NGC 588

NGC 588 is a prominent, giant H II ionized diffuse nebula located in the outskirts of the galaxy Messier 33's spiral arms, within the Triangulum constellation. The nebula has two Wolf-Rayet stars, NGC 588-UIT 008 and NGC 588-MC3 and a fairly large population of main sequence stars of 2 to 20 solar masses. The more massive stars in the nebula have a mass of around 40 solar masses. NGC 588 is 4.2 million years old and has a mass of 2300 solar masses.

NGC 588 and NGC 592 (another nebula in the Triangulum galaxy) are both very prominent stellar nurseries in their regions.

Discovery
It was discovered October 2, 1861 by the German-Danish astronomer Heinrich d'Arrest.