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Posts Tagged ‘NuSTAR

Catching Black Holes on the Fly

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An optical color image of galaxies is seen here overlaid with X-ray data (magenta) from NASA's Nuclear Spectroscopic Telescope Array (NuSTAR). Image credit: NASA/JPL-Caltech

An optical color image of galaxies is seen here overlaid with X-ray data (magenta) from NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR). Image credit: NASA/JPL-Caltech

NASA’s black-hole-hunter spacecraft, the Nuclear Spectroscopic Telescope Array, or NuSTAR, has “bagged” its first 10 supermassive black holes. The mission, which has a mast the length of a school bus, is the first telescope capable of focusing the highest-energy X-ray light into detailed pictures.

The new black-hole finds are the first of hundreds expected from the mission over the next two years. These gargantuan structures — black holes surrounded by thick disks of gas — lie at the hearts of distant galaxies between 0.3 and 11.4 billion light-years from Earth.

“We found the black holes serendipitously,” explained David Alexander, a NuSTAR team member based in the Department of Physics at Durham University in England and lead author of a new study appearing Aug. 20 in the Astrophysical Journal. “We were looking at known targets and spotted the black holes in the background of the images.”

Additional serendipitous finds such as these are expected for the mission. Along with the mission’s more targeted surveys of selected patches of sky, the NuSTAR team plans to comb through hundreds of images taken by the telescope with the goal of finding black holes caught in the background.

Once the 10 black holes were identified, the researchers went through previous data taken by NASA’s Chandra X-ray Observatory and the European Space Agency’s XMM-Newton satellite, two complementary space telescopes that see lower-energy X-ray light. The scientists found that the objects had been detected before. It wasn’t until the NuSTAR observations, however, that they stood out as exceptional, warranting closer inspection.

By combining observations taken across the range of the X-ray spectrum, the astronomers hope to crack unsolved mysteries of black holes. For example, how many of them populate the universe?

“We are getting closer to solving a mystery that began in 1962,” said Alexander. “Back then, astronomers had noted a diffuse X-ray glow in the background of our sky but were unsure of its origin. Now, we know that distant supermassive black holes are sources of this light, but we need NuSTAR to help further detect and understand the black hole populations.”

This X-ray glow, called the cosmic X-ray background, peaks at the high-energy frequencies that NuSTAR is designed to see, so the mission is key to identifying what’s producing the light. NuSTAR can also find the most hidden supermassive black holes, buried by thick walls of gas.

“The highest-energy X-rays can pass right through even significant amounts of dust and gas surrounding the active supermassive black holes,” said Fiona Harrison, a study co-author and the mission’s principal investigator at the California Institute of Technology, Pasadena.

Data from NASA’s Wide-field Infrared Survey Explorer, or WISE, and Spitzer missions also provide missing pieces in the puzzle of black holes by weighing the mass of their host galaxies.

“Our early results show that the more distant supermassive black holes are encased in bigger galaxies,” said Daniel Stern, a co-author of the study and the project scientist for NuSTAR at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “This is to be expected. Back when the universe was younger, there was a lot more action with bigger galaxies colliding, merging and growing.”

Future observations will reveal more about the beastly happenings of black holes, near and far. In addition to hunting remote black holes, NuSTAR is also searching for other exotic objects within our Milky Way galaxy…
… Read more at http://www.jpl.nasa.gov/news/news.php?release=2013-270

Written by physicsgg

September 6, 2013 at 10:36 am

Posted in ASTRONOMY, ASTROPHYSICS

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NASA’s NuSTAR Spots Flare From Milky Way’s Black Hole

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NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, has captured these first, focused views of the supermassive black hole at the heart of our galaxy in high-energy X-ray light. Image credit: NASA/JPL-Caltech

PASADENA, Calif. – NASA’s newest set of X-ray eyes in the sky, the Nuclear Spectroscopic Telescope Array (NuSTAR), has caught its first look at the giant black hole parked at the center of our galaxy. The observations show the typically mild-mannered black hole during the middle of a flare-up.

“We got lucky to have captured an outburst from the black hole during our observing campaign,” said Fiona Harrison, the mission’s principal investigator at the California Institute of Technology (Caltech) in Pasadena. “These data will help us better understand the gentle giant at the heart of our galaxy and why it sometimes flares up for a few hours and then returns to slumber.”

The new images can be seen by visiting: http://www.nasa.gov/nustar .

NuSTAR, launched June 13, is the only telescope capable of producing focused images of the highest-energy X-rays. For two days in July, the telescope teamed up with other observatories to observe Sagittarius A* (pronounced Sagittarius A-star and abbreviated Sgr A*), the name astronomers give to a compact radio source at the center of the Milky Way. Observations show a massive black hole lies at this location. Participating telescopes included NASA’s Chandra X-ray Observatory, which sees lower-energy X-ray light; and the W.M. Keck Observatory atop Mauna Kea in Hawaii, which took infrared images.

These are the first, focused high-energy X-ray views of the area surrounding the supermassive black hole, called Sagittarius A*, at the center of our galaxy. Image credit: NASA/JPL-Caltech

Compared to giant black holes at the centers of other galaxies, Sgr A* is relatively quiet. Active black holes tend to gobble up stars and other fuel around them. Sgr A* is thought only to nibble or not eat at all, a process that is not fully understood. When black holes consume fuel — whether a star, a gas cloud or, as recent Chandra observations have suggested, even an asteroid — they erupt with extra energy.

In the case of NuSTAR, its state-of-the-art telescope is picking up X-rays emitted by consumed matter being heated up to about 180 million degrees Fahrenheit (100 million degrees Celsius) and originating from regions where particles are boosted very close to the speed of light. Astronomers say these NuSTAR data, when combined with the simultaneous observations taken at other wavelengths, will help them better understand the physics of how black holes snack and grow in size.

“Astronomers have long speculated that the black hole’s snacking should produce copious hard X-rays, but NuSTAR is the first telescope with sufficient sensitivity to actually detect them,” said NuSTAR team member Chuck Hailey of Columbia University in New York City.

Read more: www.nasa.gov

Written by physicsgg

October 23, 2012 at 8:38 pm

Posted in ASTRONOMY, ASTROPHYSICS

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How NASA’s NuSTAR Spacecraft Will Hunt Black Holes

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Written by physicsgg

June 11, 2012 at 10:42 am

Posted in ASTRONOMY, ASTROPHYSICS, COSMOLOGY, SPACE

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