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Old 20-09-2018, 15:57   #31
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

Quote:
Originally Posted by hpeer View Post
14murs14 is making a great point that I think people are missing.

Let’s say you find $1,000 laying in an envelope on your nave table, the envelope says “Thanks, use this to stay alive.”

How would you use that money? What the best use for that money?

It most likely is not on a sextant, but more likely a better jack line system, feathers, mast steps, harness, new anti-skid, a rowabke dink, or a gazzilion other things.

Full disclosure:
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How about this: an automatic engine room fire protection system, new upgraddd fire extinguishers, new CO and fire detectors. And a fuse in your starter and alternator charge circuit.
I'd buy a better sextant. My Davis sextant needs constant realignment.

I believe this thread was not about a cost/benefit analysis and comparative economics, but specifically about GNSS reliability.

To 14murs14: The FAA thinks the risk is great enough to keep the critical old land-based VOR stations running, even though they'd really love to shut them all down. It's an expensive 1950s-based technology, but the FAA knows there's a risk of a widespread GPS failure. And that old technology would keep the air traffic system going if or when GPS goes keel up. With VORs still running as a backup, I don't worry about 747s landing in my living room. Nor should anyone else.

GPS is probably being jammed at this very moment in the Black Sea by the Russians. Jamming GPS is one of the first actions likely to take place during geopolitical tensions. And it's a very viable way to deny use to us of our own harbors. If you've been paying attention, things have gotten a little "tense" with China, Russia, and North Korea. Jamming GPS is cheap, deniable, and doesn't put their troops in harm's way. It has all the same advantages as cyber attacks. It's a no-brainer first-action tactic.

Mariners have no backup. But since there isn't a risk of boats landing on people's homes, I guess no one cares.


Here's my "full disclosure:"
USCG licensed Master, Near Coastal
FAA Commercial Pilot: airplanes (single and multi), helicopters, gliders, with instrument rating
FCC licensed GMDSS Maintainer
Senior Advisor and cyber risk analyst for a "four letter" Fed. agency
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Old 20-09-2018, 16:17   #32
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

Why worry about super ulikely nightmare scenarios. Most boats are one lightning strike or battery failure away from the good old days of sextant and oil lamps. You may have a handheld if you saw it coming and the cooker worked as a Faraday cage but don't bank on it and how many batteries will you have. Turn it all off a d go for a sail as a training exercise. Even the US Navy have reintroduce it to there training.
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Old 20-09-2018, 16:27   #33
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

Yup, tires first if you really need ‘em.

Exactly my point.
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Old 20-09-2018, 17:05   #34
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

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Originally Posted by roland stockham View Post
Why worry about super ulikely nightmare scenarios. Most boats are one lightning strike or battery failure away from the good old days of sextant and oil lamps. You may have a handheld if you saw it coming and the cooker worked as a Faraday cage but don't bank on it and how many batteries will you have. Turn it all off a d go for a sail as a training exercise. Even the US Navy have reintroduce it to there training.
Fortunately, we don't get much lightning here on the West Coast. You're right about the US Navy reintroducing celestial navigation training. There's a reason they did that.

The FAA's NextGen air traffic control system is being developed where I work - just down the hall. Let's just say that: it was very wise to keep a skeleton of the old land-based aeronautical navigation elements up and running.

We will get eLORAN someday. It's necessary to have a backup. If the GNSS systems get jammed, AIS goes down with it, and our busiest harbors need AIS. Without AIS, we'd have to cut the traffic to a trickle. What I object to is that we don't have it now, and the politicos in Washington want to make it pay-for-play. Decommissioning WWV/WWVH, which gives voice status reports on GPS and announcements of severe maritime weather, is also short sighted. And it bugs me that I'll have to get time announcements from Russia for calculating longitude (if my time is off by 1 minute, my position is off by 4 miles).

As for myself, I'm using both GPS and GLONASS for navigation and AIS. I'm waiting for Galileo to come on line, then I'll use that instead of GLONASS. Using two constellations may be better than one, but not as good as having a jam-resistant navigation reference like eLORAN. The Europeans are ahead of us there. There's a good reason why they're spending the money for it. They don't want their cargo traffic shut down.
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Old 20-09-2018, 17:30   #35
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

Quote:
Originally Posted by Cpt Pat View Post
I'd buy a better sextant. My Davis sextant needs constant realignment.

I believe this thread was not about a cost/benefit analysis and comparative economics, but specifically about GNSS reliability.

To 14murs14: The FAA thinks the risk is great enough to keep the critical old land-based VOR stations running, even though they'd really love to shut them all down. It's an expensive 1950s-based technology, but the FAA knows there's a risk of a widespread GPS failure. And that old technology would keep the air traffic system going if or when GPS goes keel up. With VORs still running as a backup, I don't worry about 747s landing in my living room. Nor should anyone else.

GPS is probably being jammed at this very moment in the Black Sea by the Russians. Jamming GPS is one of the first actions likely to take place during geopolitical tensions. And it's a very viable way to deny use to us of our own harbors. If you've been paying attention, things have gotten a little "tense" with China, Russia, and North Korea. Jamming GPS is cheap, deniable, and doesn't put their troops in harm's way. It has all the same advantages as cyber attacks. It's a no-brainer first-action tactic.

Mariners have no backup. But since there isn't a risk of boats landing on people's homes, I guess no one cares.


Here's my "full disclosure:"
USCG licensed Master, Near Coastal
FAA Commercial Pilot: airplanes (single and multi), helicopters, gliders, with instrument rating
FCC licensed GMDSS Maintainer
Senior Advisor and cyber risk analyst for a "four letter" Fed. agency
CISSP and CISA
So how do you navigate when flying offshore again? Maybe I was just a crappy pilot, but for the life of I couldn't receive VOR signals more than about 50 miles max offshore, much less when I was lower. And if you're in IMC flying a GPS approach the fact that a VOR exists is going to help you how again, does every GPS approach have a missed to a VOR and you've got that dialed in when you're flying it? I'll give you a little hint why the FAA is forced to still maintain all those VORs because we ran into the same buzzsaw in the Coast Guard when we tried to decommission Loran-C. It's all about a little organization called AOPA that given your tagline I'm sure you're continually letter bombed by just like I am. They manage to have a strong enough lobby that at one point we were spending enough every year maintaining the Loran-C network that we could have bought every one of the whining GA pilots with a Loran-C receiver 5 shiny new GPS receivers, just because they were whining about how much it would cost them to replace their Loran-C receivers!

I basically echo your brag sheet except recently retired from a four letter agency calle the USCG and plus an electrical engineering degree from the Coast Guard Academy which means it focused almost entirely on electronic nav systems and specifically GPS. If your risk folks are telling you that wide area GPS jamming is a thing such that ships at sea hundreds or thousands of miles away from a conflict are going to lose the ability to navigate than you might want to hire some electrical engineers with some signals background to supplement your risk folks!
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Old 20-09-2018, 17:32   #36
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

Quote:
Originally Posted by hpeer View Post
14murs14 is making a great point that I think people are missing.

........
The OP question was asking how could GPS be lost and are these ways plausible. Saying that it can't happen and peeing off the deck is dangerous isn't much of an answer. I don't see any posts that imply people are worrying themselves sick over the possibility. The chances of loosing all GPS is very remote, but so is getting into extreme weather.

Most cruisers take precautions to avoid mooring GPS by having multiple sources and using a Faraday cage to protect at least one of them. That covers the most likely failure scenario, lightning.
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Old 20-09-2018, 17:32   #37
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

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You're right about the US Navy reintroducing celestial navigation training. There's a reason they did that.
That's a statement coming from someone who clearly never attended one of the service academies!
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Old 20-09-2018, 18:14   #38
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

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Originally Posted by 14murs14 View Post
So how do you navigate when flying offshore again? Maybe I was just a crappy pilot, but for the life of I couldn't receive VOR signals more than about 50 miles max offshore, much less when I was lower. And if you're in IMC flying a GPS approach the fact that a VOR exists is going to help you how again, does every GPS approach have a missed to a VOR and you've got that dialed in when you're flying it? I'll give you a little hint why the FAA is forced to still maintain all those VORs because we ran into the same buzzsaw in the Coast Guard when we tried to decommission Loran-C. It's all about a little organization called AOPA that given your tagline I'm sure you're continually letter bombed by just like I am. They manage to have a strong enough lobby that at one point we were spending enough every year maintaining the Loran-C network that we could have bought every one of the whining GA pilots with a Loran-C receiver 5 shiny new GPS receivers, just because they were whining about how much it would cost them to replace their Loran-C receivers!

I basically echo your brag sheet except recently retired from a four letter agency calle the USCG and plus an electrical engineering degree from the Coast Guard Academy which means it focused almost entirely on electronic nav systems and specifically GPS. If your risk folks are telling you that wide area GPS jamming is a thing such that ships at sea hundreds or thousands of miles away from a conflict are going to lose the ability to navigate than you might want to hire some electrical engineers with some signals background to supplement your risk folks!
OK. It's a long post. Pardon me if I miss anything.

How did aircraft navigate offshore before GPS? At 30,000 feet, the VHF horizon is 400 miles. Beyond that, inertial navigation and sometimes ADF. And if you go way back, pilots used a sextant. They even had special observation windows for doing sightings. And yes, I still dial in the VOR and have the VOR and ILS approach plates ready in case the RAIM alarm goes off on the GPS (for those who aren't familiar, a RAIM alarm indicates the GPS position can't be trusted). Which has happened to me. Don't you? The pucker factor can get real high if you haven't prepared for a non-GPS approach in IFR. When I fly with a second pilot, I assign the VOR or ILS approach to that pilot, and say: "if the GPS fails, you fly the approach." That way, it's completely prepared for. Make use of all available resources. It's part of the CRM (crew resource management) training.

The FAA explicitly decided to maintain the VOR stations for a backup to GPS. Read the announcement I linked above.

I agree that lobbying by end-user special interest groups who don't want to upgrade is a factor, but in the case of GPS, there have been too many cases of people installing Chinese-made GPS jammers bought on eBay and Amazon to jam their employer's or parents' GPS vehicle monitoring - who then park the vehicles in the airport parking right under the approach path to a major airport - and then go off on a two week vacation. Then the RAIM alarms go off on the flight decks. "Missed approach! (We just wasted $5,000)." The airlines have also asked for VOR as a backup. It can be either that, or divert to another airport.

It takes just four purpose-built jamming satellites in medium earth orbit to wipe out GPS (and the other GNSS constellations), and "selective denial" of GNSS over smaller areas is an already planned-out tactic of more than one military. If your training is current, you must have encountered that. I'm not saying we'd do that, but not every military is as noble in its rules of engagement as is ours. Have you been watching North Korea's launches of "research" satellites?

Please read the quote from the Director of National Intelligence that I included in an earlier post. He's not making this stuff up. I'll defer to his expertise, and I'm sure AOPA didn't influence him. He said "enhanced" ability to jam GPS. That ability already exists.

It seems that we both hold EE degrees. And at least a BSEE seems to be required to just walk in the door here. We do have a bit of comms experience: our radio network extends to Neptune.

Finally, I appreciate your Coast Guard service. Thank you. I can't count how many lives I have seen saved by the Coast Guard over the 20 years I've been on the sea. Every one of you are heroes in my book.
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Old 20-09-2018, 18:54   #39
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

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Originally Posted by Cpt Pat View Post
OK. It's a long post. Pardon me if I miss anything.

How did aircraft navigate offshore before GPS? At 30,000 feet, the VHF horizon is 400 miles. Beyond that, inertial navigation and sometimes ADF. And if you go way back, pilots used a sextant. They even had special observation windows for doing sightings. And yes, I still dial in the VOR and have the VOR and ILS approach plates ready in case the RAIM alarm goes off on the GPS (for those who aren't familiar, a RAIM alarm indicates the GPS position can't be trusted). Which has happened to me. Don't you? The pucker factor can get real high if you haven't prepared for a non-GPS approach in IFR. When I fly with a second pilot, I assign the VOR or ILS approach to that pilot, and say: "if the GPS fails, you fly the approach." That way, it's completely prepared for. Make use of all available resources. It's part of the CRM (crew resource management) training.

The FAA explicitly decided to maintain the VOR stations for a backup to GPS. Read the announcement I linked above.

I agree that lobbying by end-user special interest groups who don't want to upgrade is a factor, but in the case of GPS, there have been too many cases of people installing GPS jammers bought on eBay and Amazon to jam their employer's or parents' GPS vehicle monitoring - who then park the vehicles right under the approach path to a major airport. And then the RAIM alarms go off on the flight decks. "Missed approach! (We just wasted $5,000)." The airlines have also asked for VOR as a backup. It can be either that, or divert to another airport.

It takes just four purpose-built jamming satellites in medium earth orbit to wipe out GPS (and the other GNSS constellations), and "selective denial" of GNSS over smaller areas is an already planned-out tactic of more than one military. If your training is current, you must have encountered that. Not every military is as noble in its rules of engagement as is ours.

Have you read the quote from the Director of National Intelligence that I included in an earlier post? He's not making this stuff up. I'll defer to his expertise, and I'm sure AOPA didn't influence him. He said "enhanced" ability to jam GPS. That ability already exists.

It seems that we both hold EE degrees. And at least a BSEE seems to be required to just walk in the door here. We do have a bit of comms experience: our radio network extends to Neptune.

Finally, I appreciate your Coast Guard service. Thank you. I can't count how many lives I have seen saved by the Coast Guard over the 20 years I've been on the sea. Every one of you are heroes in my book.
Did navigate by sextant and ADF, don't now and haven't for a long time. Because we use GPS now! Again, thousands of aircraft fly offshore every day depending on GPS, not sextants or ADF. I did so for years, as did all my fellow CG pilots who do to this day. I'm not saying it's not possible to fly offshore without GPS, I'm saying we depend on it now for thousands of flights a day and you can too as a mariner.

I don't see your quote from the Director of Naval Intelligence or any references to four purpose built satellites in medium earth orbit blanking out all satellite based navigation (gonna actually call BS on that given the power it would require alone). And or course if we're in a situation where a country sneaks satellites into orbit and kills all satellite based navigation on earth, the world is in a situation where your ability to use GPS on your sailboat is the least of all of our concerns!

Yes, we could have a worldwide loss of GPS, just like we could have global thermonuclear war, or a chemical or biological attack, or any number of bad things. Directors of Naval Intelligence are paid to worry about these kind of things. We call civilians who buy CBRN suits, build bunkers, and takeother action in response to these both unlikely to happen and "life as we know it ending" events we call them Preppers, and this has veered into a Prepper level discussion.
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Old 20-09-2018, 19:08   #40
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

The output power from the GPS satellites is, are you ready... 25.6 watts. A little more than your VHF radio on your boat.

The antenna gain is listed at 13 dBi. Thus, based on the frequency allocation filing, the effective radiated power would be about 500 Watts (27 dBW).

Now, the free space path loss from 21000 km is about 182 dB. Take the 500 Watts (27 dBW) and subtract the free space path loss (27 - 182) and you get -155 dBW.

-155 dBW at the surface. That's 0.0000000000000005 watt. Not exactly something that's hard to jam. To put that into perspective, that's much less than the kinetic power of a snowflake hitting the ground. eLORAN uses 100,000 (or more) watt transmitters that are a lot closer than 21000 km away - which is why that system is jam-resistant.

14murs14: please check my math. I did a bit of rounding.

The extent of my "prepper" activities have been making sure I have enough room in my on board microwave oven to hold my handheld devices in a thunderstorm. And having a sextant, which I consider normal boat equipment.

I'm not a worrier. The likelihood of GPS getting jammed worldwide is maybe only a little higher than WWIII. And the likelihood that the Titanic would sink on its first voyage was what? Well, almost zero, until it happened. I like to think that people aren't stupid. But sometimes I'm wrong. Do the people in charge in Washington make you feel warm and fuzzy? Only you can decide on that.

But the chances of it getting jammed over a much smaller area is 100%. It's Almost certainly happening right now, somewhere, mostly in the Black Sea. Thank Putin.

The OP question was: "Scenarios for losing GPS/GLONASS/Galileo constellations: are they plausible?" My answer is: "It's possible. Here are my facts. You decide on plausibility."
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Old 20-09-2018, 21:05   #41
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

Folks, with keeping the batteries charged, the fridge running so the food does not go bad, the toilets unplugged, the kitty litter out of the bilge pump suctions, the soap scum out of the sullage tank, enough beer and tucker in the fridge, the dishes and the clothes clean and the water tank full, the engine oil changed on time, the fouling off the prop, the anchor chain from dribbling rust on the deck, the anchor on the end of the chain and dug into the bottom etc, who among us who is out there cruising has the time or inclination to be paranoid about some silly bugger turning the GPS system of.

And, what sort of a moron would consider doing so where half the population cannot find their way to the corner store for a pint of milk without their GPS enabled smart phone - the political toll would be devastating. Murdering a few hundred thousand people in Syria might go unnoticed but turn the GPS system off mate and the whole world would rise against you.
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Old 20-09-2018, 21:33   #42
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Talking Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

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I launched my sail boat in 1987 and sailed up and down the coast of Western Australia until about 1999 without a GPS. It's really not so long ago that we stumbled about and managed to pretty well stay off the rocks without GPS and electronic chart plotters.

If you are really feeling paranoid about the loss of the GPS system you should probably buy a radar. If you are off the east coast of the US just travel west until you can see land on the radar then travel N or S until you recognize some place.
Roger That. In the 1970's and 80's, we had a Cal 29 sailing out of SF Bay, often in the fog, in ocean races up an down the coast and out to the Farallones. Part of this time we didn't even have Loran and never had radar. We relied on DR, depthsounder, the Coast Pilot for description of landmarks, the Light List, and the highly inaccurate radio beacons to approximate where we were, and on a radar reflector and trusting the big boys out there to be on watch.

This is not to brag about, since everybody did it that way. Just to remind that GPS is only like icing on the cake when it comes to navigation.

GPS and radar allow us to safely take our boats into much closer quarters than we could have dared to attempt before, and to reduce navigator's workload dramatically. So without GPS, the cautious mariner will often just take a little longer to get to his destination safely.

We'll be heading out of the Bay, south to Mexico in a month. I wouldn't delay our departure for one minute if every satellite in the sky had come crashing down. Oh that reminds me to fix our long broken and unused paddlewheel log.
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Old 20-09-2018, 21:49   #43
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

As 14murs14 noted, the big difference between a sailboat and an airplane is the length of time it takes to get in trouble without GPS.

A short term loss of GPS is only a minor inconvenience to a sailboat. If you are not sure of your location, the safest thing is to take down the sails and drift - or anchor if inshore - until the GPS returns.

If the GPS doesn't come back, we're probably at war. In that situation, you probably don't want to continue your pleasure cruise in a plastic boat. Call the CG or Navy and ask for instructions.
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Old 20-09-2018, 22:16   #44
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

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Jammer, I think it was Arthur C. Clarke who back around 1960 pointed out that all it takes is a handful of buckshot,
A handful?? I am skeptical of this. It could only be true if...

There is an issue with chain reaction that once satellites start breaking into pieces more and more of them will. It is something like a forest fire that once started must burn out, cannot be put out.

It is not known if we already have enough satellites that we are vulnerable to this, but it's not far off.

Once this happens, it could make the low earth zone unusable for satellites for hundreds or thousands of years. It cost a lot more to use higher orbits.
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Old 20-09-2018, 22:28   #45
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Re: Scenarios for losing GPS/GLONASS/Galileo constallations: are they plausible?

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As I posted in the celestial nav thread, if you really believe that there's any chance that the entire GPS constellation will be taken out you would never step foot on an airplane
unless the pilot is completely incompetent, you should still survive even if gps fails.

With that said, I would never get on an airplane for other reasons.

You don't have to lose the satellites. All you need is one enemy who hides a gps jam er on your boat that activates offshore. If it is clever it can give you an incorrect fix, purposefully putting you into harm such as rocks or reef in poor visibility, doing nothing the rest of the time waiting months or years for the perfect opportunity.

In either case, you can just use celestial navigation. It is very easy today using the celestial navigation plugin for opencpn. You simply enter your sextant readings.

You can do running fixes, and use any star or planet, even the moon. Azimuth (compass based) which was never used in historical times because of the very complex computations as well as not having an accurate magnetic model for the earth is now possible. So a single sight can give you a fix.

The plugin also supports lunar sights in case you lose track of time. Who knows, maybe soon, it can automatically take sights with a camera and work similarly to a gps. Theoretically in this mode the accuracy could be within few hundred meters using cheap digital cameras, and gyros, and great software if enough celestial bodies can be observed.
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