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Tuesday, July 22, 2014

When it Comes to Eclipses, Partial is the new Total

     Enjoy this remarkable video of potato-shaped Phobos, the 11.2-km-in-diameter moon of Mars passing in front of the sun taken by the robot Curiosity from the surface of Mars:





    And the image above makes a wonderful Partial Ellipsis/Eclipse of the Sun logo, methinks.

    Phobos is only 6000 km from the surface of Mars so even though it is much smaller than the Earth's moon it appears to eclipse less of the sun and does so in splendid, craggy, Mr. Potato Head detail.

     Keep your eyes on Phobos, though, because it is moving a meter or more closer to Mars every century. In 10-15 million years (though some researchers think it will be longer, up to 50 million years) it will likely be pulled into Mars by its tidal forces and break up to become just another planetary ring. Phobos orbits Mars once every 8 hours.

     This phenomenal, enhanced photo shows clearly the Stickney crater on Phobos:





     This main crater on Phobos was named by Asaph Hall in 1877 for his wife, Chloe Angeline Stickney Hall, a mathematician, abolitionist and suffragist. Note the smaller crater within the larger crater.

      The striations (see below) on Phobos were originally thought to be related to the crashing of the object which created the large Stickney crater. However, these striations are centered on the leading apex of Phobos in its orbit (which is not far from Stickney). Researchers believe that the striations have been excavated by material ejected into space by impacts on the surface of Mars. The striations thus formed as crater chains, and all of them fade away as one moves toward the trailing apex of Phobos.


   
        (There is also some pretty wild stuff out on the interwebs about Phobos being a space station, being formed of sedimentary rock, etc.)

      Phobos, from the Greek word for fear, is likely composed mostly of carbonaceous chondrite (or C chondrite). The carbon content is likely to be quite low, however, perhaps less than 2 percent:





      Robert Krulwich describes the Phobos partial eclipse well in today's NPR blog (and is credited for today's blog title--it was too perfect for Partial Ellipsis of the Sun to pass up). His description is spot on:


 When it Comes to Eclipses, Partial is the new Total

Enjoy!

Steph

(Word Woman)



This display at the Denver Public Library titled "I don't remember the title but the cover was green" made me smile.



 



40 comments:

  1. The photos of Phobos (be sure to see the 6x enlargement) were taken on August 20, 2013.

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  2. Phobos eclipses less of the sun than the Earth's moon does, not more. Like, totally.

    ReplyDelete
    Replies
    1. Righto. All fixed. Less is the new more.

      Delete
  3. When you attach documents to your email do you use eclipse?

    ReplyDelete
    Replies
    1. ... and do you S.W.A.K. your emails with your ellipse?

      Delete
    2. I do. Set that one up nicely ;-).

      The ellipse has become a tad too prevalent in my writing of late. I am working on it . . .

      Delete
    3. Before you start working on your ellipses, perhaps you should consult a philosopher of punctuation. Three dots “suggests an infinitude of thoughts and associations.”

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    4. Quite timely, jan. Though I suppose it could be a good thing at times and not so good at others to "suggest an infinitude of thoughts and associations." I'd like that job though, "Philosopher of Punctuation!';:. . ."

      The Chicago Manual of Style recommends . . . not ... I agree. The . . .fits better with infinitude.

      Here's my question: Is the Elliptical trainer name solely related to an elliptical "orbit" or it somehow related to . . . as well?

      Delete
  4. I am now getting ads for a wireless metal detector to find gold nuggets and Great Basin meteorites.

    ReplyDelete
  5. Is your Mr. Potato Head reference a comment on the shape of Phobos, or on the googly-eye appearance of the eclipse pix?

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  6. Both. Google-eye, jan ;-)

    Google could use those googly eyes in their logo too.

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  7. Speaking of Mars and geology (areology?), here are 2 new products from USGS, a geological map of Mars, and a rotating globe of Mars geology. Enjoy!

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  8. Thanks, jan. I was struck by how parts of the areologic map and the first part of the rotating globe look familiar. Plate tectonic-y.

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    Replies
    1. I just read the full New York Times article on Mars. Amazing we are still so fascinated by early Mars history and H2O.

      http://mobile.nytimes.com/2014/07/23/science/space/brand-new-look-at-the-face-of-mars.html?_r=0&referrer=

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  9. I guess that stuff you mentioned about Phobos being a space station derives from a theory promoted in 1958 by I.S. Shklovsky (Carl Sagan's co-author -- see my comment in last week's blog), who interpreted the moon's decaying orbit to imply that it was hollow and very light: "one calculation yielded a hollow iron sphere 16 kilometers (9.9 mi) across but less than 6 cm thick." He neglected to consider tidal effects.

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    Replies
    1. Pretty wild how small the world is getting. I knew the name Shklovsky was familiar.

      Do you think Martian space stations could be out there?

      Delete
  10. I'd like to point to a few other great partial eclipse photos, by Thierry Legault:

    Eclipse of the Sun by the Moon and the ISS

    By the Shuttle Atlantis and the ISS

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    Replies
    1. Wow. Quite extraordinary images.

      I've seen Thierry Legault's work before and enjoyed it.

      Delete
  11. Steph, jan, et. al.,

    Sorry I'm late to the party. Had some wi-fi access issues.

    Steph,

    Your latest PEOTS logo is very… eccentric.

    Speaking of eccentric, at my local library all books don green dust jackets each March 17. Then they check out of the library and paint the town green, all the while imbiblio-ing green beer.

    People who subscribe to Netflix know that “Orange Is the New Black.” But people like me, who are members of the Minnesota Fruit Growers Association (MFGA), know that “green is the new orange.”

    Only the older oranges are orange… although, I guess, really old oranges might be green.

    LegOJ

    ReplyDelete
    Replies
    1. Lego, glad you are back on line.

      Eccentric as in orbit or eccentric as in odd?

      Do the books really don green dust jackets at your library...or were you setting up that clever imbiblioing line?

      Not many oranges/greens growing in MN either?

      Word Questioning Things Woman

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    2. WQTW,

      Eccentric as in googly-eyed. Not odd. But it is like they copied your logo!

      The secret of life is “setting up.” Setting up yourself (if you’re a Legomaniac like me), others (if you are generous), or your treasure in heaven (if you are a believer.) If you do enough #2, #3 will take care of itself. (If I were a library director, I truly would have all green dust jackets put on books on 3/17, then would file for unemployment insurance the following day.)

      The Gopher States boasts greens, but the only orange ones are not of the golden-sectioned variety but of the 20-carrot-gold variety.

      LegoSaltGrainsRequired

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    3. I think I've got it, Lego. Thanks for carrotifying.

      Word NaCl cubes/"grains" taken Woman

      Delete
    4. From the Latin "cum grano salis" an antidote to poison. . .

      Grain as a unit of measurement, not shape.

      Take this, too, with a grain of salt!

      Delete
  12. Maybe all dinosaurs in the clade had feathers:

    http://www.theguardian.com/science/lost-worlds/2014/jul/24/kulindadromeus-feathers-dinosaur-birds-evolution-siberia-russia

    Exciting stuff!



    ReplyDelete
    Replies
    1. They probably wanted feathers for the same reason I want that PC-12.

      Delete
    2. Probably ;-).

      I read the original abstract--classic case of burying the lead, Lego?

      The opening sentence describes dinosaur feathers in northeast China but the story about the Siberian dinosaur is buried a few sentences in. Burial is good for preservation but not elucidation, methinks:

      http://m.sciencemag.org/content/345/6195/451

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    3. SS,
      Booth and Oswald buried the lead into sitting president. Undertakers had to bury the dead. Journalists who undertake to begin their story with three paragraphs critiquing the merits and demerits of the performance of “Our Favorite Cousin” at Ford’s Theatre buried the lead (also sometimes spelled “lede.”)

      Your are correct about this link being a classic Jurassic case of lead burying.

      I have to admit, however, that I did intentionally sometimes bury the lead in newspaper stories I wrote, but never deeper than the second paragraph. I did this, I said, “for dramatic effect.” My editors hated it. My editors were right.

      The movie “Broadcast News,” has a great poignant break-up scene near the end where the character played by Albert Brooks exits with, “I buried the lead.”
      Broad cast News” is in my Top 100 movies list.
      Lego…

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    4. Thanks for your always amusing and interesting take on things, Lego. The "click bait" nature of on-line news sites seems to promote burying the lead to get people to take a look. You were just ahead of your time!

      In the abstract cited above, the chronological nature of the writing leads to some confusion about where the newest discovery is located, IMHO.

      I also enjoyed "Broadcast News" and the Albert Brooks clip, of course.

      And, don't be late to the Tardigrade Party going on right now in this week's Partial Ellipsis of the Sun--hot off the presses, er, electrons.

      Steph

      Delete
  13. Returning to last week's discussion of Pangea, here's a map of the supercontinent, with modern political boundaries imposed. Going back to first principles should make solving the Ukraine/Russia, Israel/Palestine, etc., questions a snap! I'm suspicious, though; the map’s creator is Massimo Pietrobon, which sounds like it should translate as "really big rocks [are] good", or something like that.

    ReplyDelete
    Replies
    1. It does make one think about political boundaries, especially since the "All Land" continent of Pangaea was all one big, happy land mass.

      Well, as to Massimo Pietrobon, really big rocks ARE good. (Small ones, too).

      Delete
  14. The game 2048 is lots of fun, even though I still don't completely understand it. I am to the 1024 level so far. . .

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  15. I've made it to 2048 twice so far; 1024 routinely.
    What is it about that game ?

    ReplyDelete
    Replies
    1. jan recommended it awhile ago but I just took it up this afternoon. That may have been a mistake. . .More positive reinforcement than elbow pads on an English professor's jacket.

      Of course, listening to James Taylor on Prairie Home Companion made it all the more pleasant for my first go.

      Any others you like?

      Delete
    2. Alas, my plug-ins are not working. Will try on a different device later. It looks intriguing . . .(I was able to see the RNA descriptor page.)

      Delete
    3. Alas, the game did not like any of my computing platforms. . .

      Delete
  16. Preaching to the choir here but there's some good stuff from PBS News Hour:


    http://www.pbs.org/newshour/making-sense/ask-the-headhunter-whats-the-skill-all-employers-judge-you-on/

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  17. Ever hear of a yogh?

    http://en.m.wikipedia.org/wiki/Yogh

    There must be a pun in there somewhere. . .

    ReplyDelete
    Replies
    1. ... something about eating yak yoghurt in a yurt?
      I'm sure that Dr Seuss
      would have a few choice
      rhymes.

      Delete
    2. Yes,I expect so.

      I also would like ert to be a word to balance out inert.

      Dr. Seuss (got it right that time)
      Could surely, purely, curely,
      Make it Yogh Ert.

      Delete