NGC 2404

NGC 2404
Emission nebula
H II region
NGC 2404 is the giant H II region to the left
Observation data: J2000 epoch
Right ascension07h 36m 51.4s
Declination+65° 36 09
Distance9,650,000 ly   (2,960,000 pc)
Apparent magnitude (V)+16.9
Apparent dimensions (V)20 arcsecs
ConstellationCamelopardalis
Physical characteristics
Radius470 (estimated) ly
Absolute magnitude (V)-14.5
Notable featuresMassive H II region,
the largest one in NGC 2403.

NGC 2404 is a massive H II region inside NGC 2403, a spiral galaxy in Camelopardalis. It was discovered on February 2, 1886 by Gulliaume Bigourdan. NGC 2404 is approximately 940 ly in diameter, making it one of the largest H II regions so far known. It is the largest H II region in NGC 2403, and lies at the outskirts of the galaxy, making for a striking similarity with NGC 604 in M33, both in size and location in the host galaxy. This H II region contains 30-40 Wolf-Rayet stars, and unlike the Tarantula Nebula, but similar to NGC 604, NGC 2404's open cluster is probably much less compact, so it probably looks like a large stellar association. This H II region is probably only a few million years old.