Wolf-Rayet throws a few cosmic tantrums
WR 136 (Wolf-Rayet 136) was born about 4 to 5 million years ago when a cloud of gas and dust collapsed to form a very massive star.
At 21 times the mass and a whopping 600,000 times the brilliance of our sun, WR 136 is easily detectable even at its vast distance from us at 6,700 light years.
The problem with such gigantic stars is they are very unstable. Since its birth, WR 136 has been throwing cosmic tantrums, which discharged large amounts of gas off its surface. As the hydrogen gas core fused into helium and heavier elements, WR 136 grew to a bloated red giant and began what I call the “stellar indigestion” stage of its life. This stage began when modern humans first walked the Earth about 100,000 to 200,000 years ago.
At its red giant phase, WR 136 increased the intensity, amount and speed of the gas and radiation that it spewed into space. That extra energy caught up with and lit up the gaseous shell it discharged over the eons since its birth. That’s what you see here.
The shell of primarily energized hydrogen and oxygen is near 100 light years wide at its widest point. It is cataloged as NGC 6888 and named the Crescent Nebula. I like to visualize it as a half clam shell with WR 136 being the pearl embedded near its center.
The other stars in this image are not associated with the Crescent Nebula. This nebula is near the center of the constellation Cygnus the Swan, also known as the Northern Cross, best seen during the summer months. Cygnus “flies” through the band of the Milky Way which adorns this region with an abundance of stars. That’s why you see so many stars almost blotting out the darkness of interstellar space.
Another stupendous phase is in store for WR 136 when it uses up the hydrogen “fuel” in its core. When the core fuses to iron, WR
136 will be unable to sustain nuclear fusion and will quickly and catastrophically collapse, causing a supernova.
The unimaginably intense explosion will obliterate the Crescent Nebula and replace it with a supernova remnant with a neutron star or a black hole at its center.
Gary Zientara owns and operates Mount Sangre Observatory in Angel Fire.