NASA may have just improved our potential for deep space exploration by inventing a new type of autonomous space navigation. Known as Station Explorer for X-Ray Timing and Navigation Technology, or SEXTANT, the technology uses pulsars — rotating neutron stars that emit electromagnetic radiation — to determine the location of objects in space.
The way SEXTANT uses pulsars has been compared to how GPS navigation can provide drivers with positioning and accurate navigation using satellites orbiting around Earth. The pulsars SEXTANT uses are best observed in the X-ray spectrum, in which their beams of radiation essentially turn them into lighthouses.
via Futurism
more info at NASA
https://gameon.nasa.gov/projects/deep-space-x-ray-navigation-and-communication/