Galactic black holes may be more massive than thought

Who would have imagined that a black hole could be more massive than a thought? (Of course, the headline merely exemplifies the clichéd thinking habits of the unfortunate people who have to write headlines.)

But anyhow, it's an interesting story:

Galactic black holes may be more massive than thought (6/8/09)

Astronomers report that some of the biggest supermassive black holes in nearby galaxies are at least twice and possibly four times as heavy as previously estimated. The findings come from new simulations by two independent teams of researchers, as well as new observations of stars whipping around a handful of supermassive black holes at the centers of massive galaxies no more than a few hundred million light-years from Earth.

Another meta-comment on the story is that people always seem to be fascinated by size. But whatever.

However, the story actually is important for reasons that might not be immediately obvious. The calculations involved took into account the effects of dark matter. And if the work is valid, it could help solve other problems:

“It’s high time that someone included the effect of dark matter,” said John Kormendy of the University of Texas, not a member of Gebhardt’s team. The revised mass estimates, he said, “will have a welcome audience.” That’s because for more than 25 years it has been a puzzle why the most luminous distant quasars are powered by black holes weighing the equivalent of 10 billion solar masses, yet no nearby black holes appear to be this hefty.

More:

A Real Whopper: Black Hole Is Most Massive Known (6/8/09) – Space.com

Black Holes Have Been Underestimated (6/9/09) – ScienceNOW

Most Massive Black Holes Heavier Than Thought (6/9/09) – National Geographic

Computer Finds Massive Black Hole in Nearby Galaxy (6/9/09) – press release

Giant black holes just got bigger (6/9/09) – BBC

Black holes are bigger than we thought (6/11/09) – Cosmos


Update 12/26/10:

More references:

The Black Hole Mass, Stellar M/L, and Dark Halo in M87 (6/17/09) – arXiv.org version

The Black Hole Mass, Stellar M/L, and Dark Halo in M87 (7/16/09) – published article at The Astrophysical Journal

How To See a Black Hole (10/25/09) – Sky and Telescope