Two supermassive black holes on collision course...

metavac · Post by **metavac** » 2007-05-22 08:47pm

...of course, we'll all be long dead and gone by the time it happens. Includes link to article at Science (free abstract and material and methods supplement).

Patrick Degan · Post by **Patrick Degan** » 2007-05-22 10:43pm

Well, in point of fact, the collision has already happened 300 million years ago. We won't see the actual show from Earth for another 3000 years yet.

metavac · Post by **metavac** » 2007-05-22 11:36pm

The article says the collision will occur over the course of a 'a few hundred million years.' I've seen other sources claim spiral 10 to 100 million years, although that's not reflected in any of the press releases.

Patrick Degan · Post by **Patrick Degan** » 2007-05-22 11:48pm

Point taken. But we're still essentially seeing the ghost of an event that's already happened. Such are the fascinating effects of relativity and distance.

Why bother with the "supernatural" when the real universe produces infinitely more spectacular phenomena which far outstrip any faery tale?

metavac · Post by **metavac** » 2007-05-23 12:03am

Patrick Degan wrote:Point taken. But we're still essentially seeing the ghost of an event that's already happened. Such are the fascinating effects of relativity and distance.

That's my point. It might not have happened yet. Unfortunately, I'm not paying $10 to read the article and I can't find an e-print on the issue. What we're seeing is 300 million years old, yes, but that doesn't mean the event has entered into the future light cone of any position in space-time yet. As indicated here, at 3000 ly with a velocity difference of 20 km/s, we're seeing light from very early on in merger.

Ariphaos · Post by **Ariphaos** » 2007-05-23 05:45am

Patrick Degan wrote:Well, in point of fact, the collision has already happened 300 million years ago. We won't see the actual show from Earth for another 3000 years yet.

They're 3,000 light-years apart. They aren't approaching eachother at a speed anywhere close to that of light and are likely only to collide through gravitational rotation as their orbits get tighter. It will likely take billions, if not trillions of years.

Lord of the Abyss · Post by **Lord of the Abyss** » 2007-05-23 06:47am

Patrick Degan wrote:Why bother with the "supernatural" when the real universe produces infinitely more spectacular phenomena which far outstrip any faery tale?

Since you asked; I think a lot of the attraction so many feel for the supernatural is the human scale of most of it. There are plenty of impressive things in science, but they tend to be too big or too fast or too slow or too large or otherwise beyond the normal human realm of experience ( or survival ). They also tend to be impersonal, or when they do relate to humans, disturbing ( like brain research ).

Black hole collisions are far grander than spoon bending and faith healing, and have the advantage of not being frauds; they are also happen very far away, on a scale of space and time that are simply beyond a human's direct experience. And unlike gods or spirits, they don't care in the slightest about us.