New 'moon' found around Earth

[Dover]

New 'moon' found around Earth

By Dr David Whitehouse
BBC News Online science editor

An amateur astronomer may have found another moon of the Earth. Experts say it may have only just arrived.

Much uncertainty surrounds the mysterious object, designated J002E3. It could be a passing chunk of rock captured by the Earth's gravity, or it could be a discarded rocket casing coming back to our region of space.

It was discovered by Bill Yeung, from his observatory in Arizona, US, and reported as a passing Near-Earth Object.

It was soon realised, however, that far from passing us, it was in fact in a 50-day orbit around the Earth.

Paul Chodas, of the American space agency's Jet Propulsion Laboratory in California, says it must have just arrived or it would have been easily detected long ago.

Calculations suggest it may have been captured earlier this year...cont'd

http://news.bbc.co.uk/1/low/sci/tech/2251386.stm

[Ian David]

1. That would make moon number 3 (sort of)

I never knew we had a SECOND (sort-of) moon already...

http://burtleburtle.net/bob/physics/cruithne.html
ere are some simulations of Cruithne, also known as asteroid 3753, or 1986 TO, or "Earth's second moon". Many thanks to Graeme Waddington who supplied the xyz coordinates of Cruithne and the planets as of February 26 2000, and Paul Wiegert, Kimmo Innanen, and Seppo Mikkola whose research is responsible for most of what we know about Cruithne. (The coordinates are embedded in this html file, they are parameters to the gravitational simulation applet.)

Cruithne is not really a moon, because Earth and Cruithne are not gravitationally bound. (Luna IS a real moon.) But Cruithne is locked into a 1::1 resonance with Earth. (Another resonance in the solar system is the 3::2 resonance of Neptune and Pluto. That means Neptune makes 3 orbits for every 2 of Pluto.) Cruithne's nearest pass to Earth is .1 AU (40 moon lengths), although right now it never comes closer than .3 AU. It is 5 kilometers (3 miles) wide.

[TwilightZone]

2. Hmm, that article is more than two years old.

Was the object ever confirmed?

[muriel_volestrangler]

4. According to this site, it was probably a rocket stage

3rd stage of Apollo 12, and left earth oprbit after about 9 months.

http://www.birtwhi.demon.co.uk/GallerySatelliteJ002E3.htm

This site is a NASA diagram of how it 'orbited' in that time. Cool.

http://neo.jpl.nasa.gov/j002e3a.html

[Trajan]

3. "Don't Need Another Satellite" ....

Another Satellite

Lyric by: Andy Partridge, XTC


My heart is taken it's not lost in space
And I don't want to see your mooney mooney face
I say why on earth do you revolve around me ?
Aren't you aware of the gravity ?

Don't need another satellite

I'm happy standing on my feet of clay
I have no wish to swim your milky milky way
I say why on earth do you send your letters 'round here ?
Only to gum up the atmosphere

Don't need another satellite

So circling we'll orbit another year
Two worlds that won't collide
So circling we'll orbit another year
Moon still tries to steal the tide away

Don't need another satellite
Don't need another satellite

Abort your mission let's just say you tried
Before you glimpse I have a darker darker side
I say why in Heaven's name do you come on these trips ?
Only to freeze in a total eclipse

Don't need another satellite

So circling we'll orbit another year
Two worlds that won't collide
So circling we'll orbit another year
Moon still tries to steal the tide away

Don't need another satellite
Don't need another satellite