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View Full Version : Black Hole Gonna Get Me - Bad Astronomy



Squink
2009-Dec-14, 02:52 PM
At Science Daily:
Black Hole Found to Be Much Closer to Earth Than Previously Thought (http://www.sciencedaily.com/releases/2009/12/091209193904.htm#)
An international team of astronomers has accurately measured the distance from Earth to a black hole for the first time. Without needing to rely on mathematical models the astronomers came up with a distance of 7800 light years, much closer than had been assumed until now.
Apparently they got a new distance for V404 Cygni from parallax data obtained with multiple radio telescopes over the course of a year.
2400 parsecs is, as far as I know, a little far for conventional parallax measurements to work well, but the article glosses over that and focuses on how the black hole is potentially even scarier than previously thought?

George
2009-Dec-14, 05:37 PM
The improvement in the parallax comes from the higher resolution capability of the High Sensitivity Array. This still gives them a margin of error of 6%, apparently.

This does seem a little better than the Hipparcos accuracy, but not by leaps and bounds.

Hornblower
2009-Dec-14, 06:24 PM
At Science Daily:
Black Hole Found to Be Much Closer to Earth Than Previously Thought (http://www.sciencedaily.com/releases/2009/12/091209193904.htm#)
Apparently they got a new distance for V404 Cygni from parallax data obtained with multiple radio telescopes over the course of a year.
2400 parsecs is, as far as I know, a little far for conventional parallax measurements to work well, but the article glosses over that and focuses on how the black hole is potentially even scarier than previously thought?

Where in that article, if anywhere, is there any mention of its being scary?

Squink
2009-Dec-14, 06:32 PM
I was scared. The thing is like ninja kitty, we looked away for a moment, and its distance was halved when we looked back.
The newsworthy deal isn't that it's closer than previously thought, it's that they figured a better way to measure the distance. That got buried nicely under the OMG it's teh closer schtick.

neilzero
2009-Dec-24, 11:48 PM
Even if it is approaching at one parsec per century. we can wait 240,000 years to panic. Likely it approaching at a much slower speed. Neil