[time-nuts] Sidereal time
Lux, Jim (337C)
james.p.lux at jpl.nasa.gov
Fri Jan 15 17:21:47 UTC 2010
On 1/15/10 9:13 AM, "J. Forster" <jfor at quik.com> wrote:
> Heresy:
>
> Why do you really NEED super accurate siderial time? If you are using it
> to point a telescope, you only need it accurate enough to get the guide
> stars into the field. Remember, the atmosphere refracts kinda randomly.
>
> -John
>
> =
Celestial Navigation? Essentially, one determines longitude by figuring out
what the difference between local solar time and sidereal time is. Now, what
is super accurate? 40,000 km =24hrs, so 1 second is about 460 meters.
More information about the time-nuts
mailing list