
In a research paper called “The population of natural Earth satellites”, astronomers say that Earth must have a second moon at any given time. They have calculated the population of “irregular natural satellites that are temporarily captured” by Earth.
Their calculations have been confirmed by an actual observation, a mysterious titanium white object that was discovered rotating around Earth in 2006 by the Catalina Sky Survey in Arizona.
Our results are consistent with the single known natural [temporarily-captured orbiter] 2006 RH120, a few-meter diameter object that was captured for about a year starting in June 2006.
That object was actually a small asteroid captured by Earth’s gravitational field, and it rotated as a second moon until June 2007, when it left its orbit. This study demonstrates that, even while they are not detected, these little moons come and go often, staying around for about ten months, take about three spins around the planet and then wave goodbye.
Imagine being able to detect one of these tiny moons and send a few astronauts to capture it instead of getting them to a distant one. The information that we can obtain could be phenomenal. And without having to spend a lot of money.
Now, let the Death Star jokes begin. [Cornell University via MIT Technology Review]
Base landscape image by James Thew/Shutterstock
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Matt
Wednesday, December 21, 2011 at 9:06 AMTracter beam FTW!
olearymo
Wednesday, December 21, 2011 at 9:09 AMThat’s no moon, that’s a temporarily captured orbiter of a few metres in diameter!
Jot
Wednesday, December 21, 2011 at 9:11 AMDoes that mean we enter 2Q11 when ever a second moon arrives?
Nathan
Wednesday, December 21, 2011 at 9:16 AMthats no moon…
cayal
Wednesday, December 21, 2011 at 9:21 AM“staying around for about then months”
Creating new numbers eh Giz?
Greg
Wednesday, December 21, 2011 at 9:29 AMIt’s an algebraic term, instead of x = it’s then = ….
steve
Wednesday, December 21, 2011 at 9:31 AMTheta my favourite number, leave it alone
Freeman
Wednesday, December 21, 2011 at 11:20 AMIt’s a trap
QBall
Wednesday, December 21, 2011 at 5:10 PMLOL’d @ Freeman
Just This Guy ...
Wednesday, December 21, 2011 at 1:58 PM” take about three spins around the planet and then wave goodbye. ”
Bloody tourists!
Josh
Wednesday, December 21, 2011 at 7:01 PMI’m guessing noone here’s watched QI?
Cedestra
Thursday, December 22, 2011 at 12:35 PMIt was the first thing I thought of. Poor Rich Hall…
Sean Robert Meaney
Wednesday, December 21, 2011 at 7:27 PMA Titanium Moon a few meters in diameter? Lets see if the next one is the technological equivalent of RAMA II.
Peter
Thursday, December 22, 2011 at 8:33 AMMoons don’t “rotate” around the Earth … they “revolve” … they rotate about their own axes…
RB
Wednesday, December 21, 2011 at 10:22 AMThe were ever high?
RB
Wednesday, December 21, 2011 at 10:23 AM*must proof-read comment proof-reading before posting*
michael
Wednesday, December 21, 2011 at 10:49 AMIf you dont like it mate, stop coming back. . .
seems to me the answer is very simple. . .
RB
Wednesday, December 21, 2011 at 10:24 AMI give up :’(
Sam
Wednesday, December 21, 2011 at 10:32 AMAt least you spelt that one right :P