FOR THE FIRST TIME, WE SEE A STAR WE KNOW IS DEAD
My dear friend, the eminent Armenian astronomer Garik Israelian, is part of a team which has just published a unique and quite amazing discovery.
They have, by comparing observations made over many years, identified a particular kind of star in a particular phase of its life, and are able to say with some confidence that, although we and our descendants will be able to see the star shining in our skies for at least hundreds of years to come, it probably no longer exists.
Here is what Garik says :
For the first time, we see a star which most probably (99%) does not exist now, in our time.
The star HR8752 is few thousand light years from us, so we are seeing it as it was a few thousand years ago.
I have estimated that when the stellar light corresponding to its present state reaches us, this star will be seen to have exploded as Supernova. Our observations indicate spectacular changes in the internal structure: the star is losing 1 solar mass every year !!! And its current mass is less than 20 solar masses. It will not “expire” in 20 years, but in less than 1000 years it will evolve so fast that the ONLY final solution for the star will be a Supernova explosion.
Attention! My statement (that we are looking at a star which does not exist NOW) does not apply to any other known stars in the Galaxy – no matter how far away they are. More than 99% of the galactic stars are stable enough that we can be sure that they are still there – they exist NOW.
Of course you may say “what about very distant galaxies, 10 billion light years away? The universe is less than 14 billion years old, so maybe those far away galaxies do not exist anymore?” Again, the answer is “They DO exist today”.
The star HR8752 is dead. It has become a black hole of a few solar masses – ie – with a mass a few times that of our Sun.
I will ask Garik for a picture of this star.