X-ray pulsar-based navigation
X-ray pulsar-based navigation and timing (XNAV) is a theoretical navigation technique whereby the periodic X-ray signals emitted from pulsars are used to determine the location of a spacecraft in deep space. A spacecraft using XNAV would compare received X-ray signals with a database of known pulsar frequencies and locations. Similar to GPS, this comparison would allow the spacecraft to triangulate its position accurately (±5km). The advantage of using X-ray signals over radio waves is that X-ray telescopes can be made smaller and lighter. 
SEXTANT (Station Explorer for X-ray Timing and Navigation Technology) is a NASA funded mission being developed at the Goddard Space Flight Center that will test XNAV on-orbit on-board the International Space Station. It is currently planned for October 2016. 
- Commissariat, Tushna (4 June 2014). "Pulsars map the way for space missions". Physics World.
- "An Interplanetary GPS Using Pulsar Signals". MIT Technology Review. 23 May 2013.
- "NASA Builds Unusual Testbed for Analyzing X-ray Navigation Technologies". NASA. 20 May 2013.
- "The Neutron star Interior Composition ExploreR Mission". NASA. Retrieved 13 November 2014.
- Autonomous Spacecraft Navigation With Pulsars, W.Becker, M.G. Bernhardt & A.Jessner, in Acta Futura 2013
- Johns Hopkins APL to Develop Deep Space Navigation Network
- US Government Contract Proposal for X-Ray Pulsar Based Navigation and Time Determination
|This space- or spaceflight-related article is a stub. You can help Wikipedia by expanding it.|