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Space Science

Earth Acquires a Quasi-Moon 258

richard_za writes "Earth has acquired a so called quasi-moon, an asteroid: 2003 YN1, which will encircle us for the next couple of years while it orbits the sun on a horse-shoe shaped path. Full story on News24. It was found by team led by Paul Chodas, an asteroid specialist at Nasa's Jet Propulsion Laboratory in California. An orbit simulation can be seen in this Java applet."
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Earth Acquires a Quasi-Moon

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  • no reg link... (Score:5, Informative)

    by sweeney37 ( 325921 ) * <mikesweeney@gmai[ ]om ['l.c' in gap]> on Saturday March 27, 2004 @11:38AM (#8688914) Homepage Journal
    Here's a link to Discovery Channel's coverage [] without the need for registration.

  • by OverlordQ ( 264228 ) on Saturday March 27, 2004 @11:38AM (#8688917) Journal
    "That's no Moon!"
  • by Metallic Matty ( 579124 ) on Saturday March 27, 2004 @11:39AM (#8688927)
    ... which will encircle us for the next couple of ears...

    I'm unfamiliar with this unit of measurement.
  • by Stevyn ( 691306 ) on Saturday March 27, 2004 @11:40AM (#8688931)
    Have you no remorse? It's one thing to slashdot a web page, but java? You can't rightly do that!

    Yeah I know, it's a joke. The class is just like any other static file.
  • by Pollux ( 102520 ) <speter&tedata,net,eg> on Saturday March 27, 2004 @11:41AM (#8688937) Journal
    Earth has acquired a so called quasi-moon, an asteroid: 2003 YN1, which will encircle us for the next couple of ears .

    And exactly whose ears are we going to sacrifice to the asteroid god in order to have it here in our presence?
  • So it's not a threat (Score:5, Interesting)

    by Space cowboy ( 13680 ) * on Saturday March 27, 2004 @11:41AM (#8688939) Journal
    Despite the warnings about only 2-body maths being used in the applet, it's too tempting not to run it forwards and backwards a bit just to see... It turns out the closest approach would have been roughly a week before it was noticed on Dec 8th 2003, at 0.0455 AU or ~6,807,000 km. A fair old distance :-)

    I guess it's not too often you get your own asteroid orbiting, but this is still going to be a looong way away for a lot of the time. Maybe when it does get close though, we can send something up to it - beats the hell out of going out to the Oort cloud, even if you do find a few planets along the way :-)

  • I wonder... (Score:4, Interesting)

    by TexasDex ( 709519 ) on Saturday March 27, 2004 @11:41AM (#8688942) Homepage
    What sort of eclipse can we expect from this? To experience a solar eclipse from a temporary sattelite would be a once-in-a-lifetime experience.
    • Re:I wonder... (Score:3, Interesting)

      by raymo03 ( 737701 )
      I don't think it would even be possible to have an eclipse caused by such a (relatively) small object at that great a distance.
    • by G4from128k ( 686170 ) on Saturday March 27, 2004 @12:01PM (#8689047)
      There is an entire branch of astronomy that uses distributed observations to map the size and shapes of asteroids using occultations (eclipses with distant stars). When an asteroid passes in front a distant star, the star winks out and then reappears. Knowing the duration (start and stop times) of the occultation, the location of the observer, and the orbits of the Erath and asteroid lets people estimate the size and shape of the asteroid. International Occultation and Timing Association [] collects data from telescopes around the world (many in the hands of hobbyists) and uses the data to make these estimates.
    • Re:I wonder... (Score:5, Informative)

      by tverbeek ( 457094 ) on Saturday March 27, 2004 @12:21PM (#8689142) Homepage
      What sort of eclipse can we expect from this?

      The kind that you wouldn't be able to detect (except maybe by careful monitoring of the sun with a well-filtered telescope pointed at exactly the right spot). Imagine something much smaller than the moon and even farther away passing in front of the sun. That's what this is.

      To experience a solar eclipse from a temporary sattelite would be a once-in-a-lifetime experience.

      If it were noticeable. But temporary satellites (like the ISS) cast (highly-attenuated) shadows on the Earth every day.

    • What sort of eclipse can we expect from this? To experience a solar eclipse from a temporary sattelite would be a once-in-a-lifetime experience.

      Given that it's only about 100 meters in diameter, seeing its eclipse would truly would a once-in-a-lifetime experience; in fact, your last experience. That's becuase to see a noticeable shadow you would have to be within a few kilometers of the asteroid. That would mean that it would be within a few milliseconds of impacting with multimegaton force in your gene

  • by hot_Karls_bad_cavern ( 759797 ) on Saturday March 27, 2004 @11:42AM (#8688947) Journal
    Here's the screenshot:

    O o .
    Sun:earth:new "moon"

    Not to scale. All rights reserved.
  • "Our" moon? (Score:5, Insightful)

    by Anonymous Coward on Saturday March 27, 2004 @11:45AM (#8688966)

    If it's orbiting the sun, then how can it be called "our" moon? Just because it's vaguely in our vicinity?

  • Isn't it Cruithne??? (Score:4, Informative)

    by Pig Hogger ( 10379 ) <> on Saturday March 27, 2004 @11:48AM (#8688978) Journal
    Doesn't the Earth already has a second moon, Cruithne []???

    And this is a dupe from 4 years ago.

    Earth's Second Moon [] 2nd Moon Orbiting Earth Discovered []

    • by Geoffreyerffoeg ( 729040 ) on Saturday March 27, 2004 @11:55AM (#8689014)
      According to the Discovery Channel article linked elsewhere, 2003 YN17 is at least the fourth moon. The three others are the real moon (Luna, as some call it), Cruithne, and 2002 AA29.

      Have the other two left already/have there been others in the past?
      • by Pooua ( 265915 ) on Saturday March 27, 2004 @02:55PM (#8690026) Homepage
        Have the other two left already

        No, Cruithne is projected to be in our neighborhood for thousands of years.

        "Earth has a second moon, of sorts, and could have many others, according to three astronomers who did calculations to describe orbital motions at gravitational balance points in space that temporarily pull asteroids into bizarre orbits near our planet.

        "The 3-mile-wide (5-km) satellite, which takes 770 years to complete a horseshoe-shaped orbit around Earth, is called Cruithne and will remain in a suspended state around Earth for at least 5,000 years." More Moons Around Earth? It's Not So Loony []

  • by da3dAlus ( 20553 ) <dustin,grau&gmail,com> on Saturday March 27, 2004 @11:48AM (#8688980) Homepage Journal
    Not even a little evil?
    The Diet Coke of evil?
  • Ears? (Score:4, Funny)

    by payndz ( 589033 ) on Saturday March 27, 2004 @11:48AM (#8688984)
    Would those be the final front-ears?
  • since 1996? (Score:2, Interesting)

    "Since 1996, its path has taken it round the earth, making it a quasi-satellite. This phase will last until 2006," the report said.
    if it's been in orbit since 1996, why has it only just been found? I'm quite curious
    • Re:since 1996? (Score:2, Insightful)

      by KD5YPT ( 714783 )
      Space is big, asteroid is tiny compare to space. Plus with all those space junk up there, it's literally looking for a grain of pepper in a sea of salt.
      • " it's literally looking for a grain of pepper in a sea of salt." You can't use the word "literally" when refering to an analogy... it's complete nonsense.
        • by Golias ( 176380 )
          But he meant it literally. If astronomers weren't so damn busy sifting through the salt on their dinner table for that grain of pepper, they probably would have spotted the asteroid sooner. :)
    • if it's been in orbit since 1996, why has it only just been found?
      (Well, it isn't really 'in orbit'. If it were, it would stay that way indefinitely, not 'leave orbit' 10 years later.)

      Because it's really small. It was discovered when it was very close to its point of closest approach to the Earth. Since that time, it's been tracked well enough that it's possible to project that path into the future and the past to arrive at the 10-year 'phase' statement.

    • if it's been in orbit since 1996, why has it only just been found?

      Because it doesn't actually spend much time around Earth. It's really orbiting the sun in a path that coincides with ours. When it nears the Earth, our gravity grabs it, swings it around, and sends it back around the sun in the opposite direction.
  • Horseshoe? (Score:5, Funny)

    by Anonymous Coward on Saturday March 27, 2004 @11:53AM (#8689005)
    "..while it orbits the sun on a horse-shoe shaped path..."

    If only Isac Newton knew this...
    • No kidding (Score:2, Funny)

      by Anonymous Coward
      If a horse had dropped on him we wouldn't have to take calculus classes...
    • Re:Horseshoe? (Score:2, Informative)

      by Guppy06 ( 410832 )
      Nah, he'd still be scratching his head at the whole "precession of Mercury" thing.
  • by Anonymous Coward
    he'll know what to do
  • by StupendousMan ( 69768 ) on Saturday March 27, 2004 @12:02PM (#8689055) Homepage

    This is the third asteroid we've found which has an orbit tied loosely to that of the Earth. The others are 3753 Cruithne and 2002 AA29. You can see pictures and applets and read about these other bodies at Paul Wiegert's web site: []

    • Well, maybe, but calling these asteroids moons of Earth is basically silly. This new one has an orbit that goes out past Mars, and merely passes within a few million km of the Earth's orbit at one point. Cruithne's orbit extends from about Mars' orbit into near Mercury's orbit, and doesn't ever really get close to Earth. Both of these orbits are significantly inclined to the ecliptic.

      Suggesting that they are somehow related to Earth is basically a sign that the writers are utterly clueless. Next we're
  • uh wha'zat? (Score:5, Interesting)

    by aztektum ( 170569 ) on Saturday March 27, 2004 @12:06PM (#8689074)
    " orbits the sun on a horse-shoe shaped path."

    It sticks itself in reverse to avoid making a complete loop.

    But how can this be a moon of Earth if it orbits THE SUN?
  • Let's NAME it!! (Score:2, Interesting)

    by neBelcnU ( 663059 )
    I wanted to call it "George" but the teenager in the house has christened it "Foof." (Two o's, like "moon". Her 1st draft was naturally scatological.) C'mon /.ers, let's come up with a name!
  • by utlemming ( 654269 ) on Saturday March 27, 2004 @12:16PM (#8689115) Homepage
    Let's name it Wormwood! Give the religious folk a hell of a time.
  • by DangerSteel ( 749051 ) on Saturday March 27, 2004 @12:24PM (#8689157)
    Let me go find that quatrain. I'm sure there was something about millions dead and nuclear winter and slashdotting the original site...

  • Aussie: That ain't a planet, this IS a planet.
    Bart: That no planet, thats a quasi moon.
    Aussie: Alright alright, I see you've played planetry quasi moony before then.
  • by DrugCheese ( 266151 ) on Saturday March 27, 2004 @12:45PM (#8689241)
    Orbit diagram page temporarily unavailable due to high server load.


    Orbit diagram page temporarily unavailable due to

    Can't we all just take turns?
  • by hustin ( 684493 ) on Saturday March 27, 2004 @12:49PM (#8689262)

    Two drunks are walking along. One drunk says to the other, "What a beautiful night, look at the moon." The other drunk stops and looks at his drunk friend. "You're wrong, that's not the moon, that's the sun." They began to argue when they come upon another drunk. They asked, "Sir, could you please help settle our argument? Tell us what that thing is up in the sky that's shining. Is it the moon or the sun?" The third drunk looked at the sky and said, "Sorry, I don't live around here."

  • With the discovery of this new moon, I'm offering you the opportunity to get in on the action! Just like the original moon, you can now own your own section [] of the new moon.
  • by constantnormal ( 512494 ) on Saturday March 27, 2004 @01:09PM (#8689369)
    What I want to know, is why isn't anyone pushing to steer these NEO rocks into one of the Lagrange points [ grange.html] and construct a REAL space habitat instead of sending a man to Mars or establishing a "permanent" lunar base? It would be pretty cheap to do so, as the technology to build robots to do the grunt work is pretty much within our grasp now. Having sufficient bulk would make for a decent radiation shield, and even a micro-gravity environment is preferable to the zero-G of the ISS, as dust+debris are more readily managed.

    There are at least 3 known small (a few kilometers in diameter) rocks that are close enough to send out a robot "tug" with a large amount of propellant, some good-sized solar arrays (or a nuclear battery) to power an ion drive. All the tug needs to do is match orbits with the asteroid, position itself, make contact and gently push it in the right direction. It would take a long time to put the asteroid into one of the L4/L5 points, but as tugs expire, new ones can be sent (or send additional tugs to speed up the process) at a very minimal cost, with a very simple trade-off of time vs money.

    I would expect that by the time we get multiple asteroids in close proximity to each other in one of the stable Lagrange points, we would be able to send much more capable robotic workers to either tie the asteroids together with titanium I-beams, or better yet, tether them together with carbon fiber cables and put some spin on the assemblage to keep them under tension. Initially, we could construct living spaces inside the rocks, but as capabilities increase, and more material is placed into the mix, it would be possible to create a poor man's RingWorld with considerable acreage. It's a great place to harvest solar power, base elaborate interplanetary communications facilities and astronomical observatories.

    The costs of maintaining an effort like this are very small, and it has the benefit of collecting wandering rocks that might one day drop in on us and put them to good use. Far better than programs to blow them up with nukes, and Bruce Willis won't be around to save us forever.
    • The Earth L4 and L5 points are awfully far out and probably already full of samll space debris, making them dangerous to be in. The lunar L4 and L5, however would be ideal. Having a permanent refuelling base at the L points would be quite ideal. It turns out that L1 and 2 points of most of the solar system are at almost identical potential energy. I'm not certain if this also applies to the L4 and 5 points, though. Try Googling for Interplanetary Superhighway.
    • Sure, that sounds good...

      Until COBRA COMMANDER hijacks the asteroid base and holds the entire EARTH for ransom!

      Betcha hadn't thought of THAT, had you?

    • "easy" is relative (Score:4, Insightful)

      by hak1du ( 761835 ) on Saturday March 27, 2004 @04:27PM (#8690519) Journal
      We seem to be having trouble & high failure rates with just sending tiny robotic probes to Mars, and we can hardly even keep a couple of rusty buckets in low earth orbit operating. Moving a small asteroid gently (maybe using solar sails) should be well within our technological capabilities, but it doesn't seem like we have our act together enough to do it.

      Right now, the US, one of the richest nations, doesn't even seem to be able to pay for health care or secondary education, but we are willing to pay hundreds of billions to have our shoes x-rayed in order to guard against an infinitesimal chance of getting killed by terrorists. So, you see, the problems aren't technical, they are psychological, social, and political.

      (Besides, you really don't want the "oh, that was kilometers" kinds of errors with such a project.)

    • by Anonymous Coward
      What I want to know, is why isn't anyone pushing to steer these NEO rocks into one of the Lagrange points?

      Because it's a stupid idea. A 1-km asteroid weighs a few trillion kg. If you get your rocket data from NASA rather than Niven, you can run numbers on your idea instead of saying 'it's simple' out of your ass. If a VASIMR [] drive can hypothetically get 20 tonnes to Mars in 40 days, how long does it take to move 10^9 tonnes? Think about it. (Put a few dozen engines up there, be creative. Be optimis

  • by Ephboy ( 761440 ) on Saturday March 27, 2004 @01:26PM (#8689456)
    I was looking at the orbits of Pluto and Neptune on the applet, and noticed that Pluto is shown as inside Neptunes orbit at present and until 2011, but I was under the impression that Pluto was once again the farthest planet, as of 1999 [], and wouldn't pass in again until 2226. So I'm not sure their orbits are correct....
  • You heard it folks. I claimed it. Gonna start moving my belongings up there ASAP.

    P.S. Don't tell bush, but I think there may be oil up there and I would like to avoid invasion for now.

  • by pair-a-noyd ( 594371 ) on Saturday March 27, 2004 @03:33PM (#8690228)
    "while it orbits the sun on a horse-shoe shaped path"

    Uh, wouldn't it be easier to fly an elliptical orbit?
  • IANARS (I Am Not A Rocket Scientist), but from playing with the Java applet, it appears that 2003YN1 is going to come surprisingly close to Earth within the next decade.

    In January of 2007, for instance, the asteroid will be trailing Earth by about 0.5 AU. In November of 2020, Earth will be trailing the asteroid by a hair's breadth (in cosmic terms) of 0.1 AU.

    Now, four light-minutes (or even 0.75 light-minutes) isn't exactly spitting distance, but how often do we have asteroids within such close proximity to Earth, in such convenient orbits? I imagine it would be fairly cheap to launch a probe to match orbits with the asteroid, rendezvous with it and do some science. A return mission in 2020 would be a distinct possibility (if it were useful, which I'm not sure it would be).

    Now, the budgetary and planning requirements for a 2007 mission are probably unmanageable at this late date, especially given NASA's (or ESA's) current budgets. But we've got 16 years to plan for a 2020 mission. What manner of experiments might we be able to devise in the intervening years? What possibilities can you think of?

    1) Establish an unmanned observatory on the asteroid

    2) Land a power source and construct a propulsion system (using a linear accelerator to eject the asteroid's own mass?) and try to change the asteroid's orbit. Depending on the composition of that baby, it might be worth a pretty penny if we could put it into near Earth orbit for mining.

    3) Same as #2, only turn the asteroid into a long-term habitat. Free giant space station, anyone?

    OK, so these ideas are a bit far-fetched, possibly venturing into the realm of science fiction. But dreams have to start somewhere...
  • by waynegoode ( 758645 ) on Saturday March 27, 2004 @04:35PM (#8690552) Homepage

    The simulator link is incorrect. It points to 2004 YN1. The correct link []. For a good view in the simulator, tilt the 3D view to straight down, center on earth and zoom in all the way.

    New Scientist has an interesting article [] in their latest issue.

    For a more technical explanation, read the paper [] presented at the Lunary Planetary Science Conference [] last week.

  • Will our quasi-president announce a quasi-mission to land on this quasi-moon?

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