Hanging On

StarDate

A star in Cassiopeia refuses to die. If astronomers are correct, it was “born” from the merger of two corpses. Such a collision usually blasts both stars to bits, but not this time. The combined star survived – also as a corpse. But it may not be completely dead. It’s producing a strong wind – a sign of possible rejuvenation.

The star appears to be the remnant of a supernova that was seen in the year 1181. It remained visible for six months.

The supernova may have formed from the merger of two white dwarfs – dead stars that are the final act for stars like the Sun. In most cases, such a merger makes the combined stars too massive to survive. The merged object blasts itself to cosmic dust.

In this case, though, only a fraction of the mass of the two stars was blasted away. The rest formed a white dwarf heavier than the Sun. It’s the hottest star yet seen – hundreds of thousands of degrees hotter than the Sun.

A recent study showed that the star is blowing a “wind” of particles into space at about five percent of the speed of light. The types of particles indicate that nuclear fusion has fired up in a thin layer around the core of the white dwarf – new life for a star that refuses to die.

Cassiopeia is in the northeast at nightfall. It looks like a sideways letter W. The possible supernova remnant is near the tip of the bottom left point of the W – about 7500 light-years away.

Script by Damond Benningfield