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Astronomers Discover 33 Pairs of Waltzing Black Holes 101

Astronomers from UC Berkeley have identified 33 pairs of waltzing black holes, closing the gap somewhat between the observed population of super-massive black hole pairs and what had been predicted by theory. "Astronomical observations have shown that 1) nearly every galaxy has a central super-massive black hole (with a mass of a million to a billion times the mass of the Sun), and 2) galaxies commonly collide and merge to form new, more massive galaxies. As a consequence of these two observations, a merger between two galaxies should bring two super-massive black holes to the new, more massive galaxy formed from the merger. The two black holes gradually in-spiral toward the center of this galaxy, engaging in a gravitational tug-of-war with the surrounding stars. The result is a black hole dance, choreographed by Newton himself. Such a dance is expected to occur in our own Milky Way Galaxy in about 3 billion years, when it collides with the Andromeda Galaxy."

The Perfect Way To Slice a Pizza 282

iamapizza writes "New Scientist reports on the quest of two math boffins for the perfect way to slice a pizza. It's an interesting and in-depth article; 'The problem that bothered them was this. Suppose the harried waiter cuts the pizza off-center, but with all the edge-to-edge cuts crossing at a single point, and with the same angle between adjacent cuts. The off-center cuts mean the slices will not all be the same size, so if two people take turns to take neighboring slices, will they get equal shares by the time they have gone right round the pizza — and if not, who will get more?' This is useful, of course, if you're familiar with the concept of 'sharing' a pizza."

Yellowstone Supervolcano Larger Than First Thought 451

drewtheman writes "New studies of the plumbing that feeds the Yellowstone supervolcano in Wyoming's Yellowstone National Park shows the plume and the magma chamber under the volcano are larger than first thought and contradicts claims that only shallow hot rock exists. University of Utah research professor of geophysics Robert Smith led four separate studies that verify a plume of hot and molten rock at least 410 miles deep that rises at an angle from the northwest."

Comment Re:about time... (Score 1) 203

I'd like to see a REAL color photograph at some point and not something they recolored after...
and real video footage as opposed to footage put together from still images

There's no such thing as "real color photography" actually. Any color camera only approximates the color you see with your eyes, even old film cameras. Pick up any decent book and photography and you'll see mention of using filters to make things look more natural. With CCD cameras you're only counting photons. The detector itself can't tell a red photon from a blue photon, and it relies on an arrangement of band pass filters so that individual cells collect only a certain color range. So your point and shoot color CCD camera is like multiple black & white cameras with different color filters. The Wide Angle Camera (WAC) on LRO has 5 visual band filters and 2 ultraviolet band filters. They bands can be put together to give a "color" image. Even when you look at one of these color images you'll still see the gray Moon, so it's not very exciting visually. However, the response at different frequencies is very useful to scientists in determining properties of the imaged area.

As for video footage... egads! Nevermind that "real video" actually IS a series of still images, we have a firehose of data to deal with right now!


Submission + - First Apollo Images From LROC (

bsdphx writes: LROC, the camera suite aboard NASA's Lunar Reconnaissance Orbiter has taken it's first images of Apollo landing sites. Image resolution is from 1.0 to 1.4 meters per pixel and includes zoomable, scrollable images of the sites of Apollo 11, Apollo 14, Apollo 15, Apollo 16, and Apollo 17. These are only the first of many images to come, and as LRO reaches its nominal orbit we will see resolutions of approx. 0.5 meters per pixel!
GNU is Not Unix

Submission + - RMS Encouraging Commerical Software Usage? (

bsdphx writes: Does Richard Stallman play by the same rules that he expects others to play by? Apparently he's been speaking off the cuff without researching the things he's talking about, which has lead to his not recommending some Free Software while listing other non-Free software as good for your soul. This might fly for a while in some places, but taking this to the OpenBSD community was sure to get rms called out, and he's not holding up his side of the argument very well.

Submission + - Theo de Raadt Explains License Modification (

Ray Lai writes: "Theo de Raadt explains the legal ramifications of changing code licenses:

It is illegal to modify a license unless you are the owner/author, because it is a legal document. If there are multiple owners/authors, they must all agree. A person who receives the file under two licenses can use the file in either way.... but if they distribute the file (modified or unmodified!), they must distribute it with the existing license intact, because the licenses we all use have statements which say that the license may not be removed.

Operating Systems

Submission + - Linux Driver Violates BSD License (

bsdphx writes: After years of encouragement from the OpenBSD community for others to use Reyk Floeter's free atheros wireless driver, it seems that the Linux world is finally listening. Unfortunately, they seem to think that they can strip the BSD license right out of it.

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