Milky Way's Black Hole Wasn't Always Such a Wimp 83
scibri writes "Sagittarius A*, the dormant supermassive black hole that lies at the center of our galaxy, was much more active not that long ago. Astronomers using the Fermi Gamma-ray Space Telescope have picked up some faint gamma-ray signals that suggest Sagittarius A* was emitting a pair of powerful gamma-ray jets like other galactic black holes as recently as 20,000 years ago (arXiv paper). If our black hole was more active in the past, it could explain why Sagittarius A* seems to be growing about 1,000 times too slowly for it to have reached its current mass of about four million solar masses since the Galaxy formed about 13.2 billion years ago."
Re:Weight of a teaspoon amount (Score:5, Insightful)
Re:Weight of a teaspoon amount (Score:3, Insightful)
> The singularity itself? A teaspoon of singularities would have infinite weight.
No, it wouldn't. Black holes have a finite weight.
Singularities consume no space, so you can fit an infinite number of finite weight singularities in a teaspoon. Hence infinite weight
Re:WWKKT? What would Kim K. think? (Score:5, Insightful)
Is anyone else disturbed that such an incredibly major change happened only 20,000 years ago?
This could be worse than an ice age.
No. If, 20,000 years ago, it was much more active, it proves living in a galaxy with an active nucleus is not a problem. What it means is, if it becomes more active again, we don't really have anything to worry about -- we've been living with the "problem" for most of five billion years and gotten along just fine...