… and Back Again
The process of stardeath is one of those events that is not just the end of a star’s life, but possibly the beginning of another one’s existence. In some regions of our galaxy (and in many other galaxies), the explosion of a massive star in an event called a supernova, not only ejects material from the star that will eventually be recycled into other stars. It also sends shock waves through space that can compress nearby nebulae (clouds of gas and dust). That “ripple effect” starts the nebula down the path to star formation as the material begins to coalesce, heat up, and eventually “turn on” in the process of star birth. If the birth cloud has enough heavy elements to form planets, and the conditions are right, the stellar babies could also be born with worlds of their own. This is what happened to create our Sun and planets, more than 4.5 billion years ago.
The image above is a scene of violent stellar destruction, lit up by strong ionizing radiation (UV light) from nearby newborn stars. It’s a star-forming region in the Milky Way called RCW 57, and the nebula itself (the glowing, loop-filled cloud of gas and dust) is called NGC 3582. Some of the stars forming in regions like NGC 3582 are much heavier than the Sun. These monster stars emit energy at prodigious rates and have very short lives that end in supernova explosions. The material ejected from these dramatic events creates bubbles in the surrounding gas and dust. This is the probable cause of the loops visible in this picture. When the stellar beacons that are heating up this cloud start to die they will also send out clouds of gas and dust like these, and the forces of their deaths may well send the clouds back through a cycle of star birth, creating new stars that will light up the death-clouds of their forebears.
The image was processed by the European Southern Observatory (ESO), using observational data identified by Joe DePasquale, from the United States, who participated in ESO’s Hidden Treasures 2010 astrophotography competition. The activity was organised by ESO in October–November 2010, for everyone who enjoys making beautiful images of the night sky using astronomical data obtained using professional telescopes.