NavList:

The Twitter Cel Nav Challenge

The recent thread entitled "Is Sextant a generic word?" shows that most of us have been in social situations where we had to explain what we were doing (sextant in hand) to a total stranger with presumably no knowledge of celestial navigation, position finding or even that the sky could tell us something about where we are. This is particularly a problem with the younger generation because they no longer look up but spend most of their time looking down towards their smartphones.

So the "Twitter Cel Nav Challenge" is this -- what would you say in 140 words or less to explain what you are doing?  Assume that if you fail to convince the person, the police will arrive shortly. [0]



 


"The almanac tells us where a star is. The sextant tells us how far from under it we are. A little calculation gives our position."  Ken Gebhart [1]

"I'm taking a class in celestial navigation, and I'm trying to determine how close to our GPS position I can get just using a sextant." Stan Kline [2]

"I'm seeing if I can find my location, the way sailors of old did. It's a hobby of mine. Care to learn more?" Sean C. [3]

"There on the side of my sextant is a timer, calibrated to the nearest second.  I have a book called an almanac which tells me the position of all the brightest objects in the sky every second of every day. Using the sextant to measure the height of an object above the horizon, and timing the measurement, I can calculate how far away the object is. Doing the same for a second object I can calculate my exact position. I'm practicing.
Along the coast is where I keep my sailing boat. When I sail it out beyond the anchored ships, the lighthouses, and the islands, to where there is nothing to see except the sea and sky, I can still find my exact position. So I can sail to anywhere I wish, any time, and find my way back again." Michael Bradley [4]

"This is a sextant. It measures angles to things in the sky. Before radio and GPS, navigators on ships and airplanes used them to find out where they were. If you know the angle to the sun, star, planet or moon plus the exact time and the body’s location in the sky you can calculate your location anywhere on earth. It's even possible to tell the time of day or night by measuring the distance between the moon and one of those bodies." Ed Popko [5]

"Trying to determine my position/location on earth." Alan S [6]





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[0] fer3.com/arc/m2.aspx/Twitter-Cel-Nav-Challenge-EdPopko-dec-2016-g37380
[1] fer3.com/arc/m2.aspx/Twitter-Cel-Nav-Challenge-Gebhart-dec-2016-g37382
[2] fer3.com/arc/m2.aspx/Twitter-Cel-Nav-Challenge-StanK-dec-2016-g37386
[3] fer3.com/arc/m2.aspx/Twitter-Cel-Nav-Challenge-SeanC-dec-2016-g37387
[4] fer3.com/arc/m2.aspx/Twitter-Cel-Nav-Challenge-Bradley-dec-2016-g37388
[5] fer3.com/arc/m2.aspx/Twitter-Cel-Nav-Challenge-EdPopko-dec-2016-g37391
[6] fer3.com/arc/m2.aspx/Twitter-Cel-Nav-Challenge-AlanS-dec-2016-g37395