A dark ‘nursery’ cloud of dust where new stars are forming has just been imaged in a brilliant new photo taken by the European Southern Observatory. The image clearly shows the process by which enormous masses of dust and gas coalesce into stars. The only truly significant difference between the dark cloud and the stars is the density, somewhat like a diamond in a handful of coal.
The new image was captured with the MPG/ESO 2.2-meter telescope at the La Silla Observatory in Chile. It is currently the clearest image that has been taken (in the visible spectrum) of the somewhat unknown object.
“On the left of this new image there is a dark column resembling a cloud of smoke. To the right shines a small group of brilliant stars. At first glance these two features could not be more different, but they are in fact closely linked. The cloud contains huge amounts of cool cosmic dust and is a nursery where new stars are being born. It is likely that the Sun formed in a similar star formation region more than four billion years ago.”
“This cloud is known as Lupus 3 and it lies about 600 light-years from Earth in the constellation of Scorpius (The Scorpion). The section shown here is about five light-years across.”
“As the denser parts of such clouds contract under the effects of gravity they heat up and start to shine. At first this radiation is blocked by the dusty clouds and can only be seen by telescopes observing at longer wavelengths than visible light, such as the infrared. But as the stars get hotter and brighter their intense radiation and stellar winds gradually clear the clouds around them until they emerge and can be clearly seen.”
“The bright stars right of the center of this new picture form a perfect example of a small group of such hot young stars. Some of their brilliant blue light is being scattered off the remaining dust around them. The two brightest stars are bright enough to be seen easily with a small telescope or binoculars. They are young stars that have not yet started to shine by nuclear fusion in their cores and are still surrounded by glowing gas. They are probably less than one million years old.”
Even though they remain somewhat obscured at first glance, surveys have located many more very young stellar objects in this area that are not yet clearly visible. This nursery is one of the closest such objects to our solar system, allowing very detailed levels of observation.
“Star formation regions can be huge, such as the Tarantula Nebula where hundreds of massive stars are being formed. However, most of the stars in our and other galaxies are thought to have formed in much more modest regions like the one shown here, where only two bright stars are visible and no very heavy stars are formed. For this reason, the Lupus 3 region is both fascinating for astronomers and a beautiful illustration of the early stages of the life of stars.”
Image Credits: ESO/F. Comeron; ESO/Digitized Sky Survey 2, Acknowledgement: Davide De Martin