Published: 11 March, 2009, 19:07
Edited: 11 March, 2009, 19:07
Russia is developing a navigation system based on tracking X-ray pulsars – a kind of neutron star, which will be used for deep space missions.
Pulsars are very heavy objects that may remain in place of a supernova, which emit a pulsing beam of electromagnetic radiation.
The navigation system developed by the Russian Institute of Space Research will use these periodic signals to determine its position in space just like GPS navigators use signals from satellites. Unlike GPS, however, it works fine anywhere in the Solar System and thus future missions to the Moon or Mars will have a use for it.
“Our calculations indicate that an X-ray navigation system can provide a spacecraft with positioning precision of hundreds or even dozens of kilometres,” told the Interfax news agency Yury Zaitsev, an expert from the institute.
Pulsars are a kind of neutron stars with a strong magnetic field. For reasons not yet fully known by scientists, they shoot a focused beam of electromagnetic radiation along with its magnetic axis. As with all neutron stars, pulsars rotate at a very high rate. When the rotation axis does not coincide with the direction of the beam, the resulting effect is similar to a lighthouse in space. When the first pulsar was discovered in 1967, astronomers thought the pulsating signal was artificial and called the object LGM-1 standing for ‘little green men’. The regularity of pulsar signals varies from seconds to milliseconds, and some are said to be precise as an atomic clock.
He added that the resolution of the ‘pulsar navigator’ may be even higher if the scientists research the signals’ characteristics further, and make more sensitive X-ray detectors. According to Zaitsev, this work is being done by the INTEGRAL space observatory and crew of the International Space Station.
The Russian project in not the first one to use pulsar signals for space navigation. In 2006, Pentagon’s research division DARPA announced it wanted to use a similar approach to double-check the positioning of military satellites.
Usually satellites determine their position using signals from other satellites, but in case of war those could be disrupted or faked by the enemy. Pulsar signals are more reliable and allow for greater security of the satellite constellation.