Tour: Chandra Sees Evidence for Possible Planet in Another Galaxy

Astronomers have announced that they have found evidence for the first possible planet discovered outside of our Milky Way galaxy. To do this, they used a technique looking for the temporary dimming of X-rays from an object with NASA's Chandra X-ray Observatory. This intriguing result could open up a new window for exploring exoplanets — that is, planets outside our Solar System — at greater distances than ever before. Until now, astronomers have found all known exoplanets — defined as planets outside of our Solar System — and exoplanet candidates in the Milky Way galaxy. Most of these have been less than about 3,000 light-years from Earth. This new Chandra study looks at a system in the Messier 51, or M51, galaxy. This galaxy is nicknamed the “Whirlpool“ galaxy because of its spiral shape. It is located about 28 million light years from Earth. One system in M51 in particular caught the attention of a research team. This system, known as M51-ULS-1, belongs to a class of objects that astronomers call X-ray