These clouds prevent telescopes from seeing the black holes within, but NuSTAR found them by detecting high-energy X-rays which penetrates the clouds.
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Iain Hannah, of the University of Glasgow, Scotland, presented the image today at the Royal Astronomical Society’s National Astronomy meeting in Llandudno, Wales.
Hannah said, “Our sun is quietening down in its activity cycle, but still has a couple of years before it reaches a minimum”.
But it can also collect X-ray images of our own sun in unprecedented detail. Astronomers from Durham University in the United Kingdom used NASA’s Nuclear Spectroscopic Telescope Array to find the five “secluded beasts”, NASA reported. The X-ray activity it captured is seen in blue and is equal to between two and six kiloelectron volts, while low-energy X-rays of between 0.2 to 2.4 kiloelectron volts were captured by Japan’s Hinode spacecraft and are visible in green. Most galaxies are thought to harbor giant, or “supermassive” black holes at their cores.The astronomers pointed the telescope at nine suspected, hidden supermassive black holes that were thought to be feasting on material at the centre of galaxies, but where shrouds of gas and dust might be obscuring some of the activity.In five cases, releases of high-energy x-rays confirmed the presence of black holes, the researchers said. They occur when magnetic field lines become tangled and broken, and then reconnect. But it can help measure the energy of smaller microflares, which produce only one-millionth of the energy of the larger flares. Put simply, the corona is too hot; the tenuous plasma that extends from the sun’s photosphere (colloquially known as the sun’s “surface”) can be millions of degrees Kelvin (Celsius) hotter than the sun’s uppermost layers.
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NuSTAR is a Small Explorer mission led by the California Institute of Technology in Pasadena and managed by NASA’s Jet Propulsion Laboratory, also in Pasadena, for NASA’s Science Mission Directorate in Washington. As the electrons zip around, they give off high-energy X-rays. The composite image shows the sun’s flaring, active regions. While scientists know that energy is generally liberated in the upper solar atmosphere, the locations and detailed mechanisms aren’t precisely known.
