Re: [time-nuts] Sidereal time

[Lux, Jim (337C)]

On 1/15/10 9:13 AM, "J. Forster" <j...@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

What if it's a *radio* telescope? Or a DSN dish? Both of those have to track
sidereal motion.  At Ka-band, the 70meter dish needs pointing on the order
of 1 millidegree.  That's about 250 milliseconds, I guess.


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