The Andromeda Galaxy

The Andromeda Galaxy, also known as Messier 31 or M31, is a spiral galaxy located approximately 2.5 million light-years away from Earth in the constellation Andromeda. It is the closest galaxy to the Milky Way and is one of the brightest objects in the night sky.

The Andromeda Galaxy is approximately 220,000 light-years in diameter, making it slightly larger than the Milky Way. It is estimated to contain around one trillion stars, which is more than twice the number of stars in the Milky Way.

The Andromeda Galaxy is also home to several satellite galaxies, including M32 and M110, which are visible in small telescopes. Astronomers have observed that the Andromeda Galaxy is approaching the Milky Way at a rate of about 110 kilometers per second, and the two galaxies are expected to collide in about 4.5 billion years. This collision is expected to result in the formation of a new galaxy, often referred to as Milkomeda.