>> Castor...The Orion hand controller gave a separation of 1.8",
>> but the SAC double star database gives 2.2".
Somebody needs to do some updating of files. The current specs
for Castor (from the USNO double-star site) is 4".4 in pa 59 deg.
Good test doubles for 8-inches aperture would be in the range
between 1" down to 0".6 (the Rayleigh limit). Have a look at my
"seeing test" list at:
ftp://ftp.lowell.edu/pub/bas/dbls.dat
A nice one for this time of year is the pair immediately east of
Procyon, ADS 6263, which is now a bit under 0".9. Really easy to
find. Another one that gets closer to the zenith is ADS 7307,
presently at 1".0.
\Brian
--
See message header for info on list archives or unsubscribing, and please
send personal replies to the author, not the list.