We went looking for glowing interstellar gas – and stumbled on 49 unknown galaxies

Stars are born from huge clouds of mostly hydrogen gas floating in space. Astronomers like me study this gas because it helps us understand how stars and galaxies form and grow.

Hydrogen gas gives off a faint glow that is invisible to human eyes but can be observed with a telescope tuned to detect radio waves.

Recently, my colleagues and I were using a telescope like this – a radio telescope called MeerKAT, in South Africa – to look for hydrogen gas in a particular galaxy. We were only observing for less than three hours, which is quite a short amount of time since the…

© La Conversation - lundi 25 mars 2024