China has successfully launched experimental X-ray pulsar navigation satellite XPNAV-1. It is the world’s first pulsar navigation satellite or spacecraft. It was launched on board of Long March 11 solid-fuelled rocket from the Jiuquan Satellite Launch Center in China’s northwest. It was 239th flight mission of the Long March carrier rocket series. Key Features of XPNAV-1 satellite The satellite weighs more than 200 kilogrammesand carries two detectors. It will operate in a Sun-synchronous orbit (500 kilometers) inclined 97 degrees. It will conduct in-orbit experiments of autonomous spacecraft navigation using pulsar detectors to demonstrate new technologies. It will also test its detectors’ functions in responding to the background noise of the universe, outline pulsar contours, and create a database for pulsar navigation. What are pulsars? Pulsars are highly magnetized, rotating neutron stars that emit a beam of electromagnetic radiation. They are spherical, compact objects that are about the size of a large city but contain more mass than the sun. Scientists are using pulsars to study extreme states of matter, search for planets beyond Earth’s solar system and measure cosmic distance. What is X-ray pulsar navigation? X-ray pulsar navigation is an innovative navigation technology in which periodic X-ray signals emitted from pulsars are used to determine location of a spacecraft in deep space. This method of navigation, based on X-ray signals emitted from pulsars is known as XNAV. Potential Benefits XNAV is expected to provide a faster estimation of spacecraft location in space as current systems are limited by the time delay at great distances. It is also seen as a cheaper alternative for a radio-based system as it would require reduced ground infrastructure. Besides, it is expected to lead to autonomous spacecraft navigation in the future. It will also save additional cost as X-ray satellites can be made smaller and lighter.