NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, set its X-ray eyes on a spiral galaxy and caught the brilliant glow of two black holes lurking inside.
"These new images showcase why NuSTAR is giving us an unprecedented look at the cosmos", said Lou Kaluzienski, NuSTAR program scientist at NASA headquarters in Washington. "With NuSTAR's greater sensitivity and imaging capability, we're getting a wealth of new information on a wide array of cosmic phenomena in the high-energy X-ray portion of the electromagnetic spectrum".
Launched last june, NuSTAR is the first orbiting telescope with the ability to focus high-energy X-ray light. It can view objects in considerably greater detail than previous missions operating at similar wavelengths.
The mission has looked at a range of extreme, high-energy objects already, including black holes near and far, and the incredibly dense cores of dead stars. In addition, NuSTAR has begun black hole searches in the inner region of the Milky Way galaxy and in distant galaxies in the universe.
Among the telescope's targets is the spiral galaxy IC342, also known as Caldwell 5. This galaxy lies 7 million light-years away in the constellation Camelopardalis (the Giraffe). Previous X-ray observations of the galaxy from NASA's Chandra X-ray Observatory revealed the presence of two blinding black holes, called ultraluminous X-ray sources (ULXs).
How ULXs can shine so brilliantly is an ongoing mystery in astronomy. While these black holes are not as powerful as the supermassive black hole at the hearts of galaxies, they are more than 10 times brighter than the stellar-mass black holes peppered among the stars in our own galaxy. Astronomers think ULXs could be less common intermediate-mass black holes, with a few thousand times the mass of our sun, or smaller stellar-mass black holes in an unusually bright state. A third possibility is that these black holes don't fit neatly into either category.
"High-energy X-rays hold a key to unlocking the mystery surrounding these objects", said Fiona Harrison, NuSTAR principal investigator at the California Institute of Technology in Pasadena. "Whether they are massive black holes, or there is new physics in how they feed, the answer is going to be fascinating".
In the image, the two bright spots that appear entangled in the arms of the IC342 galaxy are the black holes. High-energy X-ray light has been translated into the color magenta, while the galaxy itself is shown in visible light.
"Before NuSTAR, high-energy X-ray pictures of this galaxy and the two black holes would be so fuzzy that everything would appear as one pixel", said Harrison.
NuSTAR is a Small Explorer mission led by Caltech and managed by NASA's Jet Propulsion Laboratory in Pasadena for NASA's Science Mission Directorate in Washington.
NuSTAR's mission operations center is at UC Berkeley, with the Italian Space Agency providing an equatorial ground station located at Malindi, Kenya. The mission's outreach program is based at Sonoma State University in Rohnert Park, Calif. Goddard manages NASA's Explorer Program. Caltech manages JPL for NASA. login to comment or register