NGC2244 is formal code of the star open cluster placed about 5000 light years away in the constellation Monoceros (Unicorn). The stars in this cluster are very young – the age is estimated to be less than 5 million years. They are hot and extremely luminous – brightest stars in this cluster are several hundreds thousands brighter than Sun!
Open star cluster are usually not so exciting – just a bunch of stars placed close together. But in case of NGC2244 since they are so young there are still a lot of stuff the stars have been formed from. The star cluster is immersed in the large cloud of molecular hydrogen, and the stellar winds from the stars of the cluster are excerting pressure on interstellar clouds to cause compression followed by star formation that is still ongoing. This hydrogen cloud that surrounds NGC2244 star cluster is named Rosette Nebula.
X-ray observations of Rosette Nebula shows that its center emits copious amounts of X-rays due to the fact, that hot and young stars in the nebula center have heated surrounding gas to temperature 6 million kelvins. It seems to be quite intense place in the Universe.
The picture below has been taken on Valentine’s day of year 2014 during the Full Moon, so the result is not quite excellent. 3 hours total exposure in hydrogen alpha emission line:
Only a center part of Rosette Nebula is shown – the nebula itself spans about two times wider.
Update – after making some required calibration flat files I processed the whole frame, so here it is: