Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 


Forgot your password?
Close
typodupeerror
×
Space Science

Newly Found Planetoid Possibly Larger than Quaoar 46

Posted by michael from the deep-space-one dept.
I am Jack's username writes "A newly discovered planetoid (Google news cluster) 2004 DW in the Edgeworth-Kuiper belt, where some think objects larger than Pluto exist, may be larger than Quaoar - making it the second largest known trans-Neptunian object and 18th largest object in the solar system."
This discussion has been archived. No new comments can be posted.

Newly Found Planetoid Possibly Larger than Quaoar More

Newly Found Planetoid Possibly Larger than Quaoar

Comments Filter:

  • Quaoar (Score:3, Funny)

    by daeley ( 126313 ) * on Friday February 20, 2004 @02:39PM (#8342230) Homepage
    Continuing the uber-Scrabble theme, I'd like the nominate Zzyzx [wordways.com] as the new name. Sure, it isn't in any way mythological, but it has nice legends attached to it. And it's halfway to Vegas from here, so what more do you want? ;)

    • Re:Quaoar (Score:3, Funny)

      by nagudaku ( 693285 )
      it took them so long to find this ? if they can see the most distant galaxy [slashdot.org] , is it really so hard to see just beyond pluto ?

      • Re:Quaoar (Score:3, Insightful)

        by TwistedGreen ( 80055 )
        Not everyone has a bloody Hubble in their backyard.

        And soon, no one will. :(

      • Re:Quaoar (Score:4, Informative)

        by PhuCknuT ( 1703 ) on Friday February 20, 2004 @02:52PM (#8342405) Homepage
        Yeah, because the most distant galaxies are about 1000000000 (not exact, but you get the point) times larger and brighter than an asteroid 40au from earth. An asteroid or comet only reflects light, so the farther it is from the sun the harder it is to see. A galaxy on the other hand, will have billions of stars, each billions and billions of times brighter than what's reflected from an asteroid.
    • Continuing the uber-Scrabble theme, I'd like the nominate Zzyzx as the new name. Sure, it isn't in any way mythological, but it has nice legends attached to it. And it's halfway to Vegas from here, so what more do you want? ;)

      A few more letters so I can hit the triple word score square: Zzyzzyxx [klov.com]

    • Slashdot User zzyzx [slashdot.org].

  • Question for the astronomers among us... (Score:5, Interesting)

    by Baron_Yam ( 643147 ) on Friday February 20, 2004 @02:44PM (#8342302)
    Given that stars (excluding the Sun) are point sources as far as our current telescopes are concerned, and these KBOs are discs... what are the odds of a KBO eclipsing a given star during a standard observation period?

    Things I don't know: 1) density of KBOs vs stars 2) apparent speed of KBOs relative to the stars beyond them. 3) The average length of time any star is in a field of observation at a major telescope.

    Actually, there's probably a lot more I don't know, that's just what comes to mind at the moment.

    • Re:Question for the astronomers among us... (Score:4, Informative)

      by sdedeo ( 683762 ) on Friday February 20, 2004 @03:27PM (#8342992) Homepage Journal
      I think the numbers are off relative to each other by many orders of magnitude. The real problem is that both KBOs and stars are essentially points. The chance of accidental overlap is vanishingly small. (If you stuck a telescope and watched a field of stars for brightness variations, you would see a lot of other stuff: eclipsing binaries, orbiting planets, etc -- see the OGLE project [astrouw.edu.pl], e.g. They have been recently looking for eclipsing planets, but there are huge numbers of contaminants from plain old binary systems.

      You need some mechanism to "increase" the apparent area of the (in this case KBO.) Unfortunately, KBOs are just small rocks, with not too much interesting going on. (Planets that eclipse their own star are easier to see, because they are fixed in the angle they explore on the sky relative to the star.)

      If you're looking for some kind of "eclipse" effect on the background stars, the best way to increase the effective area of your object is to make it heavy enough that it can gravitationally lens something behind it. The lensing effect increases the angular size of the "sweet spot." See the various MACHO searches [ucsd.edu].

    • Re:Question for the astronomers among us... (Score:4, Informative)

      by CheshireCatCO ( 185193 ) on Friday February 20, 2004 @04:49PM (#8344101) Homepage
      Well, let me address (although not outright answer) the question you actually posted: the chances of a given KBO occulting a given star are pretty small. Particularly if the star doesn't lie close to the ecliptic...

      That said, the odds of a KBO occulting a star or, perhaps better, any KBO occulting any star aren't all that tiny. Pluto occults stars on occasion. That's how we get data on the atmospheric structure, after all. Admittedly, astronomers keenly search for these occultations, but they do happen every few years or so. Now, mind you, Pluto is a big KBO so that it has a much higher probablity of passing in front of a star than most of the others. Recall that it is, in fact, one of the very few KBOs that have been resolved in our images. (I believe that Quaoar, Charon, Varuna, and perhaps one or two others have been. It's because we have not resolved many of these that we don't know the albedoes/sizes of KBOs that well.)

      The next question is why should we look for occultations? Using them as a means to detect KBOs is probably a waste of time. Occultations can give you a profile of the atmosphere which might not be interesting for most KBOs, although a non-detection would at least tell us something about KBOs in general. (i.e. - That they don't have atmospheres. Not that I think people would be generally stunned by this.)
      • Freeman Dyson had floated a proposal that I believe I had seen written up in Sky and Telescope. The idea is that you have a whole field of, say, 10 inch telescopes hooked up to photodetectors and a computer. Yes, the chances of any one telescope seeing an occultation among the stars in its field of view is small, but you use a large number of cheap telescopes.

        While Dyson was more of a mathematical theory person, his claim to fame is in physics, and along the school of "when your ownly tool is a hammer,

    • Ordinary asteroids in the inner solar system sometimes pass in front of weak background stars (occultations), which provides the opportunity to measure their diameters by timing the disappearence and reappearence of the star. Sometimes such occultations even have revealed the asteroid to be binary.
      However, such events are rare, even for close-by asteroids. The angular diameter of far-away Kuiper-Edgeworth objects is so small that they almost never pass in front of a catalogued star.
      -The basic idea is sound,

      • Ordinary asteroids in the inner solar system sometimes pass in front of weak background stars (occultations), which provides the opportunity to measure their diameters by timing the disappearence and reappearence of the star.

        I would think that the star would have to not only be observed at the right moment in time, but would have to be observed at significant magnification. You would need to be able to observe which direction the object was moving (with or oposite the earth's orbit and rotation) and h

    • The answer is: choose a star near the ecliptic plane of the Solar System and watch it carefully. About once per thousand years, a KBO will pass in front of it. This will make it dim out for a little less than a second, on average. This is a good way to look for small KBOs, not the rare big ones like 2004 DW. Seem like a tough job? It gets easier if you can watch many thousands of stars at a time, then you might see a few events per year. This is exactly what will soon be attempted by my friends at the

  • namers (Score:4, Funny)

    by lambent ( 234167 ) on Friday February 20, 2004 @02:51PM (#8342400)
    From the article:

    "After the object is numbered, then the discoverers (that's us) have one decade to propose a name to the Internation Astronomical Union. There are even more rules about the name of the object. 2004 DW, for instance, must be named after an underworld diety because it is in a Pluto-like orbit."

    Okay, everyone ... we have 10 years to come up with a better name than Quaoar. Get to it.
    • Uadjet.

      An Egyptian goddess of the underworld who endows justice and truth. She is pictured as a cobra (occasionally winged or crowned), or as a snake with a womans face. (And yes, I know she's sometimes called "Wadjet" but thats just not as cool as "Uadjet" ;))

      Thats where my vote goes anyways! ;)
    • If they're going to have a whole bunch of rules about the naming conventions of planets, then why don't they just make up a list in advance and each successive planet be named on a first discovered gets named basis?

      I know it's the thrill of geek suspense that drives this naming nonsense, but geeze, it's just a name. Call the rose a stench-blossom and name the planet Fred.

      Yeah... Fred... He was the god of underwear I think...

    • 2004 DW, for instance, must be named after an underworld diety because it is in a Pluto-like orbit.

      I can't imagine that this "rule" could hold. If the Kuyper Belt contains more objects than the Asteroid [atariage.com] Belt, I would think we'd run out of ancient gods of the underworld.

      We might be able to extend the idea by naming trans-Plutonian objects after fallen angels and demons [steliart.com], but I'm afraid some of my fellow Christians -- the ones whose belief system depends on a demonic opponent -- would be seriously troubled
    • we have 10 years to come up with a better name than Quaoar. Get to it

      Hell, pull a half dozzen tiles out of a scrabble bag containing Swahili tiles and you'll get a better name than Quaoar.

      -
    • Well, I myself was hoping for "Yuggoth."

  • Comparing trans-Neptunian objects (Score:3, Interesting)

    by geoswan ( 316494 ) on Friday February 20, 2004 @04:37PM (#8343906) Journal
    The discoverers of this object keep refering to which of these objects are closer than others of them. Well, hold on, they are all in a 3:2 resonance with Neptune, orbiting the sun twice for every three orbits Neptune makes.

    So, is it really all that meaningful to compare them based on their distance from us today? If they all share the same period don't they all have the same, um, I don't know what it would be called... But their kinetic energy per unit mass would all be the same.

    If they all have the same period, then wouldn't their average distance from the Sun be directly proportional to the eccentricity of their orbit?

    • "If they all have the same period, then wouldn't their average distance from the Sun be directly proportional to the eccentricity of their orbit?"

      Mr. Kepler says a big nope. He says that the orbital semi-major axis(call it the average distance from the Sun, although it's not technically a time-averaged distance), a, relates only to the period, p, as a^2=p^3, measureing a in AU and p in years. Eccentricity don't enter into it. (It does enter into the time-averaged distance, although I'm going to go o
  • Contact us

    Aljazeera u.f.o.
    P.O. Box 22300
    New Doha - Qoaoar

    Marketing
    Tel: +974 - 438 2705
    Fax: +974 - 442 6865

    E-mail: et-marketing@aljazeera.net

  • Give him time, he will find a face, some masonic connection, and a new way to raise money....

  • Amateur astronomers discover new comets all of the time. But what is with kuiper belt objects? Short period comets (less than 200 year orbits) comets originate in the Kuiper Belt, located inside and outside of Neptune's and Pluto's orbits like Kuiper belt objects. But comets have very eccentric orbits so they come in interior part of solar system and then they become brighter so amateurs could discover them (the most comets discovered by astronomers amateur at the moment of discovery have apparent magnitud

Slashdot Top Deals

You are in a maze of little twisting passages, all different.

Close