It is the third known planet in order of distance from its star.
This is much older than any other known planet, and nearly three times as old as Earth.
It was much more like an unfamiliar part of a known planet than a new world altogether.
Before 1991, the worlds of our own solar system were the only known planets.
We were able to photograph not only the Earth, but also five other of the Sun's nine known planets.
At the time of the discovery it was the only known planet in an open cluster.
The two known planets appear to have a 2:1 resonance with one another.
The star has a M0 class companion and but no known planets.
The primary star has a single known planet, discovered in 2005.
The system is approximately 8700 million years old, and does not contain any known planets.