Earth's Moon is a Rarity

Smivs writes "Scientists have concluded that moons like the Earth's are actually quite rare. Only 5-10% of planetary systems are likely to contain moons formed by planetary collisions. 'By the time the Earth's moon formed, when the Sun was 30 million years old, the planet formation process in our Solar System should have been approaching its end. In the latest study, Dr Gorlova's team looked at the heat signature of stars using the infrared. This allows astronomers to predict how much of that heat comes from the star itself and how much is re-emitted by dusty material encircling it.'"

Comments

Huge moon

[eebra82]

Not only are moons rare, but earth's moon is actually the fifth largest in our solar system. Considering how small our planet is and how big our moon is, I would say it's probably extremely rare to find similarities like this in the universe.

Rare defined as 5 - 10 percent ?

[dbcad7]

Theres 20 people in the room..1 to 2 of them have a birthmark on their left cheek... how RARE.
Theres 200 people in the room..10 to 20 of them have a birthmark on their left cheek... how RARE.
Theres 2000 people in the room..100 to 200 of them have a birthmark on their left cheek... how RARE.

Given distances between galaxies 5 to 10 percent seems rare, but if distance didn't matter then this percentage is hardly RARE considering the vastness of the universe, and number of galaxies.