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MAVEN Ready To Launch Today

Posted by samzenpus on from the go-to-mars dept.

An anonymous reader writes "Mars seems to have gone from being a warm, wet planet with a liquid core (with magnetic fields strong enough to maintain an atmosphere) to a cooled frozen desert-like surface. By gathering information about the Mars upper atmosphere and its magnetic field scientists hope MAVEN can help explain what happened and where the water went."

40 of 55 comments (clear)

  1. Oooh by binarylarry · · Score: 2

    I wonder if this is in central?

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    Mod me down, my New Earth Global Warmingist friends!
    1. Re:Oooh by binarylarry · · Score: 1

      -1 Funny?

      That's funny!

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      Mod me down, my New Earth Global Warmingist friends!
    2. Re:Oooh by bigwheel · · Score: 1

      This is mission control. I said to ask MARVIN http://en.wikipedia.org/wiki/Marvin_the_Martian -- not MAVEN.

    3. Re:Oooh by binarylarry · · Score: 1

      I think that no good fucking rabbit got into our communication system again!

      --
      Mod me down, my New Earth Global Warmingist friends!
  2. Pretty easy to speculate... by Anonymous Coward · · Score: 1, Interesting

    ... and this IS slashdot, after all.

    I think Mars, being small, ran out of natural radio-decay heat sources in its crust and core. Not having enough mass, or enough tectonic activity to churn things up and generate heat, the core solidified, the magnetic field went away, and solar radiation finished them off.

    1. Re:Pretty easy to speculate... by Anonymous Coward · · Score: 2, Informative

      I suspect you mean the necessary mass to retain that heat. The radioactive decay present in the core would continue at the same rate it does on earth ... it's just that it would have started with less, and would still to this day have less. There will be radioactive decay till the end of time (or close enough), if there were radioactive elements present to start with.

    2. Re:Pretty easy to speculate... by Thanshin · · Score: 2

      ... and this IS slashdot, after all.

      There's so much that we share that its time we're aware, this is Slashdot after all.

    3. Re:Pretty easy to speculate... by ShanghaiBill · · Score: 4, Interesting

      The radioactive decay present in the core would continue at the same rate it does on earth ... it's just that it would have started with less, and would still to this day have less.

      But Mars probably started with less radioactive material. The density of Earth is 5.5 kg/l. The density of Mars is 3.9 kg/l. So something in the early solar system caused more dense elements to end up on Earth rather than Mars. Most geothermal heat is caused by the decay of Thorium. Thorium is very dense, and is probably present in significantly higher concentrations on Earth, compared to Mars.

    4. Re:Pretty easy to speculate... by Anonymous Coward · · Score: 1

      That would be the large, moon-like object that impacted and gave us our iron core, with sufficient mass and spin to impart a magnetic field. Current speculation is that the mass is the primary factor in Earth retaining it's atmosphere and Mars losing it's, not the magnetic field as has been previously thought.

    5. Re:Pretty easy to speculate... by olsmeister · · Score: 3, Informative

      There is a theory that early in the Earth's history it was struck by a Mars-sized body, blasting off a large portion of the crust and mantle (incidentally forming the moon) and leaving behind a relatively large metal-rich core.

    6. Re:Pretty easy to speculate... by ShanghaiBill · · Score: 2

      The moon has a density of 3.3kg/l, lighter than either Earth or Mars, so that makes sense.

      Can someone please email the MAVEN team, and let them know that Slashdotters have already figured everything out, and they can cancel the launch?

    7. Re:Pretty easy to speculate... by operagost · · Score: 1

      What explains why the most dense elements on Earth can be found on the internet?

      --

      Gamingmuseum.com: Give your 3D accelerator a rest.
    8. Re:Pretty easy to speculate... by Jane+Q.+Public · · Score: 1

      I think Mars, being small, ran out of natural radio-decay heat sources in its crust and core. Not having enough mass, or enough tectonic activity to churn things up and generate heat, the core solidified, the magnetic field went away, and solar radiation finished them off.

      Curiousity recently found a (relative) boatload of frozen water all over, in the soil, just under the surface. I forget what the estimate was but it was something like 7 liters per cubic meter of soil... which is quite a lot, really. (Granted, a cubic meter is a lot of soil but 7 liters is nothing to sneeze at either.)

    9. Re:Pretty easy to speculate... by Convector · · Score: 1

      Earth already had its iron core at the time of the Moon forming impact. Most of the impactor accreted onto the Earth and the cores of the two bodies merged (Canup and Asphaug, 2001, Nature). A fraction of the silicate crust and mantle of the impactor and target was ejected into orbit. That debris accreted into the Moon. Since it is largely made of the silicate portion of the original bodies, it is depleted in metal, and has a relatively small core.

    10. Re:Pretty easy to speculate... by Convector · · Score: 1

      A few points of clarification.

      1. The major heat-producing elements are all lithophiles, preferentially bounding to silicates. So there's virtually no radioactive decay in the core. It's all in the crust and mantle.

      2. Thorium is an important heat source now due to its long half-life (14 Gy IIRC). But back in the day, Uranium and Potassium-40 were much more abundant, and produced the majority of the radioactive heating.

      3. Assuming the Earth and Mars initially had similar bulk compositions, they would have similar rates of radioactive heating. But Mars surely cooled more quickly. The heat production scales as the mass, and therefore the volume. Heat loss scales as the surface area. So smaller planets have the lower surface to mass ratio and cool more quickly.

  3. Live Coverage by Ashenkase · · Score: 5, Informative

    http://spaceflightnow.com/atlas/av038/status.html

    Any other links out there? I generally use Spaceflight Now for the text updats along with the live feed.

  4. Not Magnetic Fields by camperdave · · Score: 2

    Magnetic fields are not what holds an atmosphere. Gravity does. Consider Venus. It does not have a magnetic field, yet it has quite a thick atmosphere.

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    When our name is on the back of your car, we're behind you all the way!
    1. Re:Not Magnetic Fields by wonkey_monkey · · Score: 3, Informative

      No, but they do deflect the solar wind, which can contribute to atmospheric loss (but then there are other also interactions with the solar wind which make things more complicated).

      --
      systemd is Roko's Basilisk.
    2. Re:Not Magnetic Fields by barlevg · · Score: 1

      Ah, thank you. Was wondering about that.

    3. Re:Not Magnetic Fields by Gavagai80 · · Score: 3, Interesting

      Venus does have an induced magnetosphere which limits its atmospheric losses... and it has lost its water content to solar wind.

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      This space intentionally left blank
    4. Re:Not Magnetic Fields by camperdave · · Score: 2

      The induced magnetosphere around Venus is caused when the charged particles of the solar wind are deflected around the planet. Mars also has the same type of induced magnetosphere. As a matter of fact, the observation of Mars' induced magnetosphere is what lead to the conclusion that the planet doesn't have a significant magnetic field of its own.

      --
      When our name is on the back of your car, we're behind you all the way!
  5. Is anyone else taking odds... by tlambert · · Score: 1

    Is anyone else taking odds... on whether or not they're going to smack the thing into the Indian probe?

  6. Anyone else wondering by Anonymous Coward · · Score: 1

    What was used to _build_ maven?

    1. Re:Anyone else wondering by laie_techie · · Score: 1

      What was used to _build_ maven?

      My guess would be Hudson was somehow involved.

  7. Re:Start simple by SternisheFan · · Score: 1
    They think Mars looked like this (4 Billion years ago)...

    http://www.nasa.gov/content/goddard/nasa-video-illustrates-maven-missions-investigation-of-a-lost-mars/#.UoTqxLxq61s

  8. Mmmmmmmm.... by kaizendojo · · Score: 1

    ....cooled frozen-dessert like surface.....

  9. Re:Start simple by pr0fessor · · Score: 1

    Sounds a little to Hollywood so here is another Hollywood scenarios. This mystery continues on for centuries turning into millenniums until earth develops time travel to go back in time and harvests the resource to repair an ailing earth devastated by global warming, etc... Carefully they leave no trace of their visit and propagate the mystery what happen to Mar's resources.

  10. From warm and wet to frozen, barren and dry. by Anonymous Coward · · Score: 1

    Just like my ex-wife.

  11. Should we all talk? by Nexus7 · · Score: 2

    MAVEN's going to arrive around the same time as Mangalyaan, assuming both do arrive. The arrival rate at Mars is pretty low (with NASA having the best one, 70%). It's going to study the upper atmosphere, just as Mangalyaan plans to. This cost NASA $670 M, at a time when Congress is cutting everything like it (Comments about republicans and science withheld - Editor).

    I really hope these guys talk. I understand descriptions in popular media blur the details, but there seems to be a lot over overlap here.

    1. Re:Should we all talk? by Antipater · · Score: 3, Insightful
      The article from NBC mentions that there will be some cooperation.

      The teams for Maven and Mangalyaan plan to collaborate in their studies of the Red Planet's atmosphere. For instance, there's been some evidence that methane is being released into the Martian atmosphere, which could hint at biological activity. Curiosity hasn't detected any methane at the surface, and Maven won't be measuring methane because that doesn't mesh with the mission's scientific goals. But Mangalyaan can take a closer look at the methane question, and its results could add to Maven's models.

      --
      Everything is better with chainsaws.
  12. Re:Start simple by geekoid · · Score: 1

    looked like that now. We would be there.

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    The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
  13. Thought we were talking about a Java build by sproketboy · · Score: 2

    It is newsworthy that you can get a build to work with Maven. /s

  14. Re:thank you MAVEN by TechyImmigrant · · Score: 1

    Beavis Maven taught you to type?
    Or was it Beacis Macon?
    Or was it Meavis Bacon? I like bacon.
     

    --
    I should use this sig to advertise my book ISBN-13 : 978-1501515132.
  15. Re:This cost NASA $670 M, at a time when Congress by CrowdedBrainzzzsand9 · · Score: 1

    Cheap if you ask me. That's about what it cost to delelop the 'affordable health care' web site.

  16. Another launch tomorrow by IWantMoreSpamPlease · · Score: 1

    NASA will be launching another rocket, a Minotaur, from Wallops Island: http://www.nasa.gov/content/air-force-minotaur-rocket-launching-from-virginia-november-19/ I will be photographing the night launch and should have some good pics up. Check my journal for them, there may also be Air Force interviews after the launch, I'll see if I can get some words in as well

    --
    So rise up, all ye lost ones, as one, we'll claw the clouds.
  17. Re:What I want to know is: by laie_techie · · Score: 1

    What does a cooled, frozen dessert-like Mars taste like?

    Battered and deep-fried Mars is much better.

  18. Re:Start simple by BullInChina · · Score: 1

    Wait a minute. I seem to have lost my playbook. I thought it was Bushes fault?

  19. Re:This cost NASA $670 M, at a time when Congress by tizan · · Score: 1

    Which in turn cost ~1% of NSA's budget $50B and they can't keep a secret !

  20. Mars, or How To Maintain an Atmosphere by walter_f · · Score: 1

    "... with magnetic fields strong enough to maintain an atmosphere"

    I guess this concept works best with an atmosphere that consists of magnetic nitrogen, magnetic oxygen, a dash of magnetic carbon dioxide and so on.

    Sounds fancier than poor old gravity maintaining a boring non-magnetic atmosphere.

    "Let's sing another song, boys. This one has grown old and bitter."
    - Bob Dylan

  21. Oblig Prof Frink jokes? by JamieIanMacgregor · · Score: 1

    Where are they? "hoyven Maven"