NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Latitude AND Longitude by Noon Sun+GPS
From: Frank Reed CT
Date: 2004 Jan 25, 15:56 EST
From: Frank Reed CT
Date: 2004 Jan 25, 15:56 EST
Kieran K wrote:
"Frank makes two assumptions here:
1) That the modern GPS is a reliable tool. I suggest it is not
2) That most GPS units purchased are by ocean navigators. Here again I beg to differ."
Now, now... Be fair: those are your guesses about my assumptions. I wouldn't count either one of them as "my assumptions".
And wrote:
"The GPS unit at sea I understand is a very reliable and lifesaving instrument. The reason: The horizon on a boat is always visible."
A minor quibble: it's not the horizon 'per se', but a large fraction of the sky (down to 20 degrees altitude is nice). That's what you need so that you can see four satellites.
And wrote:
"The majority of GPS units sold in Australia I have been informed go to the recreational hiker and backpacker market. This is possibly due to the large number of tourists here and the smaller number of boaters. However I must confess that I don't know the exact reason. Whether this is the same overseas I don't know."
I'm sure that's true most everywhere. At any moment of time, there are far more people on land than at sea. There are far more people wandering around in the wilds of the US National Parks and Forests, for example, than there are sailing. I'm not sure what point you're making of this though.
And wrote:
"So Franks assertion that celestial navigation is no longer necessary unless there is an emergency is about half right. If there is an emergency you may not have to rely on CN as a last resort but you had better have something other than a GPS unit."
On land, under dense cover, yes. Also notice that you would have the same problems in the canyons of New York City that you find in the gorges of your Australian wilderness. There's hardly any easier place to navigate without tools of maps than Manhattan, but car navigation systems that use GPS just don't work in among the skyscrapers.
And wrote:
"if I had relied on GPS units for my expeditions the ants and dingoes would long ago have supped on my bones in the great Outback."
Youch. Yes, that's a good point! GPS is also useless underwater. I posted about "fish tags" that use a simple form of celestial navigation back in December. I think it's a fascinating example of the survival of celestial in the GPS Age, but no one "took the bait" back then. Also underwater, US submarines *do* use GPS on those occasions when they're trailing an antenna, but for the most part their navigation is inertial.
Frank E. Reed
[X] Mystic, Connecticut
[ ] Chicago, Illinois
"Frank makes two assumptions here:
1) That the modern GPS is a reliable tool. I suggest it is not
2) That most GPS units purchased are by ocean navigators. Here again I beg to differ."
Now, now... Be fair: those are your guesses about my assumptions. I wouldn't count either one of them as "my assumptions".
And wrote:
"The GPS unit at sea I understand is a very reliable and lifesaving instrument. The reason: The horizon on a boat is always visible."
A minor quibble: it's not the horizon 'per se', but a large fraction of the sky (down to 20 degrees altitude is nice). That's what you need so that you can see four satellites.
And wrote:
"The majority of GPS units sold in Australia I have been informed go to the recreational hiker and backpacker market. This is possibly due to the large number of tourists here and the smaller number of boaters. However I must confess that I don't know the exact reason. Whether this is the same overseas I don't know."
I'm sure that's true most everywhere. At any moment of time, there are far more people on land than at sea. There are far more people wandering around in the wilds of the US National Parks and Forests, for example, than there are sailing. I'm not sure what point you're making of this though.
And wrote:
"So Franks assertion that celestial navigation is no longer necessary unless there is an emergency is about half right. If there is an emergency you may not have to rely on CN as a last resort but you had better have something other than a GPS unit."
On land, under dense cover, yes. Also notice that you would have the same problems in the canyons of New York City that you find in the gorges of your Australian wilderness. There's hardly any easier place to navigate without tools of maps than Manhattan, but car navigation systems that use GPS just don't work in among the skyscrapers.
And wrote:
"if I had relied on GPS units for my expeditions the ants and dingoes would long ago have supped on my bones in the great Outback."
Youch. Yes, that's a good point! GPS is also useless underwater. I posted about "fish tags" that use a simple form of celestial navigation back in December. I think it's a fascinating example of the survival of celestial in the GPS Age, but no one "took the bait" back then. Also underwater, US submarines *do* use GPS on those occasions when they're trailing an antenna, but for the most part their navigation is inertial.
Frank E. Reed
[X] Mystic, Connecticut
[ ] Chicago, Illinois
