Movement in Binaries

[Tropo-Bob]

I observed the easy double Gamma Virgo last night. It was not so easy 20 years ago when I scrambled to have a look at the rapidly closing divide. Then for many years, nothing, except a signal star. There is indeed movement in the heavens!

This is the fourth binary where I have seen movement. Many like me, will have observed Alpha Centauri become much closer over the years.

Some binaries have become easier though. When I first observed in the late 1960s, I also swung my 60mm scope to observe the easy double Castor. It unfortunately was lousy timing, as it was near it minimum separation during its 400-odd hundred year orbit. Now of course, it is easy. I also had a similar experience with 70 Orp, from the 1970s.

[Tinderboxsky]

Very interesting. I regularly target transient events to observe as I too enjoy detecting "movement in the heavens". But I don't have the long observing history you have to be able to detect long period movement in binaries. All the more reason to stay alive.

Steve.

[bigjoe]

Hi Bob , Steve.
Yes ...some like Zeta Herculis are getting easier over the recent years, and by 2023 will be over 1.5" apart!!
According to stelledoppie its separation is about 1.25 " currently ; so tough!!.
Will try it again in an etx125 , 4" ed ? , in next few days..weather permitting ; should be a good test in that 115 ed!!
Can of course do it in 254mm SCT and c8 .
bigjoe.

[Merlin66]

http://www.astrosurf.com/hfosaf/

If you're into double stars and use webcam/ fast frame type cameras then you really should visit Florent Losse's page on double stars.
Highly recommended.

[Tinderboxsky]

Hmm ... I am far too far south be be able to separate Zeta Herculis. A 1.3” separation with a delta magnitude of 2.5 is definitely achievable at higher elevations with my 140mm refractor but I will have to pass on this one.

Steve.

[tonybarry]

You guys would love occultation observing. That's very movement oriented. Asteroid eclipses star. Time the disappearance and reappearance. Send results to RASNZ Occ Sec. ... good fun and gets orbital elements improved for asteroids.

http://www.occultations.org.nz/videotime/manual.htm

Regards,
Tony Barry
WSAAG

[bigjoe]

Thanks for this Ken I'll have a look.

[bigjoe]

Yes Steve ; it is a little far north at +31°!
bigjoe

[bigjoe]

Thanks also Tony will have a look at this.
bigjoe

[Tropo-Bob]

A great suggestion and not too far north for me!

Thanks everyone for all these great ideas. I retire in about 10 weeks and will finally be able to spend more time on my hobby.

[gaa_ian]

That's great news you get to retire soon Bob ! Maybe we could get together to do a FNQ astronomy night again ?

[el_draco]

Alas, I have seen way to much of Alpha Centauri's orbital change :(