My OperaZero Degrees (Almost)
Sunday, January 30, 2011 7:22:58 PM
Unlike my last post where Zero Degrees may have been referring to the temperature (although it was near 0C today), this time it refers to my location. As an Engineer, calibration of devices is important to me. A device is only as accurate as it's calibration. Kim gave me a new GPS for Christmas so I decided I needed to calibrate it before putting it to use. I already had an uncalibrated Garmin Nuvii for driving, but the new one was for sledding. They were both in agreement at home, so I figured they were accurate until.......
I was late for my arrival at the Royal Observatory. While planning my trip, the Underground schedule said I would arrive at 12:45, well in advance of the 1:00 ball dropping. However it appears the Her Majesty's Tube does not run with the same precision as the Observatory. I was over an hour late due to train breaksdowns and delays, and my trip was only supposed to take an hour.
The ball on the mast at the observatory is raised half way up at 12:55 every day. It is raised to the top at 12:58 and at precisely 1:00 pm GMT it drops.
At the precise instant that the ball starts to drop, the sailors in the Thames below would set their chronometers, to allow them to correctly navigate the seas. Precise timekeeping is essential in plotting longitude. The Thames can be seen just over Queen's House (more on that in the future). Presumably every day there would have been a traffic jam of ships waiting to sail for a colony or two. When my grandparents came over to Canada by boat, it was still navigated with a Chronometer, although it would have been set to an electric or wireless standard.
There is an official sculpture that you can stand in front of to get your picture taken. On my arrival at the Observatory, the line was about 15 minutes I estimated. As it was a cold day, I decided to tour the Museum of Timekeeping, and sure enough, when I came out, the line had swollen to over an hour.
Oh, well, I stood on the Prime Meridian, just behind the sculpture and fired up my GPS. To my horror, it did not say 0 00' 00''
I checked the sign on the observatory in front of me, and yep, this was the big Zero.
I tried the Sat Nav version, and it gave exactly the same result. WTH (Emily might read this so I didn't use the F). I don't know how to change the sat nav from Decimal Degrees to DMS, but with my limited math skills, I figured that the latitude was pretty much spot on and the first GPS was in latitude agreement.
I also noticed that the elevation was in error, by about 30 feet, albeit I was about 6 feet higher than the Newlyn Line, when I checked the reading.
I eventually discovered the reason for one of the errors, but not the other. However I have to go to bed, so I will leave you in suspense for now.
Cheers
Only a bit lost Bryan
I was late for my arrival at the Royal Observatory. While planning my trip, the Underground schedule said I would arrive at 12:45, well in advance of the 1:00 ball dropping. However it appears the Her Majesty's Tube does not run with the same precision as the Observatory. I was over an hour late due to train breaksdowns and delays, and my trip was only supposed to take an hour.
The ball on the mast at the observatory is raised half way up at 12:55 every day. It is raised to the top at 12:58 and at precisely 1:00 pm GMT it drops.
At the precise instant that the ball starts to drop, the sailors in the Thames below would set their chronometers, to allow them to correctly navigate the seas. Precise timekeeping is essential in plotting longitude. The Thames can be seen just over Queen's House (more on that in the future). Presumably every day there would have been a traffic jam of ships waiting to sail for a colony or two. When my grandparents came over to Canada by boat, it was still navigated with a Chronometer, although it would have been set to an electric or wireless standard.
There is an official sculpture that you can stand in front of to get your picture taken. On my arrival at the Observatory, the line was about 15 minutes I estimated. As it was a cold day, I decided to tour the Museum of Timekeeping, and sure enough, when I came out, the line had swollen to over an hour.
Oh, well, I stood on the Prime Meridian, just behind the sculpture and fired up my GPS. To my horror, it did not say 0 00' 00''
I checked the sign on the observatory in front of me, and yep, this was the big Zero.
I tried the Sat Nav version, and it gave exactly the same result. WTH (Emily might read this so I didn't use the F). I don't know how to change the sat nav from Decimal Degrees to DMS, but with my limited math skills, I figured that the latitude was pretty much spot on and the first GPS was in latitude agreement.
I also noticed that the elevation was in error, by about 30 feet, albeit I was about 6 feet higher than the Newlyn Line, when I checked the reading.
I eventually discovered the reason for one of the errors, but not the other. However I have to go to bed, so I will leave you in suspense for now.
Cheers
Only a bit lost Bryan
slackwrdave # Monday, January 31, 2011 2:07:36 AM