We have company: Asteroid discovered in Earth’s orbit

[ej510]

Source: The Star



The Earth has its own well-behaved celestial Chihuahua on a leash.

Two Canadians astronomers are among a team that has discovered our planet’s first Trojan asteroid, which is rotating the sun in our orbit.

“The interesting thing is that it is synchronized with the Earth,” Professor Paul Wiegert of the University of Western Ontario told the Star on Thursday.

“The asteroid always remains a little ahead, like a dog on a leash.”

>snip

“This asteroid is among the safest,” said Wiegert. “It never gets particularly close to the Earth, but it doesn’t wander too far away. There is a distinct gravitational link”

Read more: http://www.thestar.com/news/canada/article/1031516--we-have-company-asteroid-discovered-in-earth-s-orbit?bn=1

[Wednesdays]

1. If it's within earth's "gravitational link," doesn't that make it another natural satellite (moon)?

:shrug:

[fxw]

3. A moon would orbit the planet, not the sun. n/t

[Wednesdays]

9. When you think about it,

everything in the solar system orbits the sun.

The article implies this new object's orbit is within earth's gravitational sphere, and earth is influencing its orbit. If we sent up an artificial satellite that hovers in circles above the earth without circumventing it (I think such satellites do exist), is it not still a satellite?

[N7Shepard]

44. This isn't entirely new

http://en.wikipedia.org/wiki/3753_Cruithne

[TheMadMonk]

53. Try plotting the orbit of the moon relative to the sun. /nt

[ej510]

4. You would think so, but maybe the scientists believe it isn't due to its mass.

[Wednesdays]

11. That may be it...although,

a lot of the satellites recently discovered around the giant planets by Voyager, etc., are pretty tiny.

[ej510]

13. True, we will have to wait until more studies are done in order to find out.

[immoderate]

17. No. It's at a LaGrange point in the Earth-sun system.

That asteroids could perform such complicated motions while staying in step with their companion planets was first proposed by Joseph Louis Lagrange in 1772.
http://www.astro.uwo.ca/~wiegert/2010TK7/index.html

LaGrange explained that there are five points where gravity is neutral in a planetary system. At two of those points, roughly sixty degrees of orbit, gravitational forces of the larger objects create a virtual depression, that "locks" objects that find that spot.

--imm

[immoderate]

22. Here's a LaGrange diagram.

L4 and L5 are stable. That's where asteroids get "captured."

--imm

[Devil_Fish]

42. WOW there could be another planet locked in L3 and we would never know!!!!

[MicaelS]

46. No, we would know it's there .....

Because of the gravitational force it would exert. http://en.wikipedia.org/wiki/Counter_Earth

If such a planet actually existed, according to present scientific cosmology, it would be permanently hidden behind the sun but nevertheless detectable from Earth, because of its gravitational influence upon the other planets of the Solar System. No such influence has been detected, and indeed space probes sent to Venus, Mars and other places could not have successfully flown by or landed on their targets if a Counter-Earth existed, as it was not accounted for in navigational calculation.

It must also be noted that the Earth orbit is not a circle but an ellipse, and in respect of Kepler's second law, a planet revolves faster when it is close to the star. So if the Counter-Earth followed the Earth on the same orbit with half a year of delay, it would sometimes be visible from Earth. Rather, to be hidden from Earth, the Counter-Earth would have an orbit symmetrical to Earth's one, not sharing the second focus.

Any planetary sized body at Earth's L3 point should have been visible by the NASA STEREO coronagraphs during the first half of 2007. The separation of the STEREO spacecraft from Earth would give them a view of the L3 point during the early phase of the mission. Later, as the spacecraft continued to separate, the L3 point drifted out of the field of view. Given the sensitivity of STEREO's COR2 coronagraph, anything larger than 100 kilometres (62 mi) in diameter should have been detected.

[sofa king]

48. John Norman has you covered....

http://en.wikipedia.org/wiki/Counter-Earth

http://en.wikipedia.org/wiki/Gor

[immoderate]

51. Only L4 and L5 have the "lock."

The other points are not stable in all the spatial dimensions.

--imm

[guitar man]

55. Aha!

That would explain the unusual radio signal it's emitting :silly:

http://www.youtube.com/watch?v=Vppbdf-qtGU

[appal_jack]

26. That's no moon...

[Tesha]

36. Well in that case, we'd better "Orbit casual!" (NT)

[MicaelS]

47. No, because it is in SOLAR orbit, not Earth Orbit. n/t

[KaryninMiami]

2. Oh goody- maybe they'll send help. We could sure use it. NT

[truthisfreedom]

5. Why do I get the funny feeling that this asteroid doesn't want us to know it's there?

How long did it take us to discover this thing? With all of the probes we've sent out? All of the calculations we've done regarding our own orbit?

[Auggie]

12. Just underscores how much we don't know, I guess

[Wednesdays]

18. It's just very shy, that's all.

That, and it's ability to disguise itself as a black hole, etc.

[Atypical Liberal]

23. don't be too alarmed.

All the "probes" we have sent out are not like Star Trek where they have the ability to magically image everything up to the color of the protagonist's underwear.

Our probes are designed to measure very specific things. Searching for asteroids has probably not been among them.

Asteroids are difficult to detect, because they reflect little light. The way most of them are detected is through multiple exposures of the same point of sky, and looking for differences in the pictures.

They are difficult to spot.

[booley]

30. Yes, very suspicious

I mean it's not as if it's a very small rock and space and is really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really really to the gizzilionth power big.

:silly:

[FLPanhandle]

32. and really dark floating against a really dark background.

Yep, big surprise.

[Blue_Tires]

31. Because that's where the Monolith is, Mister Silly!

:silly:

[FLPanhandle]

33. Asteriods think?

:rofl:

[freshwest]

45. Maybe it's a UFO spying on us! Oh no!

:hide:

[Hubert Flottz]

6. Well kiss my asteroid!

That might be a good place to send Sarah Palin...she could be number one there!

[Liberalynn]

14. Its not far enough away.

;) It needs to be an asteroid much farther away from Earth.

[Morizovich]

7. Trojan Asteroid?

So, even if it hits us, we won't get pregnant or catch a disease? Great!

[Myrina]

8. Can we send the Tealiban there?

They can start their own 'government free, tax free' colony. Buh bye.

[bitchkitty]

25. Nah, the asteroid is Obama's birthplace. n/t

[Permanut]

10. So now we have to figure out who owns it...

I nominate myself, although I'm not sure what I'm gonna do with it.

[Firebrand Gary]

15. It's GOING to hit earth, that's why we have all of the temp activity with the space station.

Tin Foil?

[immoderate]

20. No, it's actually locked in orbit at the L4 point.

Read up on Trojan satellites. :)


--imm

[DeSwiss]

16. You ain't seen nothin' yet. :^D - K&R n/t

[Towlie]

19. What the hell does "trojan" have to do with "tango"?

Most asteroids are clustered in a belt near Mars. While Trojan asteroids, named because of the complicated “tango” they perform with planets, were proposed in 1772...

The tango is a dance that originated in South America, while "Trojan" refers to the ancient city of Troy in what is now Turkey. Where's the connection?

[ChrisBorg]

24. The use of "Trojan" is a historical convention. They were first predicted to be in Jupiter's orbit.

The naming convention for the Trojans in Jupiter's orbit was to name them after figures from the Trojan War.

[Towlie]

28. Right. So they weren't "named because of the complicated 'tango' they perform with planets."

Just as I figured, that part of the article doesn't make sense.

[immoderate]

35. They were two metaphors, from seperate sources, that didn't "mix."

Objects captured at LaGrange Points, L4 and L5, are called Trojan because they were first discovered aroung Jupiter, although they had been predicted long before, in 1772.

Those points are gravity wells. Objects caught in them will revolve around it's center, like a marble rolling around a funnel. It's path, as traced in the illustration, is the "tango" part.

--imm

[sofa king]

52. The Trojans in Jupiter's L4 are broadly described as the "Greek camp."

While those at L5 are in the "Trojan camp."

A nice little tip of the hat to The Illiad. However, the naming convention was apparently already compromised before the decision to divide the Trojans into "camps." So poor Achilles is forever separated from his buddy Patroklos. Zeus (Jupiter) won't have it any other way, because of what Achilles did to Sarpedon.

There's a little project for those of you who dabble in space science and gay marriage: with some ion rockets and a whole lot of time and money, Patroklos could be moved to L4 so that the two can be reunited in heaven. And while you're at it, put Hektor in the Trojan camp where he belongs, too!

[sofa king]

56. But now that I think of it....

After Achilles knocked off Hektor, he desecrated his dead body by tying it to the back of his chariot and dragging it around the camp and the walls of Troy. (In so doing he burned off the last of his credit with the gods, and one of them told Paris about Achilles' heel....)

So perhaps the naming of Hektor in the Greek camp was intentional.

[TalkingDog]

40. Tango = dance Trojan = secret thing you didn't know was there

in this context.


no connection, just a reporter working through the T's in the metaphor dictionary.

[Poll_Blind]

21. It's the Compass Army from Planet Spirograph!

At least the battle hopefully won't be...protracted.

:hide:

PB

[existentialist]

27. I also understand that there's a

"cat and mouse" asteroid that roughly shares the Earth's orbit too, except that it goes a little faster on a track slightly nearer the sun until it catches up. Then interaction with Earth's gravity slows it down and puts it on a slightly further out orbit until the Earth catches up with it.
Then the Earth's gravity puts it in a slightly more inside and faster orbit until it again catches up with the Earth, and the sequence is repeated.

[StarsInHerHair]

29. funny, I thought the celestial Chihuahua was our moon

[FLPanhandle]

34. "dog on a leash"? I prefer "Dolphin riding our bow wave".

Cool Stuff.

[immoderate]

39. More like a dolphin on a leash, riding our bow wave?

It can't leave the area. :shrug:


--imm

[Evasporque]

37. It is another defender of the Earth...like the moon...nt

[bmbmd]

38. Gateway?

One of my favorite sci fi series...

[bikebloke]

41. Another Earth

http://www.youtube.com/watch?v=qB50aBrHbu4

[sarcasmo]

43. Time to call Bruce Willis and Ben Afleck.

[left on green only]

50. I Always Thought It Best

to use Preparation H on an asteroid. Yeah, I know, "That's what she said".:shrug:

[paparush]

49. No one's seen Cheney in a while... COINCIDENCE?

[and-justice-for-all]

54. Is it occupied by chance?

"“It never gets particularly close to the Earth, but it doesn’t wander too far away"???
"“The interesting thing is that it is synchronized with the Earth,” "????

and we never noticed this before?????

[Occulus]

58. Black object, black background

Tiny little rock, great big-ass sky.

No real surprise.

[LetTimmySmoke]

57. I hope its safer than the leash on the teabaggers.

[octothorpe]

59. I've seen this before. It's an alien base disguised as an asteroid.

We need to nuke this thing ASAP.

[piedmont]

60. I WANT TO GO TO THERE

srsly. let's go NASA.