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Author Topic: Would my GPS device work on the moon?  (Read 33040 times)

Offline Bored chemist

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Would my GPS device work on the moon?
« Reply #25 on: 01/04/2011 18:21:51 »
To say "I was talking about the systems themselves being used with distances and time delays, that are set for earth, it's a given the satalites are designed to work in space."
implies that you already know that answer, I contend that you don't.
Of course, the system was designed to work on earth. So, in a sense, were people. But they still worked on the moon.
There are plenty of instances of things designed for one thing but used for others. The internet wasn't designed for distributing naughty pictures, but that's one of its major uses.

As for "A dozen or more:- facing the earth.", do you not realise that, for one thing , these were designed to spread a signal pretty much from horizon to horizon, and for another, antennae never form "perfect" beams- there's always some transmission in other directions?


"You mean based on a sphere shape,..."
No, I meant what I said.
A coordinate system based on earth (the one I had in mind was latitude, longitude and altitude) which can be used to pinpoint any place in the universe. Please don't presume to tell me what I mean.

"No, there are a few ways a GPS system can work, yet we are talking about the one we use."
There may be several ways you could set up a GPS system.
The one we use depends explicitly on exactly the time delays that you seem to think are a problem.

"And sending a signal from the moon to a satalite arround the earth would take too long, "
Too long for what? The delay would be less than two seconds. How much of a hurry are you in?

"besides the fact that they are designed to communicate with systems on the earth."
Still not important. It's not an issue of what they were designed to do, the question is about what they could do.

In principle, with the right decoding (normally restricted to military systems), a big enough aerial and the right software, you could find out your position on the moon by reference to the GPS system. The problems would be that it would give a result in earth based coordinates. But that's still telling you where you are. The other problem is that the accuracy would suck. That's not the same as saying it wouldn't work.

 

Offline imatfaal

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Would my GPS device work on the moon?
« Reply #26 on: 01/04/2011 19:03:00 »
And would the accuracy even suck? It would be worse than on the surface of the earth but you would have a dozen or more points, with separations between them of up to 50,000km (they are in 20,000 km orbits) from a distance of around 400,000 km.  The maths is beyond me, even if I did know what the inherent error margin were, but it doesn't strike me as too bad a deal - especially if there was no alternative.
 

Offline Geezer

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Would my GPS device work on the moon?
« Reply #27 on: 01/04/2011 19:27:34 »
And would the accuracy even suck? It would be worse than on the surface of the earth but you would have a dozen or more points, with separations between them of up to 50,000km (they are in 20,000 km orbits) from a distance of around 400,000 km.  The maths is beyond me, even if I did know what the inherent error margin were, but it doesn't strike me as too bad a deal - especially if there was no alternative.

The accuracy is a function of the angles formed at the GPS receiver between three or more satellites. The greater the angles, the more accurate the measurement. As you might imagine, the angles become rather acute when the receiver is on the Moon, so the accuracy won't be good.

I would think the accuracy is a function of the cosine of the angles formed between satellites and the receiver, so a small error in the lengths of the adjacent sides of the triangle produces a relatively large error in the resolved angle when that angle is small.
 

Offline Jolly- Joliver

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Would my GPS device work on the moon?
« Reply #28 on: 01/04/2011 20:27:02 »
To say "I was talking about the systems themselves being used with distances and time delays, that are set for earth, it's a given the satalites are designed to work in space."
implies that you already know that answer, I contend that you don't.
Of course, the system was designed to work on earth. So, in a sense, were people. But they still worked on the moon.
There are plenty of instances of things designed for one thing but used for others. The internet wasn't designed for distributing naughty pictures, but that's one of its major uses.

As for "A dozen or more:- facing the earth.", do you not realise that, for one thing , these were designed to spread a signal pretty much from horizon to horizon, and for another, antennae never form "perfect" beams- there's always some transmission in other directions?

That's very nice, but those directions are not 180 degree. Leaving only satalite on the other side of the earth(realtive to the moons position at the time) being able to send a signal in the moons direction at all, very hit and miss, if returned I think you'll find the satalite that sent it could have moved into a non reciving postion. plus the angles could send any signal retuen in a tottally different direction. Hoirson to horison or not it's not so clear sent signal would reurn to the satalite that sent them, your asking a satialite to perform a function it has not been tuned to doing. 



"You mean based on a sphere shape,..."
No, I meant what I said.
A coordinate system based on earth (the one I had in mind was latitude, longitude and altitude) which can be used to pinpoint any place in the universe. Please don't presume to tell me what I mean.

"No, there are a few ways a GPS system can work, yet we are talking about the one we use."
There may be several ways you could set up a GPS system.
The one we use depends explicitly on exactly the time delays that you seem to think are a problem.

"And sending a signal from the moon to a satalite arround the earth would take too long, "
Too long for what? The delay would be less than two seconds. How much of a hurry are you in?

Not going to matter if only one or two can pick it up, besides the distance would be greater, as the closest satalites to the moon wouldn't be able to transmit.

 


"besides the fact that they are designed to communicate with systems on the earth."
Still not important. It's not an issue of what they were designed to do, the question is about what they could do.

They could do lots of things, if we are talking about "coulds" then fine. Yes one day they could gives us gps on the moon.



In principle, with the right decoding (normally restricted to military systems), a big enough aerial and the right software, you could find out your position on the moon by reference to the GPS system. The problems would be that it would give a result in earth based coordinates. But that's still telling you where you are. The other problem is that the accuracy would suck. That's not the same as saying it wouldn't work.


If it's in accurate it isnt working.
 

Offline Geezer

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Would my GPS device work on the moon?
« Reply #29 on: 01/04/2011 21:26:22 »

I think you'll find the satalite that sent it could have moved into a non reciving postion


It doesn't matter if the signal disappears. The GPS receiver only needs to receive the satellite's signal once to determine a position.

You might want to take a look at this  http://en.wikipedia.org/wiki/Global_Positioning_System#Basic_concept_of_GPS
 

Offline Jolly- Joliver

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Would my GPS device work on the moon?
« Reply #30 on: 01/04/2011 22:21:30 »

I think you'll find the satalite that sent it could have moved into a non reciving postion


It doesn't matter if the signal disappears. The GPS receiver only needs to receive the satellite's signal once to determine a position.

You might want to take a look at this  http://en.wikipedia.org/wiki/Global_Positioning_System#Basic_concept_of_GPS

I referenced that link: "Although four satellites are required for normal operation, fewer apply in special cases. If one variable is already known, a receiver can determine its position using only three satellites."

You are saying a device having recieved just one signal from one satalite while on the moon, will be able to tell you where you are. Not the case.

It might be able to say: "You're on the moon"
« Last Edit: 01/04/2011 22:25:07 by Wiybit »
 

Offline Geezer

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Would my GPS device work on the moon?
« Reply #31 on: 01/04/2011 22:37:42 »
You are saying a device having recieved just one signal from one satalite while on the moon, will be able to tell you where you are.

No. I am not saying that at all. I am saying the receiver only needs to receive one transmission per satellite. Your point about the satellite moving is irrelevant.
 

Offline Jolly- Joliver

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Would my GPS device work on the moon?
« Reply #32 on: 01/04/2011 23:11:14 »
You are saying a device having recieved just one signal from one satalite while on the moon, will be able to tell you where you are.

No. I am not saying that at all. I am saying the receiver only needs to receive one transmission per satellite. Your point about the satellite moving is irrelevant.

They are designed to transmit to the earth, the moon is in the other direction to normal opperation. Personally I think only around 10% of the satalites up there at any one time could really transmitt in a luna direction anyway, that' 2.3 satalites but maybe it 20% that would 4.6 satalites.

Best case I see is 4.6 being in a position to do so but there is no garentee that would actually work, besides as I said before the program on the GPS device would have to have a map and record of the moon, to then place you with in that map.   
 

Offline Geezer

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Would my GPS device work on the moon?
« Reply #33 on: 02/04/2011 04:37:03 »
Now look here Wybit, either admit you were wrong and you have learned something, or provide some substantial evidence to support your arguments. It looks like all you are doing is trying to change the subject whenever you are challenged.

Sorry, but that's nothing but trolling. You can learn a lot on TNS (I have), but if you are confident you are always right, you are simply being a troll.

It's your call. Are you trying to prove something, or are you trying to learn anything?   
 

Offline syhprum

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Would my GPS device work on the moon?
« Reply #34 on: 02/04/2011 09:20:16 »
NASA have already acknowledged that to use the Earths GPS system for navigation on the Moon is all but impossible and to set up a similar system to cover the moon would be extremely expensive.
To this end they have let contracts to private companies to develop simple short range systems that will assist navigation on the moon.

http://www.thaindian.com/newsportal/world-news/nasa-developing-navigation-system-for-moon-lead_10074436.html
« Last Edit: 02/04/2011 09:22:24 by syhprum »
 

Offline Bored chemist

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Would my GPS device work on the moon?
« Reply #35 on: 02/04/2011 14:46:56 »
"Personally I think only around 10% of the satalites up there at any one time could really transmitt in a luna direction anyway"
Odd that, because, in reality, about half of them would (though the signal strength would be poor).
When you say "it's not so clear sent signal would reurn to the satalite that sent them," are you labouring under the delusion that GPS sends a signal back to the satellites? The GPS receivers are just receivers, not transmitters.
In other words, do you know what you are talking about? If not, perhaps you might think about learning rather than trolling.


Incidentally, if you use Google chrome as a web browser it highlights spelling errors for you. That way you don't end up pontificating about satellites without even knowing how to spell the word.
 

Offline Jolly- Joliver

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Would my GPS device work on the moon?
« Reply #36 on: 02/04/2011 17:57:05 »
Now look here Wybit, either admit you were wrong and you have learned something, or provide some substantial evidence to support your arguments. It looks like all you are doing is trying to change the subject whenever you are challenged.

Not the case at all. It is you and others that claimed that it would work. I disagreed from the beginning.


Sorry, but that's nothing but trolling.

You know what they say about insulting people.

But to clarify, The question was "Would my GPS work on the moon"

I said no, and that the satlites signal would not get there, that also the device needed a map of the moon to work at all.

Bored Chemist said no you didn't need a map and that GPS could tell you where you were any where in the universe.

He and others said that the signals from satellites, could get there, I replied to that no if that was possible I think "Think" only 10% of the satellites could do that- think, not a statement of fact, what I believed, based on the idea that the signals could get there, and the people making those assertions never backed up there claims with any evidence either I might like to point out.

In fact other than you Geezer I am the only one that actually referenced another site, and the site you reference was the one I did.

But as always there is a mis-communication, and misunderstanding.
 

You can learn a lot on TNS (I have), but if you are confident you are always right, you are simply being a troll.

It's your call. Are you trying to prove something, or are you trying to learn anything?   

I'm trying to answer the question, you all seem to think it would work, I disagree.

As I said before to work it would need a map of the moon

http://www8.garmin.com/aboutGPS/
Quote
Essentially, the GPS receiver compares the time a signal was transmitted by a satellite with the time it was received. The time difference tells the GPS receiver how far away the satellite is. Now, with distance measurements from a few more satellites, the receiver can determine the user's position and display it on the unit's electronic map.

This alone is enough to show that a GPS on the moon would not function, let alone be able to plot your position anywhere in the universe.


Another issue with the signals is solar winds which disrupt them, Still looking for the reference for that, but I did read it some where.

Other than that, the Next generation of GPS- WAAS is looking to increase the signal foot print of the GPS system http://en.wikipedia.org/wiki/Wide_Area_Augmentation_System

But even if the current signal was Horizon to horizon as Bored chemist claimed, it would not be beyond that would it, it would concentrate it's signal foot print or zone of sight, to perform it's function in the optimal manner, and that function is on the earth and for the earth, Why waste signal out into space?

 GPS started in 1978 I am not sure what the actual signal foot print is, but the technology from when it started is clearly dated today
http://www.apsattv.com/techinfo/predicting-out-of-footprint-coverage.htm

Site on satellite coverages- footprints and receptions outside of the signal foot print.

also on the signal front
http://www8.garmin.com/aboutGPS/
Quote
◦Number of satellites visible - The more satellites a GPS receiver can "see," the better the accuracy. Buildings, terrain, electronic interference(which I believe includes solar wind interference), or sometimes even dense foliage can block signal reception, causing position errors or possibly no position reading at all. GPS units typically will not work indoors, underwater or underground.

Should add or in space I think really.


"Personally I think only around 10% of the satalites up there at any one time could really transmitt in a luna direction anyway"
Odd that, because, in reality, about half of them would (though the signal strength would be poor).

Based upon what do you make that acertion? AS things stand I don't think any would.



When you say "it's not so clear sent signal would reurn to the satalite that sent them," are you labouring under the delusion that GPS sends a signal back to the satellites? The GPS receivers are just receivers, not transmitters.

I think you'll find the latest ones do blackberry and such like.
http://us.blackberry.com/smartphones/features/gps.jsp

But that is an assumption, Hence think.



In other words, do you know what you are talking about? If not, perhaps you might think about learning rather than trolling.


Incidentally, if you use Google chrome as a web browser it highlights spelling errors for you. That way you don't end up pontificating about satellites without even knowing how to spell the word.

Bored Chemist I have seen you make spelling mistakes also, Seriously poor show.
« Last Edit: 02/04/2011 18:04:55 by Wiybit »
 

Offline Jolly- Joliver

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Would my GPS device work on the moon?
« Reply #37 on: 02/04/2011 18:01:00 »
NASA have already acknowledged that to use the Earths GPS system for navigation on the Moon is all but impossible and to set up a similar system to cover the moon would be extremely expensive.
To this end they have let contracts to private companies to develop simple short range systems that will assist navigation on the moon.

http://www.thaindian.com/newsportal/world-news/nasa-developing-navigation-system-for-moon-lead_10074436.html

Interesting looks like they are going to develop one.
 

Offline CliffordK

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Would my GPS device work on the moon?
« Reply #38 on: 02/04/2011 18:37:18 »
So - If you were on the dark side of the moon (when you are part of the great gig in the sky) I think you would be unlucky - but on the side that faces the earth I reckon a decent receiver could pick up enough signals to make a fairly reasonable approximation.

Why wouldn't it work on the dark side of the moon facing earth?
The "Dark Side of the Moon" has nothing to do with the sun or illumination.
Rather, the moon is tidally locked with the earth.  One side of the moon always faces the earth.  One side (the dark side) always faces away from the earth.  Thus, if you were on the side of the moon facing away from Earth...  the GPS satellites would be useless.

As far as whether you could use a GPS system.
Obviously any software pre-programmed to positions on earth would be confused.

Are the antennas omni-directional antennas?  

I don't see why you couldn't make basic triangulation routines to map a position in space above the satellites...  and then map that onto the lunar surface based on lunar topography and the lunar orbit.

A time delay is irrelevant, and would just be part of the calculations.  The geosynchronous orbit is about 36,000 km.  The moon is at about 385,000 km.  It is likely one could pick up satellites on all sides of the earth that are not eclipsed by the planet. In fact, using the satellites on the far side of Earth, one should be able to pinpoint a location 385,000 km below the surface of the planet.

You can use GPS equipment in conjunction with a base station at a fixed location.  Putting a fixed base station on the moon would likely greatly simplify the calculations, and significantly improve the accuracy of the system.

Ahh...
This base station would be essentially one approach for doing the local triangulation.  One might be able to use the base station for calculating the offset even while not in direct sight of the base station.
« Last Edit: 02/04/2011 18:40:18 by CliffordK »
 

Offline Jolly- Joliver

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Would my GPS device work on the moon?
« Reply #39 on: 02/04/2011 19:39:18 »
So - If you were on the dark side of the moon (when you are part of the great gig in the sky) I think you would be unlucky - but on the side that faces the earth I reckon a decent receiver could pick up enough signals to make a fairly reasonable approximation.

Why wouldn't it work on the dark side of the moon facing earth?
The "Dark Side of the Moon" has nothing to do with the sun or illumination.
Rather, the moon is tidally locked with the earth.  One side of the moon always faces the earth.  One side (the dark side) always faces away from the earth.  Thus, if you were on the side of the moon facing away from Earth...  the GPS satellites would be useless.

As far as whether you could use a GPS system.
Obviously any software pre-programmed to positions on earth would be confused.

Are the antennas omni-directional antennas?  

I don't see why you couldn't make basic triangulation routines to map a position in space above the satellites...  and then map that onto the lunar surface based on lunar topography and the lunar orbit.

I dont know why you would need the luna orbit, to work it out.


A time delay is irrelevant, and would just be part of the calculations.  The geosynchronous orbit is about 36,000 km.  The moon is at about 385,000 km.  It is likely one could pick up satellites on all sides of the earth that are not eclipsed by the planet.

No I dis agree, The satalites set a signal zone an area they cover, I'm still looking for the exact size but, as the signal travel through the atmosphere it is distorted, meaning that signals that travel through and back out will be even more distorted, Besides I do not believe that really any signals travel out side of a zone of the earth they are designed to cover, there might be a very low frequency at the zone edges.


 In fact, using the satellites on the far side of Earth, one should be able to pinpoint a location 385,000 km below the surface of the planet.

Below the surface? What do you mean? GPS do not work indoors.



You can use GPS equipment in conjunction with a base station at a fixed location.  Putting a fixed base station on the moon would likely greatly simplify the calculations, and significantly improve the accuracy of the system.

Ahh...
This base station would be essentially one approach for doing the local triangulation.  One might be able to use the base station for calculating the offset even while not in direct sight of the base station.

The base staion would have to talk to the device. Personally I think for the size of the moon just 8 satalites, 4 for each face should be enough, but they would have to orbit the moon tho.

If you wanted to use the earths GPS satalites I think you would have to turn them to transmit straight at it, even then there is no garentee, Just look at the earth GPS system if you're indoors with four satalites in a good postions it wont work. Using the ones we have at the moment in there current function is just not possible, plus you would need your GPS to have a moon map also.   
 

Offline Pumblechook

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Would my GPS device work on the moon?
« Reply #40 on: 02/04/2011 20:28:37 »
The signals will be directed towards Earth and the distance to the Moon is 20 times further and just on that basis the signals would be 26 dB weaker (400 times less power).  You would need a fair sized parabolic dish.. 3 metre or more.
 

Offline Jolly- Joliver

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Would my GPS device work on the moon?
« Reply #41 on: 02/04/2011 20:30:29 »
The signals will be directed towards Earth and the distance to the Moon is 20 times further and just on that basis the signals would be 26 dB weaker (400 times less power).  You would need a fair sized parabolic dish.. 3 metre or more.

And point it in the moons direction, I still do not think any of the current signals get to the moon at all.
 

Offline Pumblechook

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Would my GPS device work on the moon?
« Reply #42 on: 02/04/2011 20:59:24 »
I meant even if they fired similar power towards the Moon the signals would be 400 times weaker.  If you knew what power was going towards the Moon (by accident) you could work out what size of receiving dish was required. The dish may be so large that the beamwidth might be a tiny fraction of a degree and may have to track the satellites and possibly may have trouble picking up the required 3.  No air and therefore no wind would make it possible to construct huge dishes.

My pal bounces 144 MHz signals off the Moon.

This Swiss bloke can hear his own echos..  Probably 1296 MHz which is not too far from GPS frequencies. 

 
 

Offline Bored chemist

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Would my GPS device work on the moon?
« Reply #43 on: 02/04/2011 21:20:01 »
"Bored Chemist said no you didn't need a map and that GPS could tell you where you were any where in the universe. "
Oh no I didn't.

"As I said before to work it would need a map of the moon"
No, it doesn't.
The "satnav" systems used in cars need a map, but the whole point of GPS is that it doesn't.

"This alone is enough to show that a GPS on the moon would not function, let alone be able to plot your position anywhere in the universe."
No it doesn't (though nobody said it would anyway).

"Why waste signal out into space?"
Because it's impossible not to ( with a finite sized antenna).

"Based upon what do you make that acertion? "
based on the fact that roughly half of them would be visible from the moon's earthward side and the laws of physics.

"I think you'll find the latest ones do blackberry and such like.
http://us.blackberry.com/smartphones/features/gps.jsp

But that is an assumption, Hence think."

Red herring. It doesn't matter that Blackberies have a built in transmitter. There is no system on the satellites to receive a signal from them.

You really haven't understood how GPS works.
 

Offline CliffordK

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Would my GPS device work on the moon?
« Reply #44 on: 02/04/2011 21:56:06 »

 In fact, using the satellites on the far side of Earth, one should be able to pinpoint a location 385,000 km below the surface of the planet.

Below the surface? What do you mean? GPS do not work indoors.


You have satellites on the Moon side of Earth (black).
Satellites on the far side of Earth (green).
Satellites eclipsed by Earth (red), which obviously won't give you a good signal.

Those satellites on the Moon side of Earth (black) may or may not give a good omnidirectional signal.  But, the calculations for them would have to be recreated for the signal going in the opposite direction than intended.

Those satellites on the far side of the Earth (green) should be able to give you an X, Y, Z coordinate, similar to having the target being on Earth.  However, the elevation calculation would turn up to be essentially negative.  Obviously not being below ground, but it would look to the GPS as being 400,000 km below ground.

Some of the far side satellites might have atmospheric interference (light green).  But, this would not be all the satellites.

We've believed for a long time that Earth's radio signals do in fact escape from Earth's atmosphere, and could potentially be picked up at great distances, even other star systems, with the obvious time lag. 

Your GPS accuracy outside of the Earth/Moon system would be low, unless someone added GPS-like transmitters to other satellites such as some of the sun orbiting satellites.
 

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Offline Jolly- Joliver

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Would my GPS device work on the moon?
« Reply #45 on: 02/04/2011 22:08:41 »
Shrunk
"Bored Chemist said no you didn't need a map and that GPS could tell you where you were any where in the universe. "
Oh no I didn't.

Oh yes you did!



"Based upon what do you make that acertion? "
based on the fact that roughly half of them would be visible from the moon's earthward side and the laws of physics.

Rather than just making a stament couldnt you actually provide some evidence?



"I think you'll find the latest ones do blackberry and such like.
http://us.blackberry.com/smartphones/features/gps.jsp

But that is an assumption, Hence think."

Red herring. It doesn't matter that Blackberies have a built in transmitter. There is no system on the satellites to receive a signal from them.

You really haven't understood how GPS works.

GPS Global position system, and there are a few, My hence think statement was based upon, the notion that a mobile phone which does communicate with the satlites, your conversation passes through then as you chat, can also generate a position not using the acutal GPS satalite systems no red herrings at all, or none intended. 
 

Offline Jolly- Joliver

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« Reply #46 on: 02/04/2011 22:14:45 »

 In fact, using the satellites on the far side of Earth, one should be able to pinpoint a location 385,000 km below the surface of the planet.

Below the surface? What do you mean? GPS do not work indoors.

Ok looking at the position of the satalites and the direction they will project their signals, they do not project into the area of the moon, it was based upon that that I said possibly only 10% could at all, draw the area and directions they would cover. It's clear to see they wouldnt, I still think none would but, if it was in anyway possible I "think" only two satalites on that picture could and that's the two closest to the red and there signals would also travel through the atmosphere.   

http://www.apsattv.com/techinfo/predicting-out-of-footprint-coverage.htm
GPS satalites are about 30 years old, this site list the coverage foot prints for some satalites.
« Last Edit: 02/04/2011 22:21:14 by Wiybit »
 

Offline Jolly- Joliver

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Would my GPS device work on the moon?
« Reply #47 on: 02/04/2011 22:28:34 »
The actual satalites are Block 2 f

http://en.wikipedia.org/wiki/GPS_Block_IIF

Still looking for their specs

In the 1990s they sent up block 2A

And im looking for their specs too

"The reception foot print"
 

Offline Jolly- Joliver

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Would my GPS device work on the moon?
« Reply #48 on: 02/04/2011 22:33:16 »
http://www.outdoorbits.com/satellite-systems-a-5.html

Dont know about the whole horizon to horizon the A2 doesn't even cover Europe completely

Quote
One of the more important aspects of satellite reception is the footprint of the satellite broadcasts you wish to receive. The footprint is the theoretical area covered by each satellite broadcast on the earth. Reception within this footprint will depend on dish size / LNB specs / receiver used also.
 

Offline Bored chemist

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Would my GPS device work on the moon?
« Reply #49 on: 02/04/2011 22:42:02 »
""Bored Chemist said no you didn't need a map and that GPS could tell you where you were any where in the universe. "
Oh no I didn't.

Oh yes you did!"

OK, for a start either show a quote where I said that or leave.



"Rather than just making a stament couldnt you actually provide some evidence?"
Let me get this straight.
Do you need evidence that about half the satellites would be visible, or you need evidence that you cannot produce a perfectly defined beam with a finite aperture?
Both are clear enough to me.

"GPS Global position system, and there are a few, My hence think statement was based upon, the notion that a mobile phone which does communicate with the satlites, your conversation passes through then as you chat, can also generate a position not using the acutal GPS satalite systems no red herrings at all, or none intended"

I'm sorry, but I simply don't understand that. Could you try reading through it then sorting it out please?
 I will just point out that I don't normally experience satellite delays on my mobile phone.

 

The Naked Scientists Forum

Would my GPS device work on the moon?
« Reply #49 on: 02/04/2011 22:42:02 »

 

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