Scientists announced today the discovery of a fifth planet in a distant star system that that now looks like a "cousin" to our own. Known as 55 Cancri, the sun-like star harbors the most number of planets ever discovered outside our solar system.
Four of the planets had been previously detected, but the existence of the fifth planet took 18 years to confirm. It is about 45 times more massive than Earth and might be similar to Saturn in its composition and appearance.
55 Cancri is located 41 light-years away in the direction of the constellation Cancer and is visible with binoculars. The system contains a clutch of four inner planets that are separated from an outer planet by a huge gap.
The newest member of Cancri 55's family lies within the star's habitable zone, the region around the star within which water can exist in its liquid state. Though the planet is a giant ball of gas, liquid water could exist on other, currently undiscovered rocky planets in the system.
Such a potentially habitable planet could reside in the nearly 700 million-mile (1.1 million-kilometer) wide space that separates 55 Cancri's four inner planets and its outer one.
Another possibility is that a moon in orbit around 55 Cancri's newly confirmed planet could harbor liquid water, and perhaps life, the researchers say. If there were a moon around this planet, it would have a rocky surface. Water on it could in principle puddle into lakes and oceans, serving as the solvent for biochemistry.
Kemo D. (a.k.a. no.7)