Astronomers have used ESO’s VLT Survey Telescope to produce a stunning new image of a large stellar nursery called the Prawn Nebula.
This image shows the Prawn Nebula. Image credit: ESO. Acknowledgement: Martin Pugh.
The Prawn Nebula, also known as IC 4628, is located in the constellation of Scorpius about 6,000 light-years away. The object is around 250 light-years across, covering an area of sky equivalent to four times that of the full Moon.
Despite this huge size the Prawn Nebula has been often overlooked by observers due to its faintness and because most of its light is emitted at wavelengths where the human eye is not sensitive.
It is a huge region filled with gas and clumps of dark dust. These gas clouds are star-forming regions, producing brilliant hot young stars. In visible light, these stars appear as a blue-white color, but they also emit intense radiation in other parts of the spectrum.
It is ultraviolet light from the stars that causes the gas clouds to glow. This radiation strips electrons from hydrogen atoms, which then later recombine and release energy in the form of light. Each chemical element emits light at characteristic colors when this process occurs, and for hydrogen the predominant color is red. The nebula is an example of an HII region. Astronomers use the term HII to refer to ionized hydrogen, and HI for atomic hydrogen.
The Prawn Nebula is also known as Gum 56, after the Australian astronomer Colin Gum, who published a catalogue of HII regions in 1955.
Over the last few million years this region of sky has formed many stars, both individually and in clusters.
There is a large scattered star cluster named Collinder 316 which extends over most of this image. This cluster is a part of a much larger gathering of very hot and luminous stars. Also visible are many dark structures or cavities, where interstellar matter has been blown away by the powerful winds generated by the nearby hot stars.
