Hot, massive stars illuminate billowing clouds of gas and dust in this view of NGC 2264, a stellar nursery in Monoceros, the unicorn. Radiation and winds from the bright star at the top of the image, S Monocerotis, have carved a bubble in the nebula. Radiation from S Monocerotis and other stars causes hydrogen gas in the cloud to glow. Another bright star is eroding a tight knot of gas and dust, creating the cone-shaped structure known as the Cone Nebula. NGC 2264 has given birth to hundreds of stars, with many more still taking shape. [ESO]
To the eye alone, the space between the bright stars Procyon and Betelgeuse looks pretty empty. Unless you’re under a dark country sky, in fact, there’s not much to see there at all.
In reality, though, that region of the sky contains a busy stellar nursery — a giant cloud of gas and dust that’s given birth to many stars, and is forming others even now.
The most prominent part of the nursery is NGC 2264, which is about 2500 light-years from Earth. It consists of a cluster of hot, bright stars that’s surrounded by filaments of glowing hydrogen gas.
The main star system in the cluster is known as S Monocerotis, for the constellation Monoceros, the unicorn. It actually consists of two stars that are among the youngest, hottest, and most massive in our part of the galaxy. The surrounding clouds of gas and dust reflect light from this system, so they look blue.
The stars of S Monocerotis also produce enormous amounts of ultraviolet energy. The UV zaps clouds of hydrogen gas across dozens of light-years, causing the gas to glow like a fluorescent bulb. Winds from the system blast away some of the gas and dust like a stellar blowtorch. That prevents the gas around S Monocerotis from coalescing to form new stars.
New stars are being born farther away from S Monocerotis and its bright siblings. Some of them may be forming inside a dark cloud with one of the most distinctive shapes in all the night sky: the Cone Nebula. More about that tomorrow.
Script by Damond Benningfield, Copyright 2014
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