The first image of the sun captured by NASA’s Spectroscopic Telescope Array (NuSTAR), which sensitive to high-energy X-ray light. X-rays seen by NuSTAR show up as green and blue in the , which is overlaid on an image taken by NASA’s Solar Dynamics Observatory.

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A NASA space telescope designed to peer at faraway black holes has snapped a stunning image of the sun, showing that its sensitive X-ray eyes can investigate mysteries in Earth’s own neighborhood.
The new image, which was taken by NASA’s NuSTAR spacecraft (short for Nuclear Spectroscopic Telescope Array), is the best-ever of the sun in high-energy X-ray light, space agency officials said. The photo, and others taken by NuSTAR in the , should researchers learn more about our star, they added.

“NuSTAR will give us a unique look at the sun, from the to the highest parts of its atmosphere,” NuSTAR team member David Smith, of the , Santa Cruz, said in a statement. 
The new image, which was released Monday (Dec. 22), overlays NuSTAR observations (seen in blue and green) onto an image of the sun captured by NASA’s Solar Dynamics Observatory spacecraft.
NuSTAR solar observations might also more about the nature of dark matter, the mysterious stuff thought to make up most of the universe.
Dark matter does not emit or absorb light — hence its name — and nobody knows for sure what it’s made of. A number of exotic particles have been proposed as dark matter constituents, including weakly interacting massive particles, sterile neutrinos and axions.
If axions exist, NuSTAR may see signs of them — patches of X-rays in the center of the sun — NASA officials said.