The Rosette Nebula, also known as Caldwell 49, is not the only cosmic cloud of gas and dust to evoke the imagery of flowers, but it is the most famous. The petals of this rose are actually a stellar nursery whose lovely, symmetric shape is sculpted by the winds and radiation from its central cluster of hot young stars.
The nebula, a giant molecular cloud in the Monoceros (the Unicorn) region of the Milky Way Galaxy, lies at a distance of some 5,200 light-years from Earth, and measure roughly 130 light years in diameter. The mass of the nebula is estimated to be around 10,000 solar masses.
A survey of the nebula with the Chandra X-ray Observatory in 2001 has revealed the presence of very hot, young stars at the core that lights up the Nebula. The young stars’ radiation excites the atoms in the nebula, causing them to emit radiation themselves producing the emission nebula we see. The central cavity in the Rosette Nebula, cataloged as NGC 2237, is about 50 light-years in diameter. Specific colors of Sulfur (shaded red), Hydrogen (green), and Oxygen (blue), capture the central region in tremendous detail.
This spectacular image shows the hot, bright stars in the center of the cloud heating the gas surrounding them from 100 Kelvins to 10000 Kelvins, increasing the pressure of the gas by more than a hundred times, and causing it to push against the surrounding clouds of gas, simultaneously eating away at them, and compressing them to small, dark compact regions which will become the next generation of stars.
This image made with observations from Herschel’s Photoconductor Array Camera and Spectrometer and the Spectral and Photometric Imaging Receiver instrument from the Herschel Space Observatory shows the clouds associated with the Rosette nebula. Herschel collects the infrared light given out by dust. The bright smudges are dusty cocoons containing massive embryonic stars, which will grow up to 10 times the mass of our sun. The small spots near the center of the image are lower mass stellar embryos. The Rosette nebula itself, and its massive cluster of stars, is located to the right of the picture.
Sources: Hershel Space Observatory, Light Vortex Astronomy, NASA, Sky & Telescope, Space, Wikipedia.