Red cocoon harbours young stars

On Earth, cocoons are associated with new life. There are “cocoons” in space too, but, rather than protecting pupae as they transform into moths, they are the birthplaces of new stars.

The red cloud seen in this image, taken with the EFOSC2 instrument on ESO’s New Technology Telescope, is a perfect example of one of these star-forming regions. This is a view of a cloud called RCW 88, which is located about ten thousand light-years away and is about nine light-years across. It is not made of silk, like a moth’s cocoon, but of glowing hydrogen gas that surrounds the recently formed stars. The new stars form from clouds of this hydrogen gas as they collapse under their own gravity. Some of the more developed stars, already shining brightly, can even be seen peering through the cloud.

These hot young stars are very energetic and emit large amounts of ultraviolet radiation, which strips the electrons from the hydrogen atoms in the cloud, leaving the positively charged nuclei — protons. As the electrons are recaptured by the protons, they can emit H-alpha light, which has a characteristic red glow.

Observing the sky through an H-alpha filter is the easiest way for astronomers to find these star-forming regions. A dedicated H-alpha filter was one of the four filters used to produce this image.



À propos de l'image

Date de publication:30 juillet 2012 10:00
Taille:937 x 914 px

À propos de l'objet

Nom:RCW 88
Type:Milky Way : Nebula : Type : Star Formation
Distance:10000 années lumière

Image Formats

Grand JPEG
288,0 Kio
JPEG taille écran
227,6 Kio


Fonds d'écran

231,3 Kio
372,5 Kio
535,2 Kio
621,7 Kio
822,6 Kio


Position (RA):15 7 7.89
Position (Dec):-57° 48' 18.28"
Field of view:3.76 x 3.67 arcminutes
Orientation:North is 0.0° left of vertical