Has anyone seem Gamma Andromedae C?
Posted 04 October 2013 - 11:03 PM
Can ANYONE here see gamma Andromedae C? Even a bump?
Thanks in advance.
Posted 06 October 2013 - 08:03 PM
The ephemeris (6th orbit Catalog) gives ~0.1" and closing at present; down to 0.02" (yep, 2/100 of an arc second) for 2015.0; so getting back to the realm of likely amateur observations will be a few years away yet.
Running a version of the orbit ephemeris (estimate, not claimed dead accurate), the pair will hit 0.2" by 2020 (within reach for David Gray and Christopher Taylor and...who else???); 0.3" around the end of 2022; and will reach 0.4" by 2027. Widest separation, just over 0.5"/approaching 0.6", will be in the 2040s.
The fun is finding at what stage of the orbital widening it can be seen double with a particular telescope. An 8-inch will likely show it as a bare contact pair (Dawes Limit effect) by the late 2030s. The 8-inch, for a 0.5-Rayleigh elongation (~0.35") can make the attempt in 2024, a much shorter wait. To match David Gray's view of A2145, well elongated at 0.17", that'll be the separation for Gamma And BC in late 2018 - only 5 years away.
And to make it a bit easier, the stars are not hugely different in brightness - delta-m ~1.2 - more like Chi Aquilae than - ummm... - BU 67 in Cygnus (Dm ~3.0) or 90 Her (Dm 3.5) - to not mention the "he who must not be named" pair.
Posted 07 October 2013 - 07:22 AM
Looked two nights back in 8/10 seeing -quite round!
Posted 07 October 2013 - 07:37 AM
So its not even hinted at with a 16" - oh well - such is an orbit.