On Jul 4, 2012, at 3:29 PM, Jason Hellenthal <jhellenthal@dataix.net> wrote:
Yeah but what you don't understand is that manual navigation after a certain point of difference becomes inaccurate to a degree that is unacceptable by most military standards.
Manual navigation (sextant, etc) is dead. It's not taught for new pilots or mariners / navigators. A few hobbyists still learn that, but they can easily keep a solar-true time clock around if they wish. Maintaining any time standard for that purpose is not supported. It's no reason for the timekeepers, nothing we need to care about. The few navigation systems that look at the sun and stars have - and inherently need - better time reference than the allowed 0.9 sec before we leap. They already handle this internally. That 0.9 sec max error comes to up to about 400 meters for equitorial surface nav or 6500 for orbital objects (or suborbital - cough). Already unacceptable... George William Herbert Sent from my iPhone