NASA peers deep into the cosmos at the bright, leftover cinders of exploded stars, called pulsars.

Now, the space agency has released a map-like image showing loops and arcs of X-ray energy — invisible to the naked eye — radiating from these dense cores of once massive stars.

The most radiant spots are the suspected pulsars, repeatedly blasting X-ray energy into space. These trails of energy, or electromagnetic radiation, reveal the powerful sources of these X-rays.

"Even with minimal processing, this image reveals the Cygnus Loop, a supernova remnant about 90 light-years across and thought to be 5,000 to 8,000 years old,” said NASA's Keith Gendreau, who leads the imaging mission called NICER, in a statement. “We’re gradually building up a new X-ray image of the whole sky, and it’s possible NICER’s nighttime sweeps will uncover previously unknown sources.”

Locations of pulsars.

Image: nasa / nicer

NICER, short for Neutron star Interior Composition Explorer, is a cube-shaped instrument attached to the International Space Station (ISS). NASA focuses on specific pulsar targets, so NICER repeatedly follows similar tracks through the sky, ultimately creating prominent arcs of X-ray radiation on this sky map.

In total, this image is an X-ray map showing 22 months of radiation traveling through space.

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NICER will continue to scan the cosmos for blasts of X-rays so they can better understand the sources of this energy — pulsars. Astronomers suspect these stars act like lighthouse beacons in the universe, regularly emanating or "pulsing" blasts of X-ray light as they spin.

Grasping how different pulsars "pulse" may serve quite useful for future deep space travel through the solar system. NASA plans for a coherent map of pulsars to essentially act like a "GPS system in space."

"When mature, this technology will enable spacecraft to navigate themselves throughout the solar system — and beyond," NASA said.