. Medical and Hospital News .




STELLAR CHEMISTRY
The Diner at the Center of the Galaxy
by Staff Writers
Los Angeles CA (SPX) Nov 28, 2012


A new ScienceCast video explores the Milky Way's central black hole.

Deep in the heart of the spiral Milky Way galaxy, a hot vortex of matter swirls around a black hole more than a million times as massive as the sun. Many galaxies, perhaps all, contain such a "monster in the middle."

These supermassive black holes sustain themselves by swallowing stars, planets, asteroids, comets and clouds of gas that wander by the crowded galactic core.

NASA's NuSTAR spacecraft recently caught the Milky Way's central black hole in the act of having a snack.

"We got lucky and captured an outburst from the black hole during our [first] observing campaign," says Fiona Harrison, the mission's principal investigator at the California Institute of Technology.

NuSTAR is an orbiting observatory designed to take pictures of violent, high-energy phenomena in the universe. Launched on June 13, 2012, it is the only telescope capable of producing focused images of the highest-energy X-rays produced by dying stars and ravenous black holes.

"It's like putting on a new pair of glasses and seeing aspects of the world around us clearly for the first time," says Harrison.

NuSTAR's first light image of Cygnus X-1, a black hole in our galaxy that is siphoning gas off a giant-star companion, shows what she's talking about: click here

NuSTAR's sharp vision allowed it to pinpoint a burst of hard X-rays coming from the galactic center during an observing campaign in July. Lower-energy X-ray observations by NASA's Chandra X-ray Observatory and infrared data from the Keck telescope in Hawaii confirmed the outburst. The Milky Way's black hole had just swallowed ... something.

Black hole snacks are a violent process in which the "meal" is ripped apart by powerful tides and heated to millions of degrees as it slides down the gullet of the gravitational singularity. In this case, NuSTAR picked up X-rays emitted by matter being heated up to about 100 million degrees Celsius.

The observation raises hopes that astronomers will be able to solve a long-standing mystery: Why is the Milky Way's supermassive black hole such a picky eater?

Compared to giant black holes at the centers of other galaxies, the Milky Way's is relatively quiet. More active black holes tend to gobble up matter in prodigious quantities. Ours, on the other hand, is thought only to nibble or not eat at all.

Asteroids could be a primary food source. One model holds that trillions of asteroids surround the Milky Way's core. Astronomers using the Chandra X-ray Observatory have indeed detected flares consistent with asteroids 10 km wide or larger falling into the black hole.

These space rocks would be about the same size as the asteroid that wiped out the dinosaurs on Earth 65 million years ago. Smaller space rocks might be falling in, too, but their flares would be too weak for Chandra to detect.

NuSTAR brings something new to the problem. With its unprecedented ability to detect and make focused images of X-ray flares, the telescope will almost certainly help astronomers understand what's happening deep in the core of our galaxy. The monster's menu might soon be revealed.

For more information about NuSTAR and its focused observations of black holes, visit the mission's home page here

.


Related Links
NuSTAR
Stellar Chemistry, The Universe And All Within It






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review

Newsletters :: SpaceDaily Express :: SpaceWar Express :: TerraDaily Express :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

Get Our Free Newsletters
Space - Defense - Environment - Energy - Solar - Nuclear

...





STELLAR CHEMISTRY
Failed explosions explain most peculiar supernovae
Chicago IL (SPX) Nov 23, 2012
Supercomputer simulations have revealed that a type of oddly dim, exploding star is probably a class of duds-one that could nonetheless throw new light on the mysterious nature of dark energy. Most of the thousands of exploding stars classified as type Ia supernovae look similar, which is why astrophysicists use them as accurate cosmic distance indicators. They have shown that the expansio ... read more


STELLAR CHEMISTRY
Chernobyl shelter construction reaches key landmark

CCNY Landscape Architect Offers Storm Surge Defense Alternatives

Sandy costs top $42 bn in New York: governor

Haitian president talks quake relief with Pope Benedict XVI

STELLAR CHEMISTRY
GTX Gets Approval For Custom Two-Way GPS Tracking Devices On Planes

East Riding Of Yorkshire Council Selects Ctrack For Specialist Vehicle Tracking Solution

Researchers Use GPS Tracking to Monitor Crab Behavior

US Navy, Raytheon receive Pentagon engineering award for GPS-guided precision landing program

STELLAR CHEMISTRY
A 3-D light switch for the brain

Scientists improve dating of early human settlement

Oldest home in Scotland unearthed

Archaeologists identify spear tips used in hunting a half-million years ago

STELLAR CHEMISTRY
Uncovering complexity

Process for chameleon-like changes in abundant phytoplankton uncovered

Bitsy beetle warms Canada: study

Probing the mystery of the Venus fly trap's botanical bite

STELLAR CHEMISTRY
Nearly half a million Arabs HIV-infected: UN

This week's forecast: Sunny with a 40 percent chance of flu

Yellow fever-hit Darfur gets help from US Navy

New strain of bird virus sweeps across Britain

STELLAR CHEMISTRY
Chinese insurer hits out at Wen Jiabao report

Four more Tibetans set themselves alight in China

Tibetan self-immolates in northwest China

Record numbers flock to take Chinese government test

STELLAR CHEMISTRY
Four Chinese hostages freed in Colombia

Piracy will swell again if seas not policed: S.African Navy

Mekong River attackers get death sentences

West African pirates target oil tankers

STELLAR CHEMISTRY
Tokyo eyes $10.7 bln stimulus ahead of polls: reports

Walker's World: UK survives EU budget row

China manufacturing grows in November: HSBC

Reforms needed for China growth: premier-to-be Li




The content herein, unless otherwise known to be public domain, are Copyright 1995-2012 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement