By Phil Plait | March 5, 2008 8:00 am

I can’t seem to go a week without seeing my friend Dan Durda popping up on TV or someplace. He’s an astronomer, currently on loan to NASA, and he specializes in asteroids. For quite some time he has looked for a class of asteroids called Vulcanoids, a group of rocks that orbit the Sun inside Mercury’s orbit. It’s not known if these things even exist, but if they do they’ll be very interesting. That close to the Sun, all the lighter molecules like water will have burned off, leaving any Vulcanoid rich in metals.

Dan is interviewed (along with other astronomers) in this short clip on MSNBC’s website (I had some trouble embedding this, so if it doesn’t work, try the direct link).

On a related note, my e-friend Bill Arnett runs the Nine Eight Planets website, and he has a short but cool writeup on the mythical inter-Mercurial planet Vulcan. I think historical stories about wild goose chases like that are really fun to read about.

CATEGORIZED UNDER: Astronomy, Cool stuff, NASA, Science

Comments (13)

  1. The eight planets page credits the text to Paul Schlyter and not to Bill.

  2. Bill runs the site, and others have contributed.

  3. It’s obvious to anyone that this inter-Mercurial planet is real and has been known since the time of the Mayans. Modern scientists are just covering it up because they know the population won’t be able to deal with the untold destruction come 2012 when Vulcan’s orbit intersects with earth and it rains fiery planetary destruction on us.

  4. As a non-scientist I must admit I get a bit of a chuckle out of the idea of specializing in something that may or may not exist. At least he specializes in something with a cool name.

  5. andy

    Given that a large number of extrasolar planetary systems apparently have planets much closer to the star than Mercury is to our own Sun (right down to a few Roche radii in some cases), it is curious that the same region in our solar system doesn’t seem to contain anything.

  6. silence

    andy: A big chunk of the reason that we’re detecting planets which are very close to the star they orbit is that the techniques we’re using for identifying extrasolar planetary systems find it much easier to detect planets close to the star. In particular, a planet close to the star causes the star to wobble by a much larger amount than a planet of the same mass much further from the star. More massive planets are, for the same reason, also easier to detect.

    There is a fairly large chance that the planetary systems we’ve been able to identify are not at all typical of planetary systems.

  7. Brian

    Does anyone else remember the Asimov science essay where he discussed Vulcan, and then “demonstrated” that the ancient Greeks not only knew about the inter-Mercurial planet, but also knew that its existence would eventually be disproved and how?

    It went something like this: According to Greek mythology, Cronus knew of a prophecy that he would be destroyed by his own son, so whenever Rhea gave birth he would swallow the child. But when Zeus was born, Rhea hid Zeus and gave Cronus a sack with a stone in it instead. (And indeed Zeus did grow up to defeat Cronus.) One of Zeus’s many acts, mentioned in the Iliad, was to threw Hephaestus down from Mount Olympus, as a punishment.

    But Hephaestus is just the Greek name for the Roman god Vulcan. And so we see, he was indeed eventually thrown down from the heavens. And by who? None other than the man indentified as one stone, or in his own native language, “ein Stein”.

  8. andy

    silence: I’m aware of the detection bias, but that isn’t the issue I was referring to.

    The issue is this: it would seem that planets form in a way that fits the largest number of planets possible into the system (indeed, this theory has successfully predicted the existence of planets at the location of 55 Cancri f and HD 74156 d). This leaves open the question of why the innermost planet is not packed in right up against the star, especially given the variety of inward migration processes available. Having a large stable region which could be occupied by planets/asteroids but isn’t is somewhat troubling under this model and perhaps warrants explanation.

  9. Jim

    Vulcanoids are not the only thing that Dad Durda is interested in and while none have yet been found, there’s good reason for that – they don’t get far enough from the Sun as seen from Earth to be visible in a dark sky like the rest of the asteroids we have found. Even the Aten type near-Earth asteroids (which orbit mostly within the orbit of Earth but have aphelia outside of Earth’s orbit and semi-major axis less than Earths) get to 1 AU occasionally where we can see them. But Vulcanoids would have aphelia less than 1 AU and would never get more than 90 degrees from the sun even if they were borderline Aten asteroids. Must presumably have aphelia significantly less than 1 AU and therefore don’t get more than a few 10s of degrees from the Sun. Dan has done some great work which has included flights in FA-18 aircraft (lucky duck!) with cockpit mounted cameras and I wouldn’t be surprised if he hitched a ride on some spacecraft someday with such a camera. BTW, amongst Dan’s interests are asteroid collisions, asteroid moons, asteroid impacts and he’s also an accomplished space artist as well as a pilot and a cave diver and a good buddy of mine as well as the BAs.

  10. Vulcan is inside the orbit of Mercury? Not surprising. It was extablished in “Amok Time” that Vulcan’s climate is much warmer than Earth’s. Good thing Mr. Spock only gois into heat once every seven years.

  11. Lyle G

    Er…Vulcanoids don’t have pointy ears?

  12. StevoR

    Sayeth # Lugosi on 06 Mar 2008 at 11:44 am :

    “Vulcan is inside the orbit of Mercury? Not surprising. It was extablished in “Amok Time” that Vulcan’s climate is much warmer than Earth’s. Good thing Mr. Spock only gois into heat once every seven years.”

    But seven years would come around a *lot* quicker if your “year” is just … oh, three days or so!

    So Spock must be in heat every month or less!! ;-)

    Incidentally, if our Sun had a Hot Jupiter type planet in a 2 or so day orbit – would we be able to see it???

    &, if so, what would it look like? (From Earth – & after all I gather even Mercury with its 88 (?) day orbit is hard to see, & Copernicus apparently never saw it ..)

  13. StevoR

    & .. umm .. Wasn’t Vulcan supposed to orbit either Tau Ceti or Epsilon Eridani? Can any Trekkies out there tell me?


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