Highest res images of Iapetus yet!

By Phil Plait | September 10, 2007 6:46 pm

and Emily’s got ’em.

Very cool stuff, and her comment about crater chains is interesting; I see them too and like her I question their reality. But the more we learn about this weird little moon the better; the walnut crest around the equator is totally excellent and I’d like to see more data come in so a better explanation (or a more refined one) can come along.

CATEGORIZED UNDER: Astronomy, Cool stuff, NASA

Comments (19)

  1. folcrom

    No doubt Hoagland will claim the “crater chains” are evidence of an ancient “nuclear bombardment” or some other equally stange drivel.


  2. Dan

    Let’s just get this out of the way, okay?

    That’s no moon. It’s a space station. The crater chain is the result of a failed rebel attack. Haven’t you been paying attention on this stuff? Sheesh.. There was even a great documentary about something having to do with some sort of war up there in the stars.

    Those are awesome pictures though. And, I really can’t see the chain o’ craters in the enlarged version of the photo, so I’m thinking it’s an illusion as well.

  3. Bunsen

    Hoagland may make those claims, but fortunately he just doesn’t update his psychotic website as much as he used to anymore. It could take him a whole three days to jump all over this with some inane theory.

  4. Keith Harwood

    I was right, it is a mould mark. They forgot to grind it off after Iapetus was made. You can even see where the parting compound was put on too thick and ran to near the edge. Shoddy workmanship I call it. What was it, Friday afternoon or something? In my day when people made a moon they made it properly.

  5. MaDeR

    Why they misspell Gilese 581c? They wrote “Gieise”… not good, not good.

  6. MaDeR

    Damn, and of course I mispell it myself… Gliese! GLIESE!

  7. Grand Lunar

    Not only that MaDer, but you also puit it in the wrong blog entry. It’s in the one previous to this.

    I wonder what Arthur C Clarke would think, in regards to the novel ‘2001’, which, unlike the film, involved Iapetus.

    Very cool to already see some dramatic, and facinating, images of this mysterious moon.

    I recall reading that Cassini will no longer be in favorable positions to image Iapetus after this. Is this true?

  8. I wrote a spoof article about the Iapetus ridge shortly after it was dicovered – see http://www.herring.pwp.blueyonder.co.uk/Space/Headlines.htm (Earth Probe Close to Discovering Vast Secret)

    Note – not to be taken seriously!

  9. Depends on what you regard as favorable opportunity. This is the only close flyby planned for primary as well as extended mission. I think I read somewhere there actually won’t be any imaging coverage of Iapetus after this flyby. A rather bleak prospect, but an understandable one if you think about the distances involved.

  10. peptron

    [homer]Mmm… walnut…[/homer]

  11. Tom

    Wow! Another amazing shot from Cassini. I have another 2 monitor wide wallpaper for my Ubuntu machine. :-)

  12. KaiYeves

    Huh? I thought Clarke was alive.
    I never thought I’d say this, but don’t be hard on Hoagy.
    At least wait until tomorow.
    Today is, after all, a day for compassion.
    And Cassini rocks my socks any day of the week.

  13. Troy

    That belly band would be great for a moon sized game of “Capture the Flag”.

  14. Keith Harwood

    It’s a cannon ball! Last night the ABC (Australian Broadcasting Commission) showed an episode of TimeTeam where, among other things, they showed the casting of a cannon ball. It was identical to Iapetus. Mold mark and all. Mind you, it wasn’t as big, but when you have only three days to do it in, you can’t get too ambitious.

  15. Hoagland:

    However, that this geometry is not some new form of internal geological control — modulated by the planetary Hyperdimensional Physics we’ve found operating on other planets – also seems clear; neither “ring” lies anywhere near the infamous 19.5-degree “upwelling latitude” controlled by internal “tetrahedral” forces we see operating on other planets and their satellites. Yet, the placement of both “ring features,” 120 degrees apart, is obviously conveying the same “tetrahedral message” left behind in other artificial ruins we’ve explored across the solar system ….

    Crap. I totally missed that in Science. Something that big, you’d think CNN would have said something.

    Darn mainstream media. Just can’t trust ’em fer nuthin’.


  16. Regner Trampedach

    Re: Crater chains.
    If we assume a case similar to the Shoemaker-Levy impact with Jupiter, we can calculate the distance between craters on Iapetus. We start off by making some
    simplifying assumptions and afterward test whether they change the conclusion.
    a) Both Jupiter and Iapetus are stationary in their orbit while getting pummeled.
    They still rotate, though. b) the impact occurs with zero impact parameter (head-on collision).
    According to tables found on the web, the average time between impacts of the
    last 10 fragments was about 5 hours. In that time the equator
    of the 718km radius Iapetus, rotating once every 79hours, has travelled about
    12km or 1.7% of the radius of Iapetus. This is actually not too far from what is
    seen in the images. Considering that the fragment train of Shoemaker-Levy
    lengthened by a factor of 10 in a year, there is ample room for factors of 10 (up or
    down) in my result above. With impact close to the limb, the distance between the
    craters would be larger.
    Can we ignore the orbital velocities (one of my assumptions): From the length
    of the 23 fragment train around time of impact, 5,000,000km, and the 5hours
    between impacts, I get an approximate relative velocity of 45,000km/h, compared to the
    1,900km/h orbital velocity of Iapetus. Jupiter and Saturn have orbital velocities
    of 47,000 and 35,000km/h, respectively, which means they can’t be ignored. On
    the other hand first assumption would be that they are randomly oriented with
    respect to the impactor, in which case you would just get a larger spread in the
    result above – and, of course, many cases where many or most fragments would
    miss the “target”.
    Thanks for a great post, Phil & Emily.
    Cheers, Regner

  17. KaiYeves

    Great pictures. I’d love to meet Emily. Sorry if I was a little harsh back there, but ad hom is just a fancy word for name-calling, and I’ve been called a few too many names in this life.

  18. j

    Fantastic shots; thanks for pointing to this!

  19. Spikey

    It’s always amusing to me just how fast and rabid the disinfo agents jump on any otherworldly information, regardless of where it is or what it is.

    Just a bit of advice to ‘real’ members of the public.

    Make up your own minds, use your brain and seek out your own data. Do not be swayed one way or the other and this or any other subject.

    The one’s who shout the loudest, often have the most to hide. Well, their ’employers and masters’ do at least.

    Read all you can, look with a critical eye.



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