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Space Science

NASA Says Mars Once "Drenched With Water" 1048

NASA is currently holding a press conference (carried live on NASA TV) where they are discussing findings from the Mars rovers. They are saying that the crater that the second rover has landed in has convincing evidence that it was once drenched or covered in liquid water. They cite the tiny spherules, odd holes in the rocks, sulfur in the spectrometric analyses, and evidence of an iron sulfate hydrate (a hydrate is a chemical compound which includes water molecules in the crystal lattice). Update: 03/02 19:45 GMT by M : CNN has a story, or see the NASA press release.
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NASA Says Mars Once "Drenched With Water"

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  • Key point (Score:5, Interesting)

    by Mukaikubo ( 724906 ) <gtg430b.prism@gatech@edu> on Tuesday March 02, 2004 @02:14PM (#8443226) Journal
    If these rocks are sedimentary, then, as Squyres said, that has to be our main target for a sample return mission. Because sedimentary rocks are going to have fossils.
    • Re:Key point (Score:5, Insightful)

      by RLW ( 662014 ) on Tuesday March 02, 2004 @02:15PM (#8443240)
      if there was life to swim in those seas.
      • Re:Key point (Score:5, Insightful)

        by Mukaikubo ( 724906 ) <gtg430b.prism@gatech@edu> on Tuesday March 02, 2004 @02:16PM (#8443269) Journal
        Very true. If there was life in this 'ocean', then it's very likely fossils are in sedimentary rocks in that region. If there are no fossils? Absence of evidence is not evidence of absence, but it'll be a really curious coincidence.
        • Re:Key point (Score:5, Interesting)

          by Madcapjack ( 635982 ) on Tuesday March 02, 2004 @02:46PM (#8443786)
          >Very true. If there was life in this 'ocean', then >it's very likely fossils are in sedimentary rocks >in that region. If there are no fossils? Absence of >evidence is not evidence of absence, but it'll be a >really curious coincidence.

          I'm not sure how much of a fossil bacteria-like creatures would leave behind. There might have been life, but still be no discernible fossils (even assuming that fossils would have been preserved). Chemical signature would be more likely method of identification. Then again, we might find fossils and not even recognize them! Life need not be organic. For example, A.G. Cairns-Smith's book "Genetic Takeover and the mineral origins of life" argues that the first forms of life on earth were colloidal clay organisms without organic chemistry. If Cairns-Smith is correct, then perhaps we should be looking for something like that on Mars instead.

          • Re:Key point (Score:5, Interesting)

            by mikerich ( 120257 ) on Tuesday March 02, 2004 @03:15PM (#8444146)
            Chemical signature would be more likely method of identification.

            One good way that has been used here on Earth is to look for isotopic anomalies in the carbon 12/carbon 13 balance. Life preferentially selects the lighter carbon 12 isotope, so carbon minerals in rocks show carbon 12 enrichment.

            Graphite found in 3.85 billion year old gneiss from Greenland is suspected of being organic in origin from isotopic evidence, even though the original rock has been distorted almost beyond recognition. Since these are the oldest rocks known on Earth, it seems reasonable to attempt similar techniques on Martian rocks when we have some decent samples.

            Best wishes,
            Mike.

          • by Mr. Underbridge ( 666784 ) on Tuesday March 02, 2004 @03:18PM (#8444180)
            I'm not sure how much of a fossil bacteria-like creatures would leave behind. There might have been life, but still be no discernible fossils (even assuming that fossils would have been preserved). Chemical signature would be more likely method of identification. Then again, we might find fossils and not even recognize them! Life need not be organic. For example, A.G. Cairns-Smith's book "Genetic Takeover and the mineral origins of life" argues that the first forms of life on earth were colloidal clay organisms without organic chemistry. If Cairns-Smith is correct, then perhaps we should be looking for something like that on Mars insteI'm not sure how much of a fossil bacteria-like creatures would leave behind. There might have been life, but still be no discernible fossils (even assuming that fossils would have been preserved). Chemical signature would be more likely method of identification. Then again, we might find fossils and not even recognize them! Life need not be organic. For example, A.G. Cairns-Smith's book "Genetic Takeover and the mineral origins of life" argues that the first forms of life on earth were colloidal clay organisms without organic chemistry. If Cairns-Smith is correct, then perhaps we should be looking for something like that on Mars instead

            Actually, bacteria do in fact leave fossil records [berkeley.edu]

            I don't know much (actually, anything) regarding purported non-carbon "life," but regular ol' bacteria can leave fossils, believe it or not.

        • Re:Key point (Score:5, Interesting)

          by tigersha ( 151319 ) on Tuesday March 02, 2004 @02:58PM (#8443938) Homepage
          Purely out of interest, what are the chances (in percentage) that the average sample of, say 1 kg of earth based sedinmentary rock would have fossils in it?
          • Re:Key point (Score:5, Informative)

            by mikerich ( 120257 ) on Tuesday March 02, 2004 @03:22PM (#8444231)
            Purely out of interest, what are the chances (in percentage) that the average sample of, say 1 kg of earth based sedinmentary rock would have fossils in it?

            Depends on the type of rock and what scale you are looking at. For instance if you look at a wind-blown sandstone you'll be hard pushed to find a fossil on any scale, look at a marine sandstone and there is a good chance of finding something.

            But then you have certain limestones which are almost pure fossil contents - fractured shells and the like - all the way through to materials like chalk or diatomaceous clay which are made entirely from microscopic fossil shells.

            So the answer from a geologist is - it depends where you look and how hard.

            Best wishes,
            Mike.

          • Re:Key point (Score:5, Informative)

            by Anonymous Coward on Tuesday March 02, 2004 @04:55PM (#8445307)
            It would be highly variable. In a limestone or chert composed entirely of macroscopic or microscopic shells, it would be nearly 100% fossils -- the rock is *made* of biological remains. These deposits can comprise cubic kilometres of rock over vast areas on Earth. In other sedimentary rocks, fossil content would be lower, or almost zero (e.g., wind-deposited sands are pretty poor). Fossil content is highly variable, and depends upon the geological environment at the surface, the age (e.g., Phanerozoic is much richer in fossils than the Precambrian), and biological factors, as well as the scale of the observations (macroscopic versus microscopic). It also depends greatly on the compositions in the original organism -- did it produce a mineral shell, did it have tough organic material that preserves easily (e.g., spores and pollen)? Hell, there are cases where fossils are known from igneous rocks (e.g., trees encased in lava flows) and plenty of metamorphic rocks too (e.g., just about any fossiliferous sedimentary rock can be metamorphosed to a degree before the fossils are destroyed). Bacterial fossils can occur just about anywhere that suitable mineralization is simultaneously occurring, but they can be tricky to distinguish from non-biological processes (even on Earth, where we *know* there is/was life). Some biological molecules are also recognizable ("biomarkers"), even if the body of the organism is not preserved.

            So, I don't have a good answer for, but based on intuition, I would guess between 1 to 10% on average for Earth. There are vast areas, however, where you could drive for miles and find 100%, or 0%. Because the distribution is so variable, and we can only speculate on the range of likely environments and rock types on Mars, this would not be much of a guideline.

            One thing is for certain, though -- it would take more than a couple of good rovers to eliminate the possibility for Mars.

      • Re:Key point (Score:5, Insightful)

        by Valdrax ( 32670 ) on Tuesday March 02, 2004 @02:28PM (#8443513)
        "Swim" is a sufficiently vague term to apply well.
        Don't forget that bacteria can leave fossils too.
    • by Anonymous Coward on Tuesday March 02, 2004 @02:15PM (#8443247)
      > sedimentary rocks are going to have fossils. ... and fossils means fuel, which in turn means they must have WMDs.
      • by mark-t ( 151149 ) <markt AT nerdflat DOT com> on Tuesday March 02, 2004 @02:18PM (#8443321) Journal
        sedimentary rocks are going to have fossils. ... and fossils means fuel, which in turn means they must have WMDs.
        Right... and fossil fuels mean more greenhouse gasses, which causes the temperature to rise...

        Egad!!! We may have just found a way to teraform mars! ;)

        • by MAXOMENOS ( 9802 ) <mike@nOspAM.mikesmithfororegon.com> on Tuesday March 02, 2004 @02:22PM (#8443410) Homepage
          This would be great news for the space program, as Bush would make the invasion and conquest of Mars a national priority.
        • by Dread_ed ( 260158 ) on Tuesday March 02, 2004 @05:09PM (#8445449) Homepage
          I am really tired of people "looking for life on (insert planet/moon name here)." If it can't jump up and say "Howdy!", prance around in a skipmy outfit like that Vulcan chick from Enterprise, or shoot a ray-gun with a tentacled appendage, who cares! Evolution is king, baby: let's not coddle those weak little Martian organisms. If they can't handle the competetion with some strapping Earth-born organisms...fuck em!

          Think about how long it takes to terraform a planet. Shouldn't we have started by now? It's past time to seed some plants to eat the carbon dioxide, release some oxygen and let them begin digging the water out of the earth and releasing it into the atmosphere.

          Speaking of plants, I wonder if tossing cactus/sensamilla seeds out of a baloon bourne lander would be a good way of finding water. Those plants are pretty hardy, and anywhere the plants start to grow would potentially have water sources near the surface. I bet I could devise some wicked experiments to carry out on Mars with plants that were modified genetically to withstand the harsher conditions.

          If only the scientific community would grow some gonads we would have a great decade of science and experimentiton ahead of us.

          What is the matter officer? I have obeyed all of your silly Earth laws!
    • Re:Key point (Score:5, Insightful)

      by wankledot ( 712148 ) on Tuesday March 02, 2004 @02:18PM (#8443318)
      If we brought back 10 tons of mars rocks, the chances of getting a fossil are still slim to none. Talk about needle in a haystack. Not to mention the fact that you have to land near some of it to begin with.
      • Re:Key point (Score:5, Interesting)

        by Paulrothrock ( 685079 ) on Tuesday March 02, 2004 @02:47PM (#8443796) Homepage Journal
        Which is exactly why we should send a manned mission with a microbiologist or two who can spend a year and a half looking at various types of sediment for hundreds of kilometers.

        NASA has never lost a human in space, so sending them on a 1.5 year mission is actually safer than throwing them to orbit.
        • Re:Key point (Score:5, Insightful)

          by thales ( 32660 ) on Tuesday March 02, 2004 @03:08PM (#8444052) Homepage Journal
          No Manned Missions should be sent to Mars until we are reasoably certain that no life presently exists on the Red Planet.

          Fossils can wait. We don't need to contaminate Mars with the Earth Bacteria that a manned mission would introduce until we are sure there is a very low probility of finding living independantly evolved life.
          • Re:Key point (Score:5, Insightful)

            by DJayC ( 595440 ) * on Tuesday March 02, 2004 @03:37PM (#8444420)
            Couldn't the machines and devices we have sent have just as good of a chance to contaminate Mars than humans?
          • Re:Key point (Score:5, Interesting)

            by Jerf ( 17166 ) on Tuesday March 02, 2004 @03:48PM (#8444591) Journal
            We don't need to contaminate Mars with the Earth Bacteria that a manned mission would introduce until we are sure there is a very low probility of finding living independantly evolved life.

            Why?

            (Don't dismiss this. It's a hard question. Give it some thought.)
            • Re:Key point (Score:5, Insightful)

              by thales ( 32660 ) on Tuesday March 02, 2004 @04:25PM (#8444995) Homepage Journal
              The Origin of life is one of the most important questions facing Science. We have made some good gusses about it, but we are handicapped by only having life from one planet to study. Finding Independantly evolved life would shed light on the questions of how common life is in the Cosmos and how it started. That is far more important than any information that can be gained by having Humans on the Surface of Mars.

              We need probes designed to answer that fundemental question, does life presently exist on Mars before we land Humans there. If we find that there is little likelyhood of Martian Life then it's time for Human Exploration. If we finf that there is life on Mars it needs to be carefully studided before we contaminate the planet with the Bacteria that a manned mission would introduce.

          • by Decaff ( 42676 ) on Tuesday March 02, 2004 @06:07PM (#8445969)
            Mars is already contaminated with Earth Bacteria. There has been significant exchange of materials between Earth and Mars as a result of meteor impacts splashing small bits of each planet into space. It has been demonstrated that lots of bacterial species can cope with the tremendous forces and pressures that these bits would be exposed to, so they could (and almost certainly do) easily survive an interplanetary trip. Discovery of DNA-based life on mars, or anywhere else in the solar system, would not answer the question about whether or not we are alone in the Universe, as all that life is very likely to have come from the same single source.
    • by Danathar ( 267989 ) on Tuesday March 02, 2004 @02:23PM (#8443420) Journal
      Interesting...That means we could possibly come back with a another rover that not only could look for life, but could possibly "repair/rejuvinate" the current rover by 'sweeping" the dust off of the solar panels? I would imagine just leaving the rover would be interesting to engineers and scientists to see what happens to a man made object that sits out in the open for extended periods of time....good information if you want to build stuff on Mars.

      Anybody out there like to comment? Is it a possibility? Could we come back with another rover and get Opportunity working again after it runs out of juice?
      • by SB9876 ( 723368 ) on Tuesday March 02, 2004 @02:27PM (#8443499)
        Unlikely, the uncertainties of the atmospheric entry result in a landing footprint that's (IIRC) a few thousand square miles. The chances that we could get a new rover down within driving range of an existing rover is pretty small. By the time we've got rovers capable of driving those sorts of distances or landings that are accurate enough to make that plan practical, I think that we'd have enough experience that there wouldn't be much to be gained from going back and looking at the old rovers.
      • Anybody out there like to comment? Is it a possibility? Could we come back with another rover and get Opportunity working again after it runs out of juice?

        Opportunity's batteries will be dead (as in won't charge) inside a year of landing. Since the little guy can't rove without a stored supply of juice, he'll be as good as dead. That's actually one reason why scientists had wanted to use an RTG on the mission. An RTG could have kept it running for years, and in fact would have been one of the LAST components to kick the bucket. Sadly, NASA doesn't want another PR problem like with the Cassini probe.

      • by visgoth ( 613861 ) on Tuesday March 02, 2004 @02:38PM (#8443669)
        The next rover should drop solar panels in favor of a much more robust power source. I recommend somthing based on harnessing the heat of decaying heavy elements*.

        *Nuclear power (oooh the scary word!)

      • by JahToasted ( 517101 ) <toastafari@ y a h o o.com> on Tuesday March 02, 2004 @02:39PM (#8443685) Homepage
        If it were as simple as just sweeping off the dust from the solar panels, wouldn't they have jsut built the rovers with a little robotic arm and a broom so they could clean themselves off?
      • by caffiend666 ( 598633 ) on Tuesday March 02, 2004 @03:40PM (#8444456) Homepage

        If there was already an appropriate rover on the way, yes.

        The death of the rovers will likely be slow and gradual. First a camera goes, then the arm, then it doesn't have power to move, then the batteries die, not having enough heat to keep the rover warm at night, the one or two functional devices left only operate during daying hours. Then, eventually, they can only ping the things. And, then everything goes quiet.

        Once the batteries fail, many other components will fail due to lack of heating during night and thermal cycles.

        Decades from now, we might still be getting signals from the rovers. The orbiters from viking lasted over a decade. One of the russian lunar rovers operated for 10 months. I would hate to think we can't surpass what the Soviets pulled off 30 years ago.

        The last successful rover lasted several times longer than it was expected to, in fact the rover outlasted the lander that served as a transmitter and a relay station. Upon death of the lander the Soujourner probe was to try to return to the lander. I wondered how long that thing circled the lander, if it if got back at all.... Part of the reason these rovers are all in one units, capable of communicating with earth (at low baud) on their own, was because the last rover outlasted the lander.

        In the two weeks Spirit was useless a few weeks ago, they were afraid components would fail. Now, try to imagine the years it takes to design/launch/wait on/land rovers? What would keep working? One of NASA's pre-Bush-Space-Initiative goals was to build a robot colony on mars. These rovers are not the start though.

        I for one, would like to see them relaunch at least one rover similar to these in the next launch window. They are (were) planning on relaunching the polar lander. And, it would be nice if the next gen non-nuclear rovers could dust themselves, think $20 wiper blades.

    • by drmike0099 ( 625308 ) on Tuesday March 02, 2004 @02:29PM (#8443542)
      They mentioned that they are going to go check the nearby rock outcropping named "Big Bend" and do basically the same that they did on this rock, in order to see if these rocks were laid down there. I think they're checking exactly that, i.e. whether or not this whole area is laid down with rocks of the same origin (soaked in water), or if they were thrown here by a collision or something.

      They said that they weren't sure if the rocks were sedimentary or not. From the sounds of it they aren't, but they did happen to be "soaked in water" or whatever the quote was, allowing the concretions to form in spaces in already existing rock. They haven't found any evidence of layering yet, as far as I know, which would mean sedimentary.
  • So much... (Score:5, Funny)

    by i.r.id10t ( 595143 ) on Tuesday March 02, 2004 @02:14PM (#8443232)
    ... for CowboyNeil saving money on his auto insurance...
  • I wanted my free shrimp from Long John Silvers! Damn! Info Here [longjohnsilvers.com]
  • Not very surprising (Score:5, Interesting)

    by Z00L00K ( 682162 ) on Tuesday March 02, 2004 @02:15PM (#8443244) Homepage Journal
    That there once has been water on Mars, considering that a lot of comets contains water.
  • gun jumping (Score:5, Funny)

    by kippy ( 416183 ) on Tuesday March 02, 2004 @02:15PM (#8443256)
    I love how this story was posted during the opening remarks of the press conference before they could go into much detail.
  • by The Ancients ( 626689 ) on Tuesday March 02, 2004 @02:15PM (#8443259) Homepage
    Some creative company wants to find, and market this 'untouched natural' water?
  • by AndroidCat ( 229562 ) on Tuesday March 02, 2004 @02:16PM (#8443270) Homepage
    So Mars haven't taken a bath or shower in ages. No wonder they're finding crusty salt brine residue.
  • by mark0 ( 750639 ) on Tuesday March 02, 2004 @02:16PM (#8443273)
    "... the lense on the camera got really fogged up. That's when we really got suspicious."
  • Link to the web case (Score:5, Informative)

    by seann ( 307009 ) <notaku@gmail.com> on Tuesday March 02, 2004 @02:16PM (#8443283) Homepage Journal
    Its not too late to watch: http://www.jpl.nasa.gov/mer/landing.cfm
  • Where did it go? (Score:5, Interesting)

    by gid13 ( 620803 ) on Tuesday March 02, 2004 @02:17PM (#8443292)
    Maybe I'm just an idiot, but where does the water go? Vapour in the atmosphere? Did the hydrogen and oxygen break apart somehow? Chemical reactions with something else? Did it just float off into space? Those all seem unlikely to me, but then, what do I know?
  • by therealcaf ( 697590 ) on Tuesday March 02, 2004 @02:17PM (#8443294)
    can be found here [nasa.gov]
  • by lavalyn ( 649886 ) on Tuesday March 02, 2004 @02:17PM (#8443303) Homepage Journal
    And then there are fossils. Which means the next NASA mission will be funded by Halliburton after all.
  • by Ga_101 ( 755815 ) on Tuesday March 02, 2004 @02:19PM (#8443353)
    To equip 2 Rovers with the best water detecting equipment known to man and how do you find water?

    You get mud stuck to the tyres!

    But in all seriosness, Good on NASA.
    But it certainly makes a more life seeking mission like beagle 2 all the more important.
  • by gfilion ( 80497 ) on Tuesday March 02, 2004 @02:22PM (#8443415) Homepage

    and at the end of the conference, they'll pretend that it's over and say:
    and one more thing... we found life on Mars!

  • by aacool ( 700143 ) <aamanlamba2gmail,com> on Tuesday March 02, 2004 @02:23PM (#8443422) Journal
    Of the elements known to exist in the body, some, possibly all, are necessary to life. They are carbon, hydrogen, nitrogen, oxygen, potassium, sodium, iron, copper, manganese, zinc, magnesium, lithium, phosphorus, sulphur, chlorine, iodine, barium, silicon.

    Also, Methionine is an essential amino acid that is not synthesized by the body and must be obtained from food. It is one of the "sulphur-containing" amino acids and is important in many body functions.

    It is likely that sulphur, coupled with the different ferrous hydrides can produce viable conditions for life.

  • New info (Score:5, Interesting)

    by DarkHand ( 608301 ) on Tuesday March 02, 2004 @02:24PM (#8443447)
    The conference is going on now and theres new news: Not only was there a large amount of water, there's good evidence that it was salty.
  • NASA Press Release (Score:5, Informative)

    by athorshak ( 652273 ) on Tuesday March 02, 2004 @02:24PM (#8443455)
    No link in the article. Here is the press release: NASA Press Release [nasa.gov]
  • by Fragmented_Datagram ( 233743 ) on Tuesday March 02, 2004 @02:34PM (#8443612) Homepage
    Oooh... so maybe humans were originally on Mars... and they screwed up their planet with pollution, overuse of resources, etc., but managed to transport a few people to Earth to start over...
    And maybe we'll look to terraform Mars and move there once we've hosed this planet too. The cycle continues...
    Heh... yeah. Anyway, back to work now.
  • Free Food? (Score:5, Informative)

    by WebGangsta ( 717475 ) on Tuesday March 02, 2004 @02:41PM (#8443707)
    Does this mean that we ARE going to get free jumbo shrimp [longjohnsilvers.com] or not?

    Crap. Fine print says...

    If NASA's Mars Exploration Mission team discovers conclusive evidence that an oceanic body of water currently exists or previously existed on the planet Mars, and an Official Declaration of such existence is made on or before February 29, 2004, Long John Silver's will offer every person in the United States the opportunity to obtain one (1) free Giant Shrimp (Approximate Retail Value of $0.79) ("Free Giant Shrimp") at participating Long John Silver's(R) restaurants in the United States.
    If only they could have booked the conference room for the press conference 2 days ago instead of using it to hold Jerry's retirement party.

    'cause I *really* wanted to have that free jumbo shrimp.

    dammit.

  • by Dutchmaan ( 442553 ) on Tuesday March 02, 2004 @02:43PM (#8443740) Homepage
    Add some mass to the planet for added gravtiy, massive heat increase to melt the ice caps and creat liquid water...

    Make it pay per view to keep it profitable!

    We can call it a Weapon of Mass Creation!

    WE CAN'T LOSE!
  • Is this news??? (Score:5, Interesting)

    by Ektanoor ( 9949 ) on Tuesday March 02, 2004 @02:44PM (#8443749) Journal
    Frankly I'm disappointed. Until now they roam around and claim that the findings are not wholly conclusive:

    "The images obtained to date are not adequate for a definitive answer. So scientists plan to maneuver Opportunity closer to the features for a better look. "We have tantalizing clues, and we're planning to evaluate this possibility in the near future," Grotzinger said.

    Besides hydrated minerals were already hinted by Spirit. One of the very first press releases pointed to that fact. Besides this is not the only weird thing between Opportunity and Spirit outputs. If one compares the first wave from results from Spirit with Opportunity's then it seems that the second robot is clearly giving very thiny results. Until now I could not see broadscale spectral and infrared analysis like the ones Spirit did. Maybe I'm missing something but frankly it seems that data feed from Meridiani goes a long way from it could.

    PS: To those who are discussing theologies... Frankly don't get you people. Try to find a super SF author by the name of Nicolau Cusanus and his bestseller "De docta ignorantia". He already discussed a lot of what you keep rumbling till now...
  • by jazman_777 ( 44742 ) on Tuesday March 02, 2004 @02:58PM (#8443942) Homepage
    they had found some Spice.
  • Jarosite, defined (Score:5, Informative)

    by RobertB-DC ( 622190 ) * on Tuesday March 02, 2004 @03:27PM (#8444297) Homepage Journal
    The NASA scientist held up a sample of Jarosite. For the curious, here's a definition [galleries.com]. Note -- the page referenced has several very cool links for more information.

    THE MINERAL JAROSITE
    Chemistry: KFe3(SO4)2(OH)6, Potassium Iron Sulfate Hydroxide.
    Class: Sulfates
    Group: Alunite
    Uses: Only as mineral specimens.
    Specimens
    Jarosite is not a common mineral. It is closely related to the mineral natrojarosite. Jarosite is isostructural with natrojarosite which means that they have the same crystal structure but different chemistries. In this case, jarosite contains potassium instead of natrojarosite's sodium (natro is derived from the Latin for sodium, natrium, from where sodium gets its symbol, Na). The two minerals are difficult to distinguish without a chemical test.

    Both minerals are isostructural with alunite with a formula of KAl3(SO4)2(OH)6, who lends its name to the Alunite Group of which all three minerals belong.

    The symmetry of jarosite is the same as the members of the Tourmaline Group. Crystals of jarosite however do not form prismatic crystals like those of the typical tourmaline mineral. Jarosite's crystals are more flattened and resemble nearly cubic rhombohedrons. The "rhombohedrons" are actually a combination of two trigonal pyramids.

    PHYSICAL CHARACTERISTICS:
    Color is an amber yellow or brown.
    Luster is vitreous to resinous.
    Transparency: Crystals are transparent to translucent.
    Crystal System is trigonal; 3 m
    Crystal Habits include tabular to flattened rhombohedral looking crystals. The "rhombohedrons" are actually a combination of two trigonal pyramids. Crystals are somewhat scarce and small, more commonly as earthy masses, films or crusts, botryoidal and granular.
    Cleavage is good in one direction but only seen in the larger crystals.
    Fracture is uneven.
    Hardness is 2.5 - 3.5.
    Specific Gravity is approximately 2.9 - 3.3 (average to slightly heavy for translucent minerals, but hard to obtain from crusts)
    Streak is a pale yellow.
    Associated Minerals are barite, turquoise, galena, goethite, limonite, hematite and other iron minerals.
    Notable Occurrences include Jaroso ravine, Sierra Almagrera, Spain and Iron Arrow Mine, Colorado; Maricopa Co., Arizona; Idaho and California, USA.
    Best Field Indicators are crystal habit, associations, color and hardness.
  • Mission Accomplished (Score:5, Informative)

    by QuantumFTL ( 197300 ) * on Tuesday March 02, 2004 @05:47PM (#8445757)
    Here at JPL, it is an interesting mixed feeling the scientists are having.

    On one hand, we've acomplished almost all of the stated goals of the mission. I saw the Long Term Planning briefing and the chart had item after item checked off... only the endurance section was left unfinished.

    Think about it. We landed not one but two fully functional rovers on mars, with the most comprehensive science package ever sent to another world. We have spectrometers of unmatched precision, we have the ability to examine betneath the surface of rocks and outcrops, and we've taken the most detailed pictures of mars ever recorded.

    We've explored rocks and craters and soils, and that was just the first few sols! All of this is an incredible accomplishment, especially considering the track record. The engineering part alone is enough to consider the mission a success.

    But since last week it's been clear to us here that we've found what we were looking for: evidence that clinches the case that Mars was once wet. That's when I say, "Mission Accomplished". That's more than many hoped to find, though we sent the mission as it is primarly because we expected this was *possible* if even somewhat unlikely.

    But we're not done yet. In fact if anything we have more questions to answer now. Mars has never failed to throw curve balls at us. There's all kinds of minerology that we're not sure about. We don't even know yet if this was just ground water, or actually lakes or oceans. But as long as these rovers still have life in them we'll continue to advance our scientific understanding of the planet.

    Regardless of what anyone thinks about the specifics of the President's plan, it's clear that public support for the program is very high now, considering that we have learned from our mistakes and have accomplished more than we could have hoped. I'm very optimistic that future missions will unravel many of the new mysteries we have discovered. It is truely, as they said on the briefing, a great time to be alive. The field of astrobiology is finally beginning to be taken seriously by the scientific community and even the public at large. We have seen that Faster, Better, Cheaper *can* work - as long as we don't try to bite off more than we can chew.

    I don't know when we'll actually have humans on Mars, but I'm hopeful that there's a real chance that in my lifetime (and maybe even my parents') we will find evidence of previous life on Mars. It'd be nice to know we're not quite alone.

    My congradulations to the science team for an incredible discovery, and I extend that to the taxpayers that graciously fund us, and to our supporters in all nations of this earth. We could not have made these discoveries without our valued partners in Europe, and they deserve to share much of the credit.

    I know some of you on slashdot ask why fund the space program. I hope that this makes it clear that you are getting your money's worth. Thanks for all of your support!

    Cheers,
    Justin Wick
    Science Activity Planner Developer
    Mars Exploration Rovers

Let the machine do the dirty work. -- "Elements of Programming Style", Kernighan and Ritchie

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