landing site with the camera to identify target rocks and we will take different spec tra or look at rocks with different wavelengths of light to try to determine what are the

Mark S: . . . . Wed, Dec 18, 9:15AM PDT (-0700 GMT). . . [138 ] Greg - in your wind studies, have you discovered things on Mars like tornadoes, hurricanes, or similar vortexes?

Speaker: . . . . Wed, Dec 18, 9:15AM . . . [139 ] best candidate rocks to look at. The rover then will go to those rocks and place the alpha proceed tron x-ray spectrometer onto the rocks and it will tell us what kind of rock it is, hopefully. It's a lot harder to do in practice than it is over this Web chat as I described .

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:16AM PDT (-0700 GMT). . . [143 ] mark, we see a lot of dust devils on mars...maybe other complex weather patterns..just not enought data now

Sandy/NASA Chat Host: . . . . Wed, Dec 18, 9:18AM PDT (-0700 GMT). . . [144 ] Greg: Can you tell us about the windsocks you made for Mars. Are they like the windsocks at airports?

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:19AM PDT (-0700 GMT). . . [145 ] i didn't make them, some talented tech. at arizona State made them, have you been to my web page, it was some cool pictures of them.

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:20AM PDT (-0700 GMT). . . [146 ] not windsocks like at airports, more like up-side-down cones that are sensitive to the low density martian winds

Speaker: . . . . Wed, Dec 18, 9:20AM . . . [147 ] : So I think. Why don't you type in your answer to that.

Sandy/NASA Chat Host: . . . . Wed, Dec 18, 9:21AM PDT (-0700 GMT). . . [148 ] Speaker: The answer has been typed in.

Jessie/CJHS: . . . . Wed, Dec 18, 9:21AM PDT (-0700 GMT). . . [149 ] What are some of the most interesting and large landforms you have discovered, researched, or heard about?

Mark S: . . . . Wed, Dec 18, 9:21AM PDT (-0700 GMT). . . [150 ] Greg - will the rover be able to capture (as in read/analyze) airborne particles in Mars winds?

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:22AM PDT (-0700 GMT). . . [152 ] jessie, i think the sand dunes in the north polar regions are very interesting. i haven't discovered anything yet, but i am hoping to.

Sandy/NASA Chat Host: . . . . Wed, Dec 18, 9:22AM PDT (-0700 GMT). . . [153 ] Turn Speaker OFF, please. Thanks!

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:23AM PDT (-0700 GMT). . . [154 ] mark s. the imp camera will look at the sun through-out the day and look at the dust loading by seeing how bright the sun it. its a pretty neat expermient

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:24AM PDT (-0700 GMT). . . [155 ] what a students out there studing about mars???

Amanda/Breckenridge: . . . . Wed, Dec 18, 9:25AM PDT (-0700 GMT). . . [156 ] What are some of the routine tasks you perform in connection with the Pathfinder project?

Chad/CJHS: . . . . Wed, Dec 18, 9:25AM PDT (-0700 GMT). . . [157 ] When was Olympus Mons discovered, by whom, and in what year?

John Bayne: . . . . Wed, Dec 18, 9:25AM PDT (-0700 GMT). . . [158 ] Greg - For the "sand" on Mars, what differences are there between Mars sand and the kind you could find on a beach on Earth?

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:27AM PDT (-0700 GMT). . . [159 ] i thinks the big difference is that sand on mars is basalt, not quarts sand found on most beachs...the black sandy beaches in hawaii would be like the sand on mars...because of all the valcanos

Sandy/NASA Chat Host: . . . . Wed, Dec 18, 9:27AM PDT (-0700 GMT). . . [160 ] Good questions everyone!

Kelly: . . . . Wed, Dec 18, 9:27AM PDT (-0700 GMT). . . [161 ] Hello, I'm new here. I heard that in a duststorm on mars, the grains are so fine it is like tobacco smoke. Is that true? If so, why all the concern about duststorms?

Kelly: . . . . Wed, Dec 18, 9:28AM PDT (-0700 GMT). . . [162 ] I just read about the windsocks you worked on for Pathfinder. They look like cones with tubes. Can you please explain how they work? Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:28AM PDT (-0700 GMT). . . [163 ] amanada b. right now, we are just sitting back and watching the flight team do their thing, when we get to mars, we will be planing (24 hours a day) experiments on the surface

Kelly: . . . . Wed, Dec 18, 9:29AM PDT (-0700 GMT). . . [164 ] Also, one more about the windsocks. You said that if you didn't fix a problem in 3 weeks, you would be kicked off of the spoacecraft. Were you serious? Would the experiment have been replaced? And how can they make big changes like that at the last moment?

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:30AM PDT (-0700 GMT). . . [165 ] chad, olm. mons was discovered by the marinar 9 team back in 1974, i think....i not sure just one person get credit for! it take a team, and we share the credit!

Mark: . . . . Wed, Dec 18, 9:30AM PDT (-0700 GMT). . . [166 ] Greg, what is dust loading? Is that amount of particles per area (like a square meter)?

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:31AM PDT (-0700 GMT). . . [167 ] kelly, the windsocks look like cones and tubes because... the tubes counter balance the cone, so that the windsocks center of mass is just slightly below the pivot point, thus making them very sensitive to the thin winds on mars

Sarah/CJHS: . . . . Wed, Dec 18, 9:31AM PDT (-0700 GMT). . . [168 ] How long will it take you to see the rock the rover is "sniffing"?

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:32AM PDT (-0700 GMT). . . [169 ] hi kelly, very serious about getting kicked off...we were and add on experiment, and the main experiments like imp, asi/met, and apxs have to keep on sechedule

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:33AM PDT (-0700 GMT). . . [170 ] mark, dust loading is mass per volume of atmosphere...good question

Mark: . . . . Wed, Dec 18, 9:34AM PDT (-0700 GMT). . . [171 ] Thanks Greg.

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:34AM PDT (-0700 GMT). . . [172 ] sarah, we up load, and down load commands 4 times a day a martian day, so i guess we will seem them every 3 hours or so

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:35AM PDT (-0700 GMT). . . [173 ] they everyone, what do you think causes the great dust storms on mars, and why we don't see things like that on earth?

Jessie/CJHS: . . . . Wed, Dec 18, 9:35AM PDT (-0700 GMT). . . [174 ] Are Earth, Mars, and Saturn's moon, Titan, the only places you now beleive are the only planets or moons that have aeolion processes?

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:36AM PDT (-0700 GMT). . . [175 ] jessie, you need a solid surface and an atmosphere to have aeolian processes, what planet have you forgotten?

Sandy/NASA Chat Host: . . . . Wed, Dec 18, 9:37AM PDT (-0700 GMT). . . [176 ] The question from Greg Wilson was to all of you out there--- Any Answers????

Amanda/Breckenridge: . . . . Wed, Dec 18, 9:37AM PDT (-0700 GMT). . . [177 ] What kind of work did you do in Africa?

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:38AM PDT (-0700 GMT). . . [178 ] amanda, i did irrigation and soil conservation work

Sandy/NASA Chat Host: . . . . Wed, Dec 18, 9:40AM PDT (-0700 GMT). . . [179 ] Hey is anyone out there?

Tim McCollum/CJHS: . . . . Wed, Dec 18, 9:41AM PDT (-0700 GMT). . . [180 ] Sandy, Andrea and Greg - End of class at this end. Thanks so much for your time. Happy Holidays to you all!! John Bayne: . . . . Wed, Dec 18, 9:42AM PDT (-0700 GMT). . . [181 ] This is just a guess, but I think that the sand moves around a lot easier on Mars because the gravity pull isn't as big. ...Is that right?

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:42AM PDT (-0700 GMT). . . [182 ] hey everyone...enjoy the holiday break....see ya on mars next year...got Pathfinder!

Mark: . . . . Wed, Dec 18, 9:43AM PDT (-0700 GMT). . . [183 ] Re: Greg's question to everyone about what causes dust storms on Mars: my guess is there's no vegetation to control erosion, so the planet is a giant desert, and thus there's a lot of potential free-floating sand and dust.

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:43AM PDT (-0700 GMT). . . [184 ] hey john, gravity is important...but the winds are lighter

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:44AM PDT (-0700 GMT). . . [185 ] mark, i thiny you are correct about vegetation, but water is the most important

Mark: . . . . Wed, Dec 18, 9:45AM PDT (-0700 GMT). . . [186 ] Greg - do you mean water covering significant surface areas is important to control dust (as in earth)?

John Bayne: . . . . Wed, Dec 18, 9:46AM PDT (-0700 GMT). . . [187 ] Oh, okay. Is that because the sand doesn't "stick" to itself as much?

Sandy/NASA Chat Host: . . . . Wed, Dec 18, 9:46AM PDT (-0700 GMT). . . [188 ] Thanks everyone for your participation today. Happy Holidays. See you Jan. 6 for the next chat.

Sandy/NASA Chat Host: . . . . Wed, Dec 18, 9:47AM PDT (-0700 GMT). . . [189 ] Greg is still here...

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:47AM PDT (-0700 GMT). . . [190 ] john, correct! but when it is really dry, electrostatics start sticking particles together!

Mark: . . . . Wed, Dec 18, 9:47AM PDT (-0700 GMT). . . [191 ] Bye Sandy, and thanks to Greg and all for another good chat.

John Bayne: . . . . Wed, Dec 18, 9:47AM PDT (-0700 GMT). . . [192 ] What are electrostatics?

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:48AM PDT (-0700 GMT). . . [193 ] hey john, how is everything in australia? thanks for joining us

John Bayne: . . . . Wed, Dec 18, 9:49AM PDT (-0700 GMT). . . [194 ] How's Australia? HOT!!! (It's summer down here, and it's 4 in the morning and it's still over 100 degrees!)

:-) Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:49AM PDT (-0700 GMT). . . [195 ] john, good question...van wals forces....exchange of electrical charges...for the same reason your hair stands up, or your hand sparks on dry windy days

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:49AM PDT (-0700 GMT). . . [196 ] hey john, stay cool....

John Bayne: . . . . Wed, Dec 18, 9:50AM PDT (-0700 GMT). . . [197 ] Oh - is that the full name for static?

Sandy/NASA Chat Host: . . . . Wed, Dec 18, 9:51AM PDT (-0700 GMT). . . [198 ] John: Don't get sunburned. See you Jan. 6 for another WebChat. Happy Holidays!

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:51AM PDT (-0700 GMT). . . [199 ] bye sandy...enjoyed myself

John Bayne: . . . . Wed, Dec 18, 9:52AM PDT (-0700 GMT). . . [200 ] Okay, thanks heaps Sandy + Greg. That was a great chat! (I might be out in the bush Jan 6, I'm not sure yet)

Greg Wilson/NASA Ames: . . . . Wed, Dec 18, 9:52AM PDT (-0700 GMT). . . [201 ] john, it is electrical charge that is not moving "static"...when it moves, you get the spark!

Sandy/NASA Chat Host: . . . . Wed, Dec 18, 9:52AM PDT (-0700 GMT). . . [202 ] Bye Greg. Thanks so much for spending the hour will us today. We look forward to chatting with you again soonh :-)

Frank: . . . . Wed, Dec 18, 9:53AM PDT (-0700 GMT). . . [36 ] When I was in high school and decided to be a botanist, I had no idea that it would give me the chance to see so many different places in the world. I have visited about 54 countries, and most of that travel was to various meetings, etc. Botanists who study the _kinds_ of plants instead of how they function may travel even more.


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