Minimoons?

[aramis]

http://www.universetoday.com/114212/hunting-for-minimoons-orbiting-earth/

What if Earth had multiple moons? Our world has one large natural satellite, just over a quarter the diameter, 1/50th the volume, and less than 1/80th the mass of our fair world. In fact, the Earth-Moon system has sometimes been referred to as a “binary planet,” and our Moon stands as the largest natural satellite of any planet — that is, if you subscribe to bouncing Pluto and Charon out of “the club” — in contrast to its primary of any moon in our solar system.​

One confirmed mini-moon...

 

[BlackBat242]

I didn't see that in the article you linked - could you link your source?

 

[Timerover51]

It would be more interesting if the Earth-Moon system had mini moons at the LaGrange Points. There probably is some debris there if anyone checked.

 

[Hovtej]

It would be more interesting if the Earth-Moon system had mini moons at the LaGrange Points. There probably is some debris there if anyone checked.

A few have been found. Here is a link to a note on the first:
http://www.nasa.gov/mission_pages/WISE/news/wise20110727.html

 

[WistfulD]

It would be more interesting if the Earth-Moon system had mini moons at the LaGrange Points. There probably is some debris there if anyone checked.

True, but the LaGrange point requires the moon we have... Aramis, did you mean to ask what if the Earth had minimoons instead of, or along with, the moon that we have?

We have an example of a rocky planet with smaller moons. Mars' Phobos and Deimos are pretty good examples of a small and a very small moon. They barely seem to have any effect on the planet (although if Mars had an ocean, I suppose that might change the math).

 

[aramis]

I didn't see that in the article you linked - could you link your source?

"The convoluted orbit of 2006 RH120 around the Earth-Moon system, to date the only confirmed TCO. Credit: Wikimedia Commons/Ohms law."

The 2nd non-photo graphic. Helps if you actually read the whole thing.

 

[BlackBat242]

Temporary Capture Object - not permanent minimoon.

It helps if you read the definitions of the abbreviations.

 

[BlackBat242]

It would be more interesting if the Earth-Moon system had mini moons at the LaGrange Points. There probably is some debris there if anyone checked.

A few have been found. Here is a link to a note on the first:
http://www.nasa.gov/mission_pages/WISE/news/wise20110727.html

Those are at the Earth-Sun LaGrange points, in the Earth's orbit part-way around the sun from the Earth - not at the Moon's LaGrange points in orbit around Earth.

 

[Hovtej]

Missed the Earth-Moon constraint. There have been proposals to send probes to the Earth Trojans.

There was an extensive photographic survey by Clyde Tombaugh after WW-II looking for Earth minimoons that did not detect any at that time down to 13th magnitude. As far as I know, that is the only large-scale systematic search for Earth-orbiting minimoons. I've used some of his techniques to search for artificial satellites.

 

[aramis]

Temporary Capture Object - not permanent minimoon.

It helps if you read the definitions of the abbreviations.

Never claimed it was permanent, BB...

 

[Hovtej]

3753 Cruithne Minimoon

More Minimoon information:
http://www.iflscience.com/space/ear...azy-orbit-could-reveal-mysteries-solar-system

 

[JimMarn]

There are supposedly mini-moons at the Earth LaGrange points. Jupiter and Saturn have lots of mini-moons.

I think it would be nice for us to have a share of them. But as pointed out up thread, likely only temporary ones.