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Space Science

Earth's Little Brother Found 432

loconet writes "The BBC is reporting that astronomers have discovered the first object ever that is in a companion orbit to the Earth. Asteroid 2002 AA29 is only about 100 metres wide and never comes closer than 3.6 million miles to our planet."
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Earth's Little Brother Found

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  • by targo ( 409974 ) <`moc.liamtoh' `ta' `t_ograt'> on Monday October 21, 2002 @08:26PM (#4500875) Homepage
    Can't make up your mind of which system to use, huh? :)
    • by Anonymous Coward on Monday October 21, 2002 @08:44PM (#4500989)
      NASA had the same problem... it only cost them $125 million.
    • by bongholio ( 609944 ) on Monday October 21, 2002 @08:54PM (#4501047)
      You think that's bad? As a student pilot, I've learned that the aviation industry has the biggest problem with unit consistency. Or maybe it's the weather industry... check out a _standard_ weather report...

      KGTU 220115Z AUTO 15005KT 10SM OVC005 17/16 A3000 RMK AO1

      here's what it all means:
      kgtu = georgetown, tx airport
      22nd of Oct, 0115Z, automated report
      winds 150deg @ 5 KNOTS
      visibility 10 STATUTE MILES
      clouds overcast at 500 FEET
      temperture 17deg CELCIUS, dewpoint 16deg CELCIUS
      pressure 30.00 INCHES OF HG
      remarks: A01=cannot distinguish liquid from frozen precip...

      Anyways, as you just saw, the weather is reported using KNOTS, STATUTE MILES, FEET, CELCIUS, IN of HG. Damn! 3 painfully different systems of measurement.. and it seems the more i learn, the more stuff like this I see... I really wish us stubborn americans would just switch to SI...
      • I military aviation, we have all of that you mention plus, on the topographical maps, the horozontal distance is in kilometers (metric) and the vertical distance/elevation is in feet! The good thing is the altimiter is in feet too, but still...
      • by bobdotorg ( 598873 ) on Monday October 21, 2002 @10:58PM (#4501625)
        I really wish us stubborn americans would just switch to SI...

        So what are the S.I. units for a good ol' /.'ing?


        Sysadmin pagings?

        Attempted GB's of transfer?

        I'm just imagining what the local newscast tease would sound like, "Scientists at Caltech are reporting a slashdotting of 7.4 on the POSA* scale, centered under Film at 11."

        POSA - Pissed Off SysAdmin
        • "Scientists at Caltech are reporting a slashdotting of 7.4 on the POSA* scale, centered under Film at 11."

          "Scientists estimate the site recieved upwards of 4,000 hits in two minutes, or 3,451 hits metric."
      • Re:meters, miles... (Score:3, Interesting)

        by mpe ( 36238 )
        You think that's bad? As a student pilot, I've learned that the aviation industry has the biggest problem with unit consistency.

        There is a series of Discovery channel involving building a light aircraft, one of the first points the presenter made was that the construction involved using strange mixtures of units.
        You also have fuel load on commercial aircraft being measured as a weight, thousands of pounds; whilst dispensed as a volume; either litres, US gallons or imperial gallons depending where the plane fills up. Messing up the cacluations leading to a flight crew having to test the gliding abilities of an airliner over Canada.

        I really wish us stubborn americans would just switch to SI...

        The US signed the "Treaty of the metre" a long time ago, the US Congress explicitally has the power to set weights and measures so it's really a political problem.
      • by EmagGeek ( 574360 ) <[moc.loa] [ta] [hciretg]> on Tuesday October 22, 2002 @06:28AM (#4502891) Journal
        Americans will NEVER switch to SI (much to my dismay).. Here's why:

        • Football players' union would demand a proportional increase in salary for the extra distance
        • Football stadiums are too short to extend to a 100m playing field and still have enough setback behind the end zones to comply with OSHA safety regulations
        • A quarter pounder sounds bigger than an eighth-kilogrammer, and 100g sounds tiny
        • Americans couldn't comprehend reciprocating fuel mileage (Liters/100km rather than mi/gal)
        • Tons of government software would have to be thrown out and/or rewritten for the switch (wait a minute.... they still use FORTRAN77 for stuff)
        • Having unified units throughout the world might be a threat to our national security (who the hell anywhere else knows what an URG is?)
        • Sears couldn't sell a 500 piece socket set, half of which is completely useless
        • What woman would ever admit to wearing a size 32 shoe or having a size 65 waistline? (Although they'd probably love having a size 86 chest or being 168 tall)
        • The Daytona 500 would become the Daytona 804.672, and that number is too big for NASCAR fans to comprehend (it was only recently that they could start having 600 mile races)
        • A Wendy's Triple w/ Everything has 810 caliories, which is bad enough. However it has 3,391,308 joules - try selling the biggie-size on that one!
        • Who wants to pay for gas by the liter? (or shall I say "litre")
        • Americans don't want to have to start mis-spelling (interject) everything, like "colour" and "litre" and "behaviour" etc
        • The mile markers on I-85 in Alabama couldn't be so cool anymore - now they go 1,1,2,3,2,4,3,5,6,4,7,8,5,9, etc....

        and so on, so as you can see, conversion to SI in America wouldn't be worth the trouble...

      • I really wish us stubborn americans would just switch to SI...

        The Carter Administration tried this back in the 1970s. The plan was to gradually ease the U.S. into the metric system; the first step was to put up metric speed limit signs. Patriotic Americans responded warmly by shooting them down. So you could say that the metric system has not caught on very well here, unless you count the increasing popularity of the nine-millimeter bullet. (Paraphrasing Dave Barry.)
    • Just taking in mind the broad slashdot audience ;)
    • by Myco ( 473173 ) on Monday October 21, 2002 @09:38PM (#4501269) Homepage
      Shouldn't be too confusing. Meters are much shorter than miles.

      What? What?

    • Can't make up your mind of which system to use, huh? :)

      A compromise has been made. When it is on the left side of Earth, use English units, and when it is on the right side, use metric units.
    • Back in the mid 80's, NPR had a couple of fun articles about the non-celebration of the hundredth anniversary of the US going metric.

      This needed a bit of explaining, of course. It turns out that the US, like most countries, actually has no legally-required system of measurements. There are laws (or more often, regulations) that specific items must be measured with specific units. But there is no overall requirement that all measurements be in the same "system".

      However, the US government has always had an official standards body. It has had various names and acronyms, such as NBS (National Bureau of Standards) or NIST (National Institute of Standards and Technology). It basically manages the regulations that say "If you use unit U, you must use the official definition of U, which is ...."

      So how did the US "go metric" in the 1880's? Well, what the national standards bureau did then was to revise the official definition of all terms of measurement. They've done this many times. At that time, they decided that the best system in use by scientists and engineers was the "metric" system centered in Paris. There were already copies of the metric units in the US, and they were used for calibration. What was done was to make this official, and publish definitions of all the common units as multiples of the metric units.

      These definitions have mostly continued. Thus, the legal definition of an inch is 0.0254 meters. This is not an approximation. It is exact, because it's the official definition of "inch".

      It occurred to me while listening to the NPR articles that what the US has is what we in the computer field would call an "extended metric system". We have all the metric terms, but we also have a whole lot more. This obviously makes the American system more versatile, right?

      So it's really an example of "embrace and extend."

  • Brother? (Score:2, Funny)

    by fredopalus ( 601353 )
    Since it's not a planet, wouldn't it be more like a cousin than a brother.
  • Damn! (Score:3, Funny)

    by Kierthos ( 225954 ) on Monday October 21, 2002 @08:27PM (#4500882) Homepage
    They found my secret asteroid base! Now I'll have to move it again before I can continue my plans to take over the world!

  • SO WHAT??? (Score:5, Funny)

    by corebreech ( 469871 ) on Monday October 21, 2002 @08:28PM (#4500887) Journal
    Wake me up when Earth's little sister is found, and you've got some decent JPEG's.
  • Only a 'roid? (Score:2, Redundant)

    by Cyno01 ( 573917 )
    Jeez, havn't they found Counter-Earth yet?
    • Please, say you pulled that out of something /besides/ those tacky S&M novels thinly disguised as fantasy/science fiction.

      Of course, maybe /this/ asteroid has the world where the men are all required to do the bidding of the women... with far fewer stupid sci-fi trappings. Then, the news might actually interest me.
    • If counter earth were there it would bash into it. And of course the counter-brother planet would bash into us at the same time. So no bizaro world. Bummer.
  • Earth's second moon (Score:5, Interesting)

    by EggplantMan ( 549708 ) on Monday October 21, 2002 @08:29PM (#4500894) Homepage
    Not only is it co-orbital but it periodically gets trapped in earth's gravitational field to become a second moon:
    General Simon Worden of the United States Space Command described it as a "near Earth object that is close to being trapped by the Earth as a second natural satellite".


    In 550AD, and again in 2600AD and 3880AD, for a while it will become a true satellite of our planet, in effect Earth's second moon, although technically it will remain under the gravitational control of the Sun.

    • I thought we were up to what, four now?
    • Not only is it co-orbital but it periodically gets trapped in earth's gravitational field to become a second moon:

      Okay, I am no astronomer, nor English major, BUT I am confused all the same.

      How can it be "periodically trapped"? Is it like the object orbits Earth a few times and then skips back off through the cosmos?

      What about that business of every bit of matter in the universe exerting gravitational force on every other bit all the time? Is this object magically shielded from earth sometimes, except for when it is "periodically captured" by Earth?

      Am I confusing periodic capture astronomy in the same way I confuse regular physics with quantum physics?

      No, I am not trying to be a wise ass, these terms do not make sense the way they were preseted to me.
      • the orbit is as such that after orbiting earth for awhile, it builds the momentum to escape earth's orbit and fling itself back out and around the sun.

        Interplanetary probes use this method all the time for escaping earth's gravity. After launch, they orbit the earth for awhile building up momentum (this is known as a 'gravity assist') then fling themselves out.

        This is actually a much more common cosmic event than actually capturing something in permanent orbit. Doing that requires careful placement in the case of artificial satellites or just random chance in the case of natural ones.

  • 600 years? (Score:5, Interesting)

    by cybermace5 ( 446439 ) <> on Monday October 21, 2002 @08:33PM (#4500918) Homepage Journal
    They claim it will be temporarily in earth orbit by 2600 AD. And then they go on to speculate on how important that would be to space exploration, possibly becoming the second object visited by astronauts.

    If, in 600 years, we haven't sent astronauts to visit other planets, I have preemptively lost faith in the human race.

    Come on, in 600 years we should have a pretty decent Mars colony going.
    • Re:600 years? (Score:5, Insightful)

      by joshuac ( 53492 ) on Monday October 21, 2002 @08:43PM (#4500980) Journal
      from the article:

      Detailed observations of its trajectory through space show that 2002 AA29 will reach its minimum close approach to the Earth - 12 times the distance between Earth and the Moon - at 1900 GMT on 8 January 2003.

      It will be closest to Earth in 2003, and will be nearby for awhile after. As it is much, much closer than Mars, it very well may become the next body visited.
    • Well shit, in 600 years I'll take my own goddamm air car and go visit it myself. Needless to say I'm still impatiently awaiting my cure for old age and (naturally) my flying cars but these are pesky details...
    • I *pray* (and I am not a religious man, so it gets confusing... who shall I pray to tonight?) that we will visit something else before 2600. Preferably in my lifetime, but I guess that's not important in the long-term sense.

      If we spent a little money on it (a little compared to, say, what we spend on defense) we could go to mars NOW. Or at least, very soon. All of this bullshit warmongering that we waste our time and money on is really keeping us from greatness. Of course if we didn't spend it on war we'd probably spend it on something dumb like theme parks or big oil.

      We should DEFINITELY have gone to Mars and be actively moving colonists there long before 2600, barring some kind of serious event. It's just going to become too lucrative not to for some reason or another.

  • by Anonymous Coward on Monday October 21, 2002 @08:34PM (#4500924)
    But despite detailed searches no one has yet found any Trojan objects near the Earth. Next come the inter-stellar port scans.
  • by StupendousMan ( 69768 ) on Monday October 21, 2002 @08:35PM (#4500928) Homepage

    JPL has a very nice tool for looking at the orbits of asteroids. Go to []

    for the general case. For 2002AA29 in particular, you can use roup=all&search=Search []

    Keep in mind that the orbital solution is based on only a short arc: only 28 days, about one twelfth of a complete revolution. Our estimates of the orbital parameters -- and behavior -- could change quite a bit over the next few months.

  • by Randar the Lava Liza ( 562063 ) on Monday October 21, 2002 @08:35PM (#4500933) Homepage
    They better not have any of those metric conversion errors if they try this operation:
    Some have speculated that it could be nudged into a permanent Earth orbit where it could be studied at greater length.
    cough Mars Climate Orbiter cough.
  • by Talisman ( 39902 ) on Monday October 21, 2002 @08:35PM (#4500937) Homepage
    Earth: "MOMMMMMMM! AA29 won't leave me alone! Please tell him to play on the other side of the solar system?!?"

  • The Earth of course revolves around the sun completing one revolution every year, but the Moon also revolves around the Earth in its own orbit.

    Whether this new planet is actually a satellite of Earth is still to be determined. Also, a similar orbit does not mean that the climate is also known to be similar a priori.

    The Earth's ecliptic orbit in summation with the Moon's orbit around the Earth means that the Moon must intersect the ecliptic; in fact, it will have to do so at two distinct points.

    Has anyone found these nodal points for "Earth's Little Brother" yet? That's the true test of whether or not we will truly be affected by such circumstances.
  • "Nudge" it? (Score:5, Funny)

    by Eagle7 ( 111475 ) on Monday October 21, 2002 @08:37PM (#4500944) Homepage
    Some have speculated that it could be nudged into a permanent Earth orbit where it could be studied at greater length.

    I can see it now: "Thanks to a sucessful nudgeing, scientists have been able to determine that Asteroid AA29 is pretty much a big rock. In other news, bizarre tides continue to cause panic and destruction around the world tonight..."
    • by x136 ( 513282 ) on Monday October 21, 2002 @09:44PM (#4501295) Homepage
      NASA Guy 1: "You idiot! We were supposed to nudge it at forty feet per second, not forty meters per se-- Shit! There goes Florida!"

      NASA Guy 2: "I'm in trouble, aren't I?"

      NASA Guy 1: "Uhm, yes. Yes you are."

      NASA Guy 2: "Well, look on the bright side. We get to land in California this time!"
  • by SirSlud ( 67381 ) on Monday October 21, 2002 @08:39PM (#4500955) Homepage
    if there are miniature people in miniature buildings driving miniature SUV's on it .. I'm packin my suitcase and leaving for another galaxy.

    Or, barring that, could our planets swap all the SUVs?
  • Horseshoe orbit? (Score:3, Insightful)

    by jovlinger ( 55075 ) on Monday October 21, 2002 @08:41PM (#4500970) Homepage
    Can sny rocket scientists out there explain how two bodies in the same orbit can have different velocities, AND how the relative velocities can change over time?

    They claim that for 90 odd years, the asteroid will accellerate ahead of us, to catch up with earth from behind, at which point it will fall back and we'll cath up with it. And then it repeats.

    weird! I can't figure out how this is comes about, and the article didn't think it worth mentioning.
  • I mean, come on...if we're as advanced as we seem to think we are, we should have been able to land something on it on jan 8, 2003.

    Yeah, I know, that kind of thing is complex, but I feel we should have that spurious launch capability...god knows it would save us if we ever met something like what hit Jupiter a couple of years back.
    • Yeah, I know, that kind of thing is complex, but I feel we should have that spurious launch capability...god knows it would save us if we ever met something like what hit Jupiter a couple of years back.

      I don't think having a spurious (false, unauthentic) launch ability would permit us to escape fiery death at the hands of a rogue shoemaker-levy-like object. Perhaps you mean extemporaneous. All jokes aside, it would be great to have a near-impromptu method for launching, but unfortunately missions are really expensive and require a great deal of planning. With the derth of funds going towards NASA these days, it should be expected that we won't have improvised launches anytime soon.

    • by Myco ( 473173 ) on Monday October 21, 2002 @09:34PM (#4501254) Homepage
      Yeah, I know, that kind of thing is complex, but I feel we should have that spurious launch capability

      You keep on using that word. I dunna think it means what you think it means.

  • by Anonymous Coward on Monday October 21, 2002 @08:47PM (#4501005)
    ... now have the perfect candidate for their "free" state.
  • But despite detailed searches no one has yet found any Trojan objects near the Earth.

    "The Greeks built an immense wooden horse and Odysseus, Menelaus, and other warriors hid inside it. After leaving the horse at the gates of Troy, the Greek army sailed away. The Trojans thought the Greeks had given up and had left the horse as a gift."

  • by Doomrat ( 615771 ) on Monday October 21, 2002 @08:54PM (#4501049) Homepage
    Has anybody noticed how the BBC news is the best mainstream source for geeky stuff?
  • by Gandalf21 ( 202078 ) <> on Monday October 21, 2002 @09:12PM (#4501151)
    "That's no moon"
  • Use it! (Score:4, Insightful)

    by Docrates ( 148350 ) on Monday October 21, 2002 @09:14PM (#4501164) Homepage
    I wonder how hard it would be to pull that asteroid to earth orbit for mining or as an anchor to a space elevator, a la the [almost] original concept by Arthur C. Clarke (later designs [] use a man made anchor).

    If we can mine useful materials, we could build some cool, big ass stuff probably cheaper than we would carry all that weight from the surface.
  • If we are able to collect enough of these "friendly" asteroids, or "trojans" as the article calls them, we can think of establishing colonies on these. Along with space elevators [], there will be micro-colonies on each of these asteroids, between which people can travel, just like between different continents. The only issue is when the asteroids decide to take a different orbit!

  • Zookeeper Hypothesis (Score:5, Interesting)

    by gnarly ( 133072 ) on Monday October 21, 2002 @10:03PM (#4501363) Homepage
    The Fermi Paradox [] asks: If intelligent life is common, given the billions of years since the formation of our galaxy, why have E.T.'s not yet reached (and perhaps colonized) Earth?

    One proposed resolution [] is the Zookeeper Hypothesis, ie, they could have contacted us but are just waiting and watching for us to evolve, a la 2001.

    If so, then wouldn't they want to put a probe near the Earth, which swoops down every few centuries or so for a close look, to see if any thing interesting has happened?

    • by commodoresloat ( 172735 ) on Monday October 21, 2002 @10:54PM (#4501612)
      Or rather, a question; who's to say that other intelligent life in the universe is anything like our species? The idea that they can and should colonize us, study us, or even visit us seems like the height of anthropocentric hubris. They might not be "flesh-and-blood." They might have a completely different relation to matter and energy as we understand it. They might live in water. They might have no interest in enslaving us or looting our precious natural resources.
  • uh... 'scuse me? (Score:5, Informative)

    by TWX_the_Linux_Zealot ( 227666 ) on Monday October 21, 2002 @10:04PM (#4501372) Journal
    Here [] is Paul Wiegert's [] information on Cruithne, which has much of the same characteristic as this current space body, but his explanation actually makes sense for what appears to be a horseshoe orbit, when in reality it's only a horseshoe orbit from Earth's perspective, and is relatively sane looking when viewed off of the solar system plane.
  • by Tablizer ( 95088 ) on Monday October 21, 2002 @10:09PM (#4501405) Journal

    Little brother? At its size, it is more like a booger of Earth.

    It has a highly complicated orbit. It must be female.

    Some have speculated that it could be nudged into a permanent Earth orbit where it could be studied at greater length.

    Better take out *a lot* of insurance before doing something like that.
  • by Nathdot ( 465087 ) on Monday October 21, 2002 @10:35PM (#4501530)
    So just like that it shows up into our lives and we're meant to be all happy about it.

    And I suppose we're expected to step in if Mercury or Venus start trying to take it's lunch money. And you know they're just gonna have a bigger brother as well. Don't we have enough problems with global warming and the like, without actively looking for trouble?


    2002 AA29:
    You better not pick on me or gonna get my brother earth and he'll kick your ass!

    Oh yeah, I'd like to see him try.


    (sigh, to Mercury)
    I heard you were giving my little brother shit.
    What're you going to do about it now?

    Have you met my brother Jupiter?

    From nowhere the gargantuan JUPITER appears.

    Oh shit! Ay-Ay run!!!

    When will we, the citizens of earth, ever learn that violence never solves anything.
  • by tekrat ( 242117 ) on Monday October 21, 2002 @10:42PM (#4501564) Homepage Journal
    Gosh doesn't anyone read the SF of children's writer Eleanor Cameron?

    She wrote "The Wonderful Flight to the Mushroom Planet", but in "Mr. Bass's Planetoid", she created a tiny asteroid that allowed the two young protagonists to view the Earth while having landed their spaceship on this asteroid.

    Next thing you know, the BBC will report that we've discovered Lepton! Watch out Mushroom People, we're coming!

  • Size Matters (Score:3, Informative)

    by JoeRobe ( 207552 ) on Monday October 21, 2002 @10:53PM (#4501599) Homepage
    I noticed a few people wondering how this would affect our planetary tides, orbit, etc. This would NOT affect the earth at all. Hell, it wouldn't even make that big of a crater if it hit us (why do I think I'm going to get flamed for that?)

    The thing is 100 meters wide. Imagine a 100 meter (300 foot) wide ball. If we just grabbed it and brought it to earth's surface (gently), it still wouldn't affect our tides at all. It's small enough to fit in a stadium. It's the size of a big hill. The point is that it wouldn't affect us at all.

    Also, the reason it wasn't seen that long ago was that it was too far away and too small to see with the naked eye. (we could barely see it with a scope).

  • Confused... (Score:5, Interesting)

    by abhinavnath ( 157483 ) on Monday October 21, 2002 @10:58PM (#4501627)

    How is this object considered a "companion" while Cruithne - Earth's "second moon" - is not?

    Earth's Second Moon []

    2nd Moon Orbiting Earth Discovered []

    Google Search: Cruithne []

    Is there an astronomer in the house? Or anybody who could clarify this?

    • Re:Confused... (Score:3, Informative)

      by BiOFH ( 267622 )
      A companion is not the same as a satellite.
      That's all. A companion describes a similar orbit as another body. The Earth's moons have, necessarily, a slightly different orbit from the Earth if you plot them.

      • Re:Confused... (Score:3, Interesting)

        by abhinavnath ( 157483 )
        I understand the difference between a satellite and a companion. However Cruithne and this body both follow spiral orbits in resonance with the Earth. Neither body orbits the Earth directly. I wanted to know why 2002 AA29 was described as the "first ever" companion object found when 3753 Cruithne was discovered in 1997, and given the discoveries of 1998 UP1 and 2000 PH5.

        See Weigert [] for more information.
  • by vikstar ( 615372 ) on Monday October 21, 2002 @11:53PM (#4501825) Journal
    "it could be nudged into a permanent Earth orbit where it could be studied at greater length."
  • by rendermouse ( 462757 ) on Tuesday October 22, 2002 @10:23AM (#4504558) Journal
    "Some have speculated that it could be nudged into a permanent Earth orbit where it could be studied at greater length. "

    Just what we need. Someone pushing huge space rocks closer to the planet to get a better look.

    Have you never broken a microscope slide by zooming in too far?

Memory fault -- brain fried