Discovered: First Potential Planet Outside of Our Galaxy

This artist’s animation depicts the possible detection of a planet candidate in a double system in the M51 (“Whirlpool“) galaxy. The view begins outside of the galaxy and then travels into the star cluster containing the binary system called M51-ULS. This contains either a neutron star or a black hole in orbit with a star about 20 to 30 times the mass of the Sun (large blue star). The neutron star or black hole is pulling material from its companion star, creating a disk of material that glows in X-rays (red, orange, and yellow). Astronomers using NASA’s Chandra X-ray Observatory detected a decrease in the X-rays from M51-ULS over about a 3-hour period. They interpret this dimming as being a “transit,“ when a planet passing in front of the disk along the line of sight to Earth and blocks some or all of the light. This is depicted in the animation as the planet moves across the view from left to right and the bright light from material close to the neutron star or black hole briefly dims. By searching for exop