back to article Half-ton space watermelon hints at habitable Martian past

An unusual object recently found on Mars by a NASA robot - said to be "the size of a large watermelon" and to weigh a "half ton or more" - is thought by boffins to provide proof that the Red Planet once had a much denser atmosphere than it does now. NASA close-in image of the 'Block Island' meteorite on Mars Robot rovers and …

COMMENTS

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  1. Steve Swann
    WTF?

    A question... or two...

    Half a ton of nickel/iron compound slamming into the surface of mars at some distant point in the past...?

    Where's the crater?

    How come it's just lying there on the surface when the rest of the this once-atmosphere covered world has been scoured away by the ravages of time?

  2. Sleepy 3
    Alert

    Sod the weathering differences...

    Who made the big footprint, complete with toes, on the right hand side of the rock?

  3. Anonymous Coward
    Alien

    Huge watermelon?

    Most watermelons I see in the market would probably come close to fitting in a one cubic foot box.

    My sources say one cubic foot of granite weighs about 160 lbs, iron abut 460 lbs.

    A very large cast iron watermelon might start to approach half a (short, 2000 lb) ton.

  4. D@v3
    Terminator

    Spirit

    "help, help, I've fallen and i can't get up"

  5. Anonymous Coward
    Anonymous Coward

    @ Steve Swann

    'Where's the crater?'

    Doesn't need to be one; meteorites don't always arrive near vertically; sometimes they skip across the atmosphere like a stone over a pond, gradually descending at a very low angle and coming to rest at relatively low speed.

    Actually, when I first saw the images this meteorite reminded me of the Hoba West meteorite in Namibia, which at 60 tonnes + is the largest single meteorite found on Earth and which is also sans crater.

    http://giantcrystals.strahlen.org/africa/hoba.htm

  6. Colin 4

    smashed to bits

    isn't it likely that the actual impactor DID smash to bits, and this is just one of the bits that got thrown clear of the original impact site ?

  7. Stef 4

    @Sleepy3

    Sleepy, quite clearly that is yet more evidence of Big Foot. Obviously the Big Foot tribe of sasquatch built the face of Mars, and NASA are doing another cover-up.

  8. Graham Dawson Silver badge
    Coat

    Footprint eh?

    Well the Hoaglands of this world might zero in on that, but think about it for a moment: a lump of iron soft enough for someone to make a visible footprint in would have to be hot enough to turn that foot to so much chared long pork in the time it took to make the print.

    The one with the blacksmith's apron please.

  9. James 47

    A solution

    This meteor bounced off Earth's atmosphere where it melted a bit, and shot off in the direction of Mars.

  10. Anonymous Coward
    Coat

    Re: Question or two

    Good questions, but there's no mistery. Even weighing half a ton may not cause a significant crater if the atmosphere they're hinting at was thick enough. But more importantly, any crater would have been small (being metallic and whole, it didn't explode on impact so no major hole) and easy for the Martian weather to erode. The rock lies exposed because over long periods of time erosion would have removed the surrounding softer rock, and left the much tougher metal behind. It is also possible that flowing water may have moved the meteorite from its original impact site to where it sits today.

    This is not the first meteorite that the rovers have found. There was a smaller one - also metallic - found a few years back near one of the landing sites, and quite near a heat shield that had been shed.

  11. Your alien overlord - fear me

    Or

    this is just a fragment of the real meteor which hit, vapourising Martian-kind and itself 50 million years ago. Bit's flew off the low density planet and smahed into ours.

    And we all know what happened 50 million years ago....

  12. Mike Bell
    Grenade

    @Steve Swann

    That's the point... a thick atmosphere would slow the bugger down to a few hundred km/h. It could have easily skipped and bumped along the surface if it came in shallow. The evidence from that would soon be wiped out by the Martian sands.

  13. Winkypop Silver badge
    Alien

    Face of the Madonna

    If you look very closely you can see the face of the Madonna !!

    ...is there a Martian eBay I wonder?

  14. Paul H

    Different surface?

    Would it not be just as likely that the lack of a crater is due to the surface being significantly different rather than, or as well as, the atmosphere? Could it not have landed on water or ice which has since gone? This would account for a lack of a crater. After all, wasn't the location for the lander's mission chosen due to the high likelihood of it being an area that once had standing water?

    The object looks quite irregular for something that's been slowed significantly by an atmosphere. If it had been slowed enough to not leave a crater, would it not be more rounded and melted?

  15. Stevie

    Bah!

    The whole "meteoric" origin theory is riddled with more holes than the object itself, which is obviously the wadded-up wreckage of the Beagle-2. You can just make out the BS Kit mark on the lower right underside.

  16. Matthew 17

    The is the reason we need to go there

    The mysteries of that rock would be solved in a tiny fraction of the time it'll take that robot, if an astronaut paid a visit.

  17. Anonymous Coward
    Anonymous Coward

    Cleaver people or just back seat geeks?

    Its nice to see so many proffesors and other highly qualified scientists here. But i have to wonder why you lot aren´t working for ESA or NASA with your extencive knowlage of space, mars and so on.

  18. asiaseen

    Spirit, remains bogged in a sand trap

    Not going to make the Ryder Cup team this year, then?

  19. Ged T
    Welcome

    People need to be there or...

    ... a we need a rover that can overturn such an object, in order to view the underside...

    Imagine the impact if, overleaf, there were unusual symbols/'alien writings' or even a "This side UP" notice...

  20. Anonymous Coward
    Headmaster

    LMAO@AC

    'Cleavers', 'Proffesors' and 'extencive knowlage'?

    Please tell me you're taking the p*ss...

  21. Anonymous Coward
    Boffin

    @Ghost 1

    Don't forget 'knowlage'

    we dunt need no educashun.

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