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MAVEN Ready To Launch Today

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."

55 comments

  1. Oooh by binarylarry · · Score: 2

    I wonder if this is in central?

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

      -1 Funny?

      That's funny!

      --
      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 Anonymous Coward · · Score: 0

      Easy to speculate? Way to hurt everyone's feelings, like just anyone can successfully post on the /

    8. 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.
    9. 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.)

    10. 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.

    11. 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. Meh. by Anonymous Coward · · Score: 0, Offtopic

    Should have sent GRADLE...

  4. 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.

  5. 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.

    --
    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 Anonymous Coward · · Score: 0

      which make things more complicated

      Which is probably why NASA sends a drone to find out.

    3. Re:Not Magnetic Fields by barlevg · · Score: 1

      Ah, thank you. Was wondering about that.

    4. 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
    5. 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!
  6. 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?

    1. Re:Is anyone else taking odds... by Anonymous Coward · · Score: 0

      I'll take you on those odds that neither will collide. Cue HHGTTG, "space is big" joke.

  7. Start simple by fluffythedestroyer · · Score: 0

    I'm certainly no expert at this but how about start going simple. Planets that are far away (distance wise) farther than the earth are too cold, closer are too hot. Maybe its possible at one point in time the Planet Mars had a similar orbit than the earth either a complete similar orbit which was able to substain life or partial orbit so it would be just enough to substain life and/or water at one point and for some reason, its orbit changed so that way it got further away from the sun eventually we know mars as we know today... It's possible that I'm totally wrong as well lol

    1. 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.

    2. Re:Start simple by Anonymous Coward · · Score: 0

      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

      And their point is exactly?

      Sorry, guess I'm being rather pessimistic about trying to figure out how a planet was billions of years ago. We can speculate with far greater accuracy about our own planet's environment back then, and yet speculating about any of it provides us with exactly what usable data today?

      Even if we found out why dinosaurs went extinct, it doesn't change the fact that dinosaurs are extinct, nor will it change the atmosphere on Mars. Pointless activity is pointless. But hey, someone's pockets are being lined, I promise you that...

    3. Re:Start simple by geekoid · · Score: 1

      looked like that now. We would be there.

      --
      The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
    4. Re:Start simple by Anonymous Coward · · Score: 0

      No no no. Proximity to the Sun and solar energy flux have ABSOFUCKINGLUTELY NOTHING TO DO with climate or temperature. The climate of a planet is only affected by the concentration of greenhouse gasses in its atmosphere. PERIOD. Nobody is even debating this anymore. Why do you fucking luddites still walk around like zombies regurgitating this debunked myth that solar forcing has anything to do with surface temperatures or climate?

      Grow the fuck up already.

      Al Gore 2016!

    5. Re: Start simple by Anonymous Coward · · Score: 0

      Why is there always a post like this on any space story? If you want to talk about greed and pointless waste then the military is where you want to be complaining at. NASA's budget is miniscule in comparison.

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

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

    7. Re: Start simple by Anonymous Coward · · Score: 0

      Why is there always a post like this on any space story? Deflecting complaints about NASA being a waste of money to the military being a waste of money.

  8. 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.

  9. thank you MAVEN by Anonymous Coward · · Score: 0

    for teaching me typing via your TEACHES TYPING software in 1987.

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

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

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

    Just like my ex-wife.

  12. 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.
    2. Re:Should we all talk? by Anonymous Coward · · Score: 0

      That is a very well-written article over at NBC!

    3. Re:Should we all talk? by Anonymous Coward · · Score: 0

      From the NBC article:

      Maven is destined to be a team player in another sense: NASA's current Mars orbiters are well into their extended missions, and if one of them fails, Maven can help with the task of relaying data between the rovers on the Martian surface and radio antennas back on Earth. That relay function was considered so essential that the Maven team was exempted from the effects of last month's government shutdown.

  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: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.

  15. What I want to know is: by Anonymous Coward · · Score: 0

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

    1. 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.

  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: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 !

  18. 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

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

    Where are they? "hoyven Maven"

  20. I was told by Anonymous Coward · · Score: 0

    I was told by the dolfins that they brought the water with them when they moved to earth. Along with all the fish.