The remnants of a collapsed neutron star, called a pulsar, are magnetically charged and spinning anywhere from one rotation per second to hundreds of rotations per second. These celestial bodies, each 12 to 15 miles in diameter, generate light in the X-ray wavelength range. Researchers at the University of Illinois Urbana-Champaign developed a new way spacecraft can use signals from multiple pulsars to navigate in deep space.
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Source: Phys.org