Have You Split Beta Muscae?

[EpickCrom]

Hi fellow Astronomers! I would like to hear from anyone who has split Beta Muscae. This star has defied me time and time again. Seperation is listed as 0.8" with similar 3rd magnitude components.My latest failure was a few minutes ago:eek: I use a 10 inch dob. So have you ever split this star and with what aperture scope? Has anyone split it with a 10 inch?

Joe

[Tropo-Bob]

I have also found Beta Musca difficult to split, however, last year I was able to split it with a 140mm Vixen Achromat.

In a thread about Antares B, this is what I wrote last June:


...However, last night was special as the evening had very good seeing. It was an unusual day with Cairns having fog in the morning. That is a rare event here.

So flushed with success, I tried to split Beta Musca, which I have been trying to do for the last 30 years with many different scopes. With 230x, I could see the discs were overlapping, but not separated. At 265x, I could see the discs were close and was not sure if they were separated. With 320x, I had to patiently wait for moments of better seeing and then I could see that they were separated. At 400x, it was too much power and it was never clear enough to see anything.

I am delighted; I never expected to ever see Beta Musca split.

I started to think of more difficult splits, but the clouds rolled in about 8.45pm and ended the evenings viewing.
__________________

[ngcles]

Hi Joe,

Observing note from 25 February 1999 on a night when I rated the seeing at 7/10 (good but not great).

R207 Double star Musca
25cm x363: Brilliant pair but quite close. Split but difficult at x276, no problems at x363. Both are cold white or bluish – close, 1-1.2" in PA 30, only 3/10ths of a magnitude in difference between the components, 3.8 4.1?? Very beautiful. Showpiece.

A measure I saw elsewhere on the net in 2007 was 1.0" in PA 50. Apoastron was in 1954 at about 1.5" and they are currently slowly closing.

Hope that helps.

Best,

L.

[EpickCrom]

Hi TroppoBob, nice report! Glad you finally split Beta Muscae last year, it's a tough one for sure. I am inspired by your success and will try again on a night with good seeing. Thanks

[EpickCrom]

Thanks for including your observing notes Les! Beta Muscae sure sounds lovely once split! Great job resolving it, armed with your knowledge I will try to split it again on a night of "perfect" seeing. Thanks

[glend]

I too have split Beta Muscae, with a couple of different scopes. First was with my GSO 16" f5 Dob back in my Bretti dark site days; the second was with my GSO f12 Cassegrain in perfect conditions in my observatory. I have tried with my ED150DX f8, and could just see a hint of an hour glass gap, but the conditions were not ideal, and it maybe beyond that scope.

[EpickCrom]

Great job splitting that toughie Glenn! I will keep trying. Thanks and clear skies to you.

[EpickCrom]

Hi fellow observers!

Well I'm pleased to say that I finally split Beta Muscae last night! Seeing was excellent and Beta Muscae was pretty high up, these factors no doubt assisted me greatly.

I used my 3.5mm Saxon SWA eyepiece in my 10 inch dob for 343x. I detected two perfect, equally matched, blue balls of light extremely close together. Using my 2x barlow for 686x confirmed the split with a very tiny black line seperating them. Perfect airy disks surrounded the two stars. Woohoo! I was very pleased to finally split this tough double. At 0.8" this is my tightest split yet, and the first time I have split a sub 1" star.

Clear Skies
Joe

[Rod-AR127]

While l won't be matching your split, tonight looks like a great viewing night again here in Perth for my first viewing session in well over 6 months.
No clouds, no smoke, no wife.

[EpickCrom]

G' Day Rod!

Yes, it's looking like it's going to be a good night. Have fun observing and enjoy :thumbsup:

[gaseous]

LOL, the unholy triumvirate for the visual enthusiast....

[Rod-AR127]

I'm sorry for saying no clouds...
I won't do it again and l have all night on the couch to think about it.
Sorry.

[Steffen]

I’ve split Beta Muscae many times with a 6” Mak, but it requires good seeing. In fact, I used it to gauge the seeing of a night, when it was high enough.

In the 6” Mak, the first diffraction rings would touch, but the Airy disks were clearly separated. That was about 5-10 years ago.

[PLR]

I have not been successful in splitting it with my 8" SCT but I will give it a try tonight again seeing that we have a Waxing Gibbous 75% moon, the good news is that the separation is increasing so it should become easier over time as this graphic suggests....

[EpickCrom]

Thanks for sharing your experiences with the wonderful Beta Muscae!

Keep em coming..

[Finbar]

I have not tried this yet; relatively new to doubles, and conditions at home for past two years have been so bad I've seen very little of anything.

But I'm a perplexed. I mostly check Stelle Doppie (using Washington Double Star Catalog), but noticed the plot image there is quite different from Piet's. Wikipedia provided a link to http://stars.astro.illinois.edu/sow/betamus.html (written in 2010) whose plot agrees with Piet's.

The period differs too: about 194y vs 459y ±191 - so c. 269 to 650 years!

So in the end I am a little confused, and wonder where the rest of you consult.

Where sources thus far seen all agree is that the gap is closing. Stelle Doppie reports current separation of 0.956", hence some round it to 1", but somewhere reported 0.93". It seems to me there is as yet considerable uncertainty, except for agreeing that they are a physical double and that viewing is a challenge.

I look forward to giving it a try, if my skies ever clear.

[PLR]

Thanks Barry for bringing that to my attention, I found this article, by Dave Blane, on an ASSA website : http://assa.saao.ac.za/sections/double-and-variable-stars/double-stars/news-and-articles/double-star-challenge-beta-muscae/
He agrees with the 194 year period, Robert Burnham jr states that the period is still uncertain (+- 1978) and its separation in 1880 were 0.6" and 1.6 in 1955, Stellarium gives it as 1" in 2019 so it looks like its getting smaller?!

PS I did give it a try last night but conditions were not good, it had a lot of "moving hairs" around it but I am sure I saw two distinct dots in the center of the noise...This was with favourite double splitter: a TV big Barlow with a 10mm super MA eyepiece in a 8" SCT giving the most I can hope to get from my SCT : X400 with a 0.5mm exit pupil.

[EpickCrom]

I use Sky Safari 6 Plus which lists Bets Muscae's current seperation as 0.8"

[gaseous]

Tried to split Beta Muscae last night in better than usual seeing conditions here in Brisbane with my 8" dob, but failed miserably. Even at 400x there was no hint of it being a double star, let alone any perceived separation. I'll be attempting it every time I have a scope out from now on though.