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NASA's Got a Plan For a 'Galactic Positioning System' To Save Astronauts Lost in Space (space.com)
From a report: Outer space glows with a bright fog of X-ray light, coming from everywhere at once. But peer carefully into that fog, and faint, regular blips become visible. These are millisecond pulsars, city-sized neutron stars rotating incredibly quickly, and firing X-rays into the universe with more regularity than even the most precise atomic clocks. And NASA wants to use them to navigate probes and crewed ships through deep space. A telescope mounted on the International Space Station (ISS), the Neutron Star Interior Composition Explorer (NICER), has been used to develop a brand new technology with near-term, practical applications: a galactic positioning system, NASA scientist Zaven Arzoumanian told physicists Sunday (April 15) at the April meeting of the American Physical Society.
With this technology, "You could thread a needle to get into orbit around the moon of a disant planet instead of doing a flyby," Arzoumian told Live Science. A galactic positioning system could also provide "a fallback, so that if a crewed mission loses contact with the Earth, they'd still have navigation systems on board that are autonomous." Right now, the kind of maneuvers that navigators would need to put a probe in orbit around distant moons are borderline impossible.
With this technology, "You could thread a needle to get into orbit around the moon of a disant planet instead of doing a flyby," Arzoumian told Live Science. A galactic positioning system could also provide "a fallback, so that if a crewed mission loses contact with the Earth, they'd still have navigation systems on board that are autonomous." Right now, the kind of maneuvers that navigators would need to put a probe in orbit around distant moons are borderline impossible.
There is nobody that is even alive today, nor probably for the next several centuries, that is going to need something like this.
File under 'M' for 'Manic ranting'
the plaques on the Pioneer spacecraft launched in 1972 and 1973 showed the Earth's position from 14 pulsars
put people into space.
GPS works by triangulating between 4-6 satellites that are all spread out. A 3d hexagon with a person in the middle somewhere.
With extra-terrestrial navigation, the person is very far outside of that hexagon. It's really hard to find an exact position when you have multiple sources that - for all intents and purposes - are co-located. Get far enough from Earth and all GPS satellites are one dot in the distance. Looks like they've found a way to use various stars as the points of that hexagon. Cool.
But if you're lost in space, you should be more worried about air, water, food, temperature, and shelter.
Just having a screen telling me I'm two million light years from Andromeda, while interesting, is as useless as an eBook about a topic no one cares about.
...than to get off at the wrong exit of Intergalactic Highway 39.
Sorry, couldn't resist and get off my lawn.
Are people insane? Have you forgotten about the speed of light and basic physics? You aren't going to be visiting "distant moons" with crewed missions. That includes Mars.
Not really that new. The SR-71 had an "Astro-inertial navigation system" that could track stars day and night to locate the aircraft.
https://en.wikipedia.org/wiki/Lockheed_SR-71_Blackbird#Astro-inertial_navigation_system
In addition, the use of pulsars to accurately determine Earthly position had been considered since at least the 1980s [citation required]. (I worked for a major US inertial navigation test system outfit in the 80s and the use of pulsars was discussed to solve a particularly nasty set of specs required by one customer.)
America may have terminally lost its way but what about the Chinese ?
... when watching Star Trek, if currently NASA had in a mind a method that could be used much like a GPS.
This could very well be useful in our lifetimes if they were to build a ship powered by Ion, plasma, etc. drives that could point and go instead of relying on being thrown across space like a rock.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
GPS has what, ~3/4 meters precision? That's on Earth.
This would eventually have 1 km precision in _all_ of space. Ya that's a big circle on my futuristic, hologram smartphone Goopple Maps (c), but in _all_ of space?! Damn...
See Neutron pulse rate
So after our own solar system is utterly destroyed, the few survivors will still have some idea where they are! Unfortunately, faster than light travel still isn't even a remote possibility.
I've abandoned my search for truth; now I'm just looking for some useful delusions.
We have probes at the farthest edges of the solar system.
Indeed we do but crucially those probes do not contain astronauts nor can they do much more than float through the void so even if they got lost there is nothing they can do about it. With our current technology manned spacecraft have large teams of people on Earth monitoring them and very limited propulsion so getting lost is extremely hard and, if it happens, there is probably nothing to be done anyway. Indeed, given that the furthest anyone has ever gone so far is the moon you can find out where Earth is by just using your eyes.
This idea was used in Enterprise to signal the Borg. The episode was Regeneration, in the second season, involving the crashed Borg sphere from First Contact. The frequencies of three pulsars were used as position references to provide the location of Earth. The signal was sent by Borg drones in the 22nd century and would arrive in the delta quadrant in the 24th century. The approach for positioning sounds a lot like what's being done here.
We watched star trek and saw them do it.
So... they made a different version of GPS and named it... GPS? Global... Galactic... they might want a name that starts with a different letter.
Great! Atomic Clocks are already Stratum 0 in NTP. Does this make these new things Stratum -1?
Right now, the kind of maneuvers that navigators would need to put a probe in orbit around distant moons are borderline impossible.
Human space history is full of deemed impossible things that were accomplished.
The real challenge nowadays is to accomplish anything within modern space industry Quality Assurance standards.
The GPS said this wormhole was a shortcut!
Didn't the Ancients already figure this out using a set of six astrological symbols representing any point in space, with the seventh symbol representing the point of origin? Plus, Captain Samantha Carter figured out how to account for stellar drift.
If a probe is heading for a distant planet, it's moving pretty fast, because we don't want to wait several lifetimes to get the information back. If it's moving pretty fast, its nowhere near orbital speed for a moon (Triton?), and its trajectory is going to be limited so it won't be able to play fancy games with gravity slingshots. That's the big problem with getting into orbit. Not precision of trajectory.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes