On 07/09/2015 01:44 PM, Clifford Heath wrote:
On 10/07/15 12:07, Phil Hobbs wrote:
On 7/9/2015 9:14 PM, Jeff Liebermann wrote:
It would be a major disaster if a leap second were
thrown into the timing if you're tracking a spacecraft such as Voyager
1 moving at 17 km/sec (38,000 mph).
You'd be off by 17 km. Is Voyager 1's position known to that accuracy?
Didn't think so.

And yet if you were aiming at Pluto via a slingshot around Venus, you
don't want to be 17km off on approach to Venus. I can't do the math, but
I suspect it's rather closer to 17cm.


Well, you probably aren't using your computer's clock to do that
measurement anyway. Astronomers and orbital mechanics bods are used to
having to worry about different types of time scale--ephemeris time,
UT1, UT2, UTC, and so on.

The movement to abolish leap seconds is just another special interest
group.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
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ElectroOptical Innovations LLC
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