A Galactic Positioning System is being developed at the International Space Station that could change the way that spaceships and probes navigate in space. This type of technology would eliminate the need to do imprecise fly-bys that probes currently have to do by planets to get close to them.
This could revolutionize the way that astronauts travel in space.
Galactic Positioning System
The Neutron Star Interior Composition Explorer (NICER), a telescope mounted on the International Space Station, is being used to develop a galactic positioning system. This announcement was made at the meeting of the American Physical Society by NASA scientist Zaven Arzoumanian on April 15.
Arzoumanian says that with this technology space programs will be able to send their probes directly into the orbit of specific moons instead of planning flybys. He adds that this could allow scientists to be able to navigate space if they lose communication from Earth. The navigation systems on the ships or orbiters would be autonomous and not controlled from Earth.
Currently, the technology that is available to astronauts doesn't allow them to navigate their way directly into the orbit of a planet or moon. LiveScience cites missions by Voyager 1 and Juno as examples of planned flybys. These missions were able to get close to the planets but not spend a large amount of time gathering more information.
Navigation in space works by using radio signals that are sent from the Earth. These signals are sent using giant antennas and probes and ships respond by sending back signal. That makes it easy to determine the overall distance of a signal traveling to the ship and back. Angles are difficult to determine using the same technique since antennas are only receiving the signal.
How Would This Work?
This galactic positioning system would use pulsars to give ships and probes directions. Pulsars are radio signals that seem to emerge from neutron stars with strong magnetic fields. The poles of the magnetic field rotate with the star and channel electromagnetic radiation in a certain direction. These pulses repeat at regular intervals.
George S. Downs was the first to suggest using pulsars for space navigation in 1974. Downs says that positions could be measured within 95 miles (150 kilometers) using a radio antenna and 24 hours of data on the signals.
NASA's Station Explorer for X-Ray Timing and Navigation (SEXTANT) program are the team working on the galactic positioning system. They were able to track the ISS within 4.3 miles in two days. This is the first time that humans have used pulsars to navigate. Researchers hope to hit the next milestone of tracking the station within 1.9 miles and eventually get to tracking it at a range of 0.6 miles.
There's still a lot to work out, this demonstration occurred in low-Earth orbit which makes it more difficult to be able to track pulsars. Out in space, it will be easier with signals coming in straight lines.