Homeless planets become more common

The+definition+of+a+planet+is+a+celestial+body+moving+in+an+elliptical+orbit+around+a+star.+The+sun+of+the+Milky+Way+is+4.6+billion+years+old.+Mars+and+Earth+have+about+the+same+land+mass.+%0APhoto+Credit%3A+MCT+Photo%0A

MCT

The definition of a planet is a celestial body moving in an elliptical orbit around a star. The sun of the Milky Way is 4.6 billion years old. Mars and Earth have about the same land mass. Photo Credit: MCT Photo

In science class you are taught that a galaxy is composed of planets, gases, and stars. Recent findings have shown that it maybe common for planets to be on their own and not have any source of warmth or parent star.

The first time something of this manner was discovered was in computer simulations in the 1970s. But the first actual sighting of these rouge planets was in the early 2000s. In the past 15 years scientists have discovered 50 of these lone planets.

This challenges the standard definition of a planet, yet most of them have all of the general characteristics of a planet just without a parent star.  In our own Milky Way planet PSO J318.5-22 is homeless as well, not drifting the star.