Zooming into Andromeda: The Andromeda galaxy contains about one trillion stars and is approximately 220,000 light years in diameter. This image was put together using the sharpest photograph of Andromeda ever taken. (Credit: NASA/ESA)
Zooming into Andromeda: The Andromeda galaxy contains about one trillion stars and is approximately 220,000 light years in diameter. This image was put together using the sharpest photograph of Andromeda ever taken. (Credit: NASA/ESA)