Recent Posts

Sunday, August 16, 2009

Black Hole Shadow: Very Large Telescope Zaps the Sky

Image of the Day: Laser Strikes at Supermassive Black Hole at Core of the Milky Way Galaxy

It's not the sequel to War of the Worlds! Astronomers at the Very Large Telescope (VLT) site in Chile are trying to measure the distortions of Earth's ever changing atmosphere. Constant imaging of high-altitude atoms excited by the laser -- which appear like an artificial star -- allow astronomers to instantly measure atmospheric blurring. In this case, the VLT was observing our Galaxy's center, and so Earth's atmospheric blurring in that direction was needed.

At the center of the Milky Way is Sagittarius A -believed to be a supermassive black hole, which lurk at the center of all spiral galaxies. If we can observe Sagittarius A*'s surroundings we can confirm once and for all whether it's a black hole - and prove Einstein right (or wrong!) . Relativity theory predicts the existence of black holes. If relativity breaks down, we might not see a black hole at all, but something totally weird.

Relativity describes how large masses can bend space, and a black hole is where the mass is so large that space gives up altogether and becomes a singularity. Black holes are already well understood, we think, but we've only ever observed them at second hand - the behavior of orbiting objects or bent light rays. To actually view the shadow of a black hole, the cut-off point where light is swallowed and cannot escape, would be a massive advance - and only the beginning.
Technorati Tags: , , ,

Powered by ScribeFire.

Philadelphia, MS: Suspect in 1964 Civil Rights Worker Killing Dies

Suspect In 1964 Civil Rights Worker Killings Dies - CBS News
Federal authorities will continue to investigate the 1964 Mississippi killings of three civil rights workers _ a case that helped pass landmark legislation _ despite the death of a key suspect, the Justice Department says.

Billy Wayne Posey, 73, died Thursday. Federal investigators were looking into his possible involvement in the June 21, 1964, killings of James Chaney, Andrew Goodman and Michael Schwerner, who had been working to register black voters.

Posey's funeral was Saturday in Philadelphia, Miss., the town at the heart of the case.

On Friday afternoon, Alejandro Miyar, a spokesman for the Justice Department, said the death does not "alter our cold-case investigation." He said federal authorities are assisting state investigators who could bring state charges.

Goodman's brother, David Goodman, of New York City, said, "This is still the country of law and order, and the laws are clear. There is no statute of limitations on murder."
Technorati Tags: , , , ,

Powered by ScribeFire.

View of the French Market, New Orleans, Late 19th Century

The Old French Market | Shorpy Photo Archive

Circa 1880s-1890s. "The old French Market, New Orleans." Photo by William Henry Jackson. Detroit Publishing Co. glass negative.
Technorati Tags: , , ,

Powered by ScribeFire.