WHAT’S THE NEXT NEAREST GALAXY TO OURS, AND WHAT’S THE CHANCE OF THERE BEING ANOTHER EARTH IN IT?
Tom Sawicki
The next nearest galaxy is actually inside our own galaxy. It’s called the Canis Major Dwarf Galaxy, and eventually it will be completely absorbed by our Milky Way. It contains around a billion stars, compared to the 200 billion in the Milky Way. The nearest big galaxy to ours is Andromeda, which lies around 2 million light years away.
Astronomers have discovered nearly 5,000 planets around stars other than the Sun, but most of these resemble gas giants like Jupiter rather than our rocky Earth. New telescopes have revealed more Earth-like planets, but it’s still very hard to detect a small planet orbiting a distant star.
Most of the extrasolar planets so far confirmed have been in the Milky Way, as it’s very difficult to spot something as small as a planet in another galaxy. But theorists think that there could be billions of Earth-like planets in our own galaxy, and a similar number in others. Somewhere out there, extraterrestrials may be waiting…