Washington Post Staff Writer
Monday, April 28, 2008 2:00 PM
Washington Post science writer Marc Kaufman was online Monday, April 28 at 2 p.m. ET to discuss the discovery of what scientists believe may have been hot springs on the planet Mars, a place where primitive kinds of life could have thrived.
A transcript follows.
Marc Kaufman: Good afternoon. We're talking today about Mars, water, and whether some new images from NASA's Mars Reconnaissance Orbiter show the remains of two hot springs that once ran on the Martian surface. I first saw the images at a NASA astrobiology conference earlier in the month -- and some similar ones taken of dry hot springs on Earth -- and they were quite strikingly similar. I fear the images do not hold up as well on a computer or newspaper scale, but hopefully they make a point. On to your questions...
Newbury Park, Calif.: Could it be that the scientist that are studying the surface of Mars, are just "seeing things" in their quest to find something? Or is it a real finding?
And how did the water that once existed in Mars, disapeared?... Was it by evaporation or was it by going underground?... And it could be found as ice?
Marc Kaufman: These are veteran researchers who identified these possible old hot springs, and so I think their findings are significant. That doesn't mean they're correct, and that they'll hold up to further scientific scrutiny. But that's how science progresses -- data, information and theories are put forward and other react. The research has been submitted for publication in a professional journal, and if it's accepted, that will speed the review process. But the images were presented at a major NASA conference, and that means some pretty knowledgeable people thought there was something to it.
As for the mystery of water on Mars, it's pretty well accepted now that liquid water did indeed exist at some point on the surface of Mars. Some believe both liquid and frozen water still exists beneath the surface, and we know that frozen water is found at the poles. But there is no consensus about where the "missing" water -- if it is indeed missing -- might have gone.
Torrance, Calif.: Is this new discovery indicative of life possibilities on Mars?
Marc Kaufman: I think it can be considered a tantalizing but quite preliminary finding that conditions for life may have existed on Mars in the past. Hot springs are well known on Earth as breeding grounds for microbial and other life, and the researchers are working on the assumption that the same could be true on Mars. So there are a number of big "ifs" here. If it actually was a hot spring, then that would be significant. And if hot springs on Mars function as they do on Earth, that would increase the likelihood that they once held life. But the big "if," of course, is that life would have had to form and evolve on Mars to begin with.
Taylor, Mich.: If this true about the hot springs area, would this not be a logical place to send another rover to investigate or a possible manned mission, if and when we have the technology to go to Mars?
Marc Kaufman: Not only manned missions, but robot and rover missions as well. The two researchers, Carlton Allen and Dorothy Oehler of NASA's Johnson Space Center, believe that if these two are former hot springs, then Mars probably has others -- and maybe many others. (Earth has something like 50,000.) The site where these were located is a dusty one, and might be less than optimal for landings. In addition, spectrometers on the orbiter have not found evidence at the site of the kind of minerals that would be expected around a hot springs. So before NASA were to select a site like this one, or others with apparent hots springs, they would have to find out a lot more about mineralology, geology and the like.
Reston, Va.: Is there any possibility that those mounds we're seeing are evidence of ancient Martian groundhogs?
Also, if they actually were hot springs and we can get them restarted, think of the potential impact on the space tourism industry. Who wouldn't love to go for a dip in some nice Martian hot springs and a relaxing steam bath?
Some people may rather go there than West Virgina. And people do go to Iceland for such things, and the landscape's not that much different, is it?
Hope you enjoyed the Science Humor injection and keep up the good work, Marc. This is great stuff, and a very noteworthy discovery.
bc in Reston
Marc Kaufman: A LOL posting for me, and hopefully for you folks as well.
M Street NW, Washington, D.C.: I appreciate that the discovery of extremophiles on Earth has given scientists hope of discovering evidence of life in similar environments on Mars. However, to the extent that the research into extremophiles indicates that these organisms adapted from less harsh environments to fulfill ecological niches, isn't expecting to find extremophiles in similarly harsh environments on Mars misplaced?
Shouldn't the search for life on Mars focus on the most conducive environment for organisms to initially arise?
Marc Kaufman: Interesting point. As I understand it, the research on extremophiles on Earth is driven by 1/the remarkable fact of their survival and 2/what they tell us about the ability of life to survive in environments that scientists did not believe was possible. In that sense, studying extremophiles here is a way to expand our vision when it comes to other planets. If extremophiles here can adapt to life under enormous pressure on the deep ocean floor, near seemingly poisonous underwater vents, and in environments will little or no water, that opens the possibility of equally improbable adaptations on other planets. Scientists wouldn't be looking for the same extremophiles, but for different ones and for extremophiles in general.
Wilmington, N.C.: Can they go in and get a sample of the soil to see if there was water at one time?
Marc Kaufman: NASA is planning a Mars sample return mission for the later part of the next decade. If these and other mounds do indeed turn out to be remnants of hot springs, they would be very attractive targets. And they would be going not just to see if there had been water, but if there had been some form of life as well. Hot springs bring up minerals from below the surface, and minerals are good for preserving fossils. That makes the springs potentially even more attractive to scientists.
Huntington Beach, Calif.: I see the numerous small mounds, which I am assuming are the "springs" in question, however, the large mound looks a lot like a volcano. Is this in a volcanic region? The magazine articles don't specify.
Marc Kaufman: I believe this is not considered a volcanic region. The larger image from the Martian surface actually contained another larger mound or mountain that looked quite a bit like a volcano. But the researchers said they had not been able to determine what it actually was.
Wadsworth, Ohio: what do spectrographic analyses of the hydrothermal deposits reveal about the underlying strata?
Marc Kaufman: The specific area contains a lot of dust, and it appears that is masking what lies on and below the surface. Until that is somehow corrected, or similar mounds are found in less dusty areas, researchers won't be able to make any definitive statements about whether they really were hot springs.
Germantown, Md.: Do you think there may be a change of extraterrestrial life elsewhere?
Marc Kaufman: I presume you mean a "chance" of extraterrestrial life....
I don't have an opinion of my own, but I spent several days recently at an astrobiology conference (sponsored by NASA,) and I found it fascinating. There's much research going on now into the most basic questions--such as "what is life?" "are there other Earths in other solar systems"? and "how can signs of life on distant planets be detected?" -- and many scientists are making real progress. Some of the best scientists in the field believe it's likely that life exists elsewhere, and given the numbers that makes some sense. There are 100 billion stars in the Milky Way, and some 100 billion other galaxies in the observable universe. Since we now know that many of those stars have planets circling them, it seems increasingly likely that some have conditions that could support some form of life.
Los Angeles: When scientists state they are looking for "life" on Mars, do they mean intelligent life, or any form of life? Have there been any indications that there could be microorganisms on Mars or if it such as found, does that count towards what scientists are looking for?
Marc Kaufman: Until fairly recently, scientists and others searching for extraterrestrial life tended to be looking for "intelligent" life. That has changed, and the search now is far more for microbial or simple life forms. But the SETI Institute still runs a program that sends out powerful radio waves in the hope that some intelligent life forms will receive them and respond.
Houston: As if its not bad enough we've DESTROYED this planet and pretty close to destroying ourselves. We've decided to scope out another. It's nice to look but maybe thats the reason its still beautiful...WE'RE NOT THERE.
Marc Kaufman: I've heard more than once that it would be dangerous for humans to actually go to Mars because we would most likely harm it. Given the shape of the Earth, I understand the concern. On the other hand, returning a Mars sample to Earth could pose an as-yet-unknown risk to earthlings, too. I recall the same debate occurred before Apollo landed on the moon, but it seems that the moon remains okay and we're no worse off for the returned moon rocks, either.
Washington DC: Great article - again - Marc...
BUT it would be nice if washingtonpost.com would include the photo(s) discussed in the article WITH the article. I see it's shown here with the chat, but it's a bit more helpful when with the article itself.
Question is: The rovers have a fairly short distance they can really travel... so not knowing the details of the Martian landscape, how far is this formation from where the rovers are today?
washingtonpost.com: The photos are associated with the explanatory graphic that is attached to the story - but here's an easy link: Comparing Martian Mounds to Springs
Marc Kaufman: It's actually relatively close -- about 100 kilometers, I believe. That, however, is way too far for the rover to travel.
As for your point about including the photo with the article online, I checked and it is there, thought under a seperate headline of "Comparing Martian Mounds to Springs."
Washington, D.C.: If Darwinian theory (natural selection and random mutations) adequately explains the emergence of life and origin of new species, then the Phoenix Mission set to land on the martial north pole next month and later NASA and ESA life-probing missions such as the Mars Astrobiology Lab, should discover life on Mars or show that there once was life on Mars perhaps billions of years ago when liquid water may have covered portions of Mars. But if Darwinian natural selection is not the explanation for origins of life, then these spacecraft will not discover indicia of past or present life near or at hot springs or anywhere else on Mars. Do scientists agree that these life-probing spacecraft are up-or-down litmus tests for Darwin's theory? Doesn't Darwinian theory need to be empirically verifiable to count as a scientific theory of emergence or origins as opposed to someone's hunch?
Marc Kaufman: Your question points to a fascinating aspect of the astrobiology field -- that it actually does include subjects ranging from the origins of life to evolution to the long-debated question of whether we're alone in the universe. Regarding Darwinian evolution, I don't think a handful (or even a lot) of missions to Mars or elsewhere would necessarily tell us much. If some form of life is found, it raises the question of whether it has, or will, evolve. But if life forms are not found, that doesn't mean 1/they never existed on Mars 2/they don't exist elsewhere on the planet or the universe and 3/that evolution has not created the world we live in. There's an often-repeated scientific maxim that an absence of evidence is not evidence of absence.
Richmond, Va.: What do you think is the significance of today's announcement that Mars is buying Wrigley?
Marc Kaufman: I think discovery of the "Mounds" put the deal over the top.
Las Vegas, Nev.: I wonder how many people realize the value of space exploration each and everytime we launch be it to the moon or just a satallite orbiting earth..the benefits we gain both medically & electronically..its a wonderful advancement I hope you keep going..with space exploration...we need it. and I for one believe in intelligent life far from earth somewhere...they are out there.
Marc Kaufman: The U. S. has long enjoyed space supremacy in virtually every way, but I recently read a well-researched report by a private space-information company that concluded that we are losing our edge. And this is happening at a time when many other nations are stepping up their efforts in space.
Chico, Calif.: Is there any way to estimate how long the springs have been dry?
Marc Kaufman: I'm told the area has been dry for tens of millions of years. Sounds like a long time, but that is actually considered quite recent in planetary terms.
Many thanks for your good questions.
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