IRAS stands for Infrared Astronomical Satellite. It was a space telescope launched in 1983 that observed the sky in infrared light. It wasn't a galaxy itself, but a tool used to study galaxies and other celestial objects.
To compare the brightness of a galaxy to the sun, you would need to know the absolute magnitude of the galaxy and the sun. Then, you can calculate the difference in their luminosities.
Let me know if you want to compare the brightness of a specific galaxy to the sun!
