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Naval Academy Reinstates Teaching of Celestial Navigation
HughPickens.com writes: At the US Naval Academy in Annapolis, midshipmen studied celestial navigation for more than a century -- until 1998, after a decision that came after months of discussion that began with a 1996 curriculum review. Midshipmen were relieved. Celestial calculations were painfully difficult, requiring a nautical almanac and volumes of tables. Now Tim Prudente reports at the Capital Gazette that the Navy has reinstated the teaching of celestial navigation in the manual issued two months ago. The first midshipmen to receive training were juniors during this past summer school. Future classes will learn theories of celestial navigation during an advanced navigation course. And the Class of 2017 will be the first to graduate with the reinstated instruction.
But is there really any point in knowing how to navigate by the stars in a world of GPS? "In the event that we had to go into a national emergency, we would probably have to shut the GPS down because it can be used by potential enemies," says retired Navy Capt. Terry Carraway. "We went away from celestial navigation because computers are great," says Lt. Cmdr. Ryan Rogers, the deputy chairman of the academy's department of seamanship and navigation. "The problem is, there's no backup."
But is there really any point in knowing how to navigate by the stars in a world of GPS? "In the event that we had to go into a national emergency, we would probably have to shut the GPS down because it can be used by potential enemies," says retired Navy Capt. Terry Carraway. "We went away from celestial navigation because computers are great," says Lt. Cmdr. Ryan Rogers, the deputy chairman of the academy's department of seamanship and navigation. "The problem is, there's no backup."
Why wouldn't the military just turn their encryption keys back on so that they can use it but others get worse data? I do agree that teaching your officers celestial navigation is important, but when shit hits the fan, it will be interesting to see which ones actually retain it and can use it without constant practice.
They're not doing this in case they have to turn off the GPS. They're doing this because they realize that the enemy may be able to turn off the GPS (along with everything else that relies on modern microelectronics).
On a pitching, rocking ship in the middle of the sea, with a sky that may have cloud coverage so you don't have much choice in the stars that you can shoot? A picture of the sky tells you very little - you need the angle of the celestial object relative to the local horizon. A good human navigator might be able to shoot a few stars through a hole in 9/10ths cloud coverage and get a fix.
Star-trackers work well in space because the platform is relatively stable and you don't have any clouds (usually). Apollo 13 had problems with its star tracker after the explosion because of a cloud of reflective debris around the ship. They had to do a manual burn sighting the Earth's terminator through the reticle.
Not saying a computer couldn't be designed to do it, but getting a robust cel-nav system for sea vessels that can handle the noisy environment that is the sea and sky will be a challenge. Humans still beat computers in some things, this is one of them.
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Analog instruments in a typical aircraft "six pack" are quite useful when in the air but mostly useless if floating on water. About the only useful instrument of those would be the magnetic compass. These instruments are also only useful in getting a rough position in the air, close enough to get within visual or radio range of an airport. When on the water one's visible distance is greatly diminished, and in a time of war one might not want to broadcast their position with a radio.
Also, who says that the USNA does not also teach how to use instruments similar to that on an aircraft? I expect that they do. I suspect that those are also just as fragile as GPS in a time of war. Celestial navigation is cheap, readily available, and impossible to "jam", so long as you know how to do it.
You might think it "utterly retarded" but people smarter than both of us disagree with you.
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On the 1991 cruise I was on when in the Navy, our ship's GPS went out. No way to fix it. We had to use compasses and star charts till we got to Pearl Harbor so it could be fixed. If the guys hadn't been trained for it, we'd have been screwed.
Exactly. Tech can fail or be disabled, either deliberately or due to enemy action. Remember how Russia was testing their GPS jamming tech against the US a few years ago in the middle east, by providing it to one of the countries we fought? Similarly, Iran used GPS to bring down a drone. Our guys need to be able to get by without it and, for that matter, to confirm that the computer is right.
It's not like we're requiring every enlisted man to know this stuff--but the officers on a ship of war should damn well know how to navigate by the stars if they have to.
Assuming it's cloudy, you're GPS systems just went down, all radio navigation aids are lost, and all your compasses were demagnetized, then, yes, I assume one could say they are fucked.
One solution to this problem is like what reboot246 says in a sister post, have a sun stone as part of the celestial navigation gear. Another is to sail into a best guess of a safe direction until one can see a point of reference, be it a celestial object or terrestrial one.
Celestial navigation is not supposed to solve all navigation problems. What it is supposed to do is reduce the reliance on GPS to the point that should it go down you don't have a navy full of ships that can't so much as steer towards a safe harbor.
Having talked with people that sailed at sea, both for pleasure and for the US Navy, every ship has a number of readily available means to navigate. GPS is typically the primary means. Second on the list is likely to be radio navigation of one type or another. Third is typically dead reckoning. If you know where you were, what direction you are heading, and at what speed, you can usually keep sailing with relative safety and ease until you can restore one or the other means of electronic navigation. Those knowledgeable of celestial navigation can go without the electronic navigation for much longer and still reach their destination as scheduled. If it's cloudy while you are without electronic navigation aids then, yes, you will most likely arrive behind schedule.
In war you may not have the luxury of reaching your destination late.
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