Astronomers based in Arecibo Observatory in Puerto Rico report that they have discovered the first triple asteroid near planet Earth.

The system is called 2001 SN263 and is just 7 million miles (11.2 million kilometers) away from us. The system was originally found in 2001 but it is only now that astronomers have confirmed that is in fact three gravitational bound rocks.

Cornell University and Arecibo astronomer Michael C. Nolan had this to say:

This discovery has extremely important implications for ideas about the origins of near-Earth asteroids and the processes responsible for their physical properties.

Double, or binary, asteroid systems are known to be fairly common about one in six near-Earth asteroids is a binary but this is the first near-Earth triple system to be discovered.

Examining the orbits of the moons as we continue to observe 2001 SN263 over the next few weeks may allow us to determine the density of the asteroid and type of material from which it is made.

We will also be studying its shape, surface features and regolith [blanketing material] properties.