Cool, calm and collected

[RobertI]

 A lovely night last night, perfect temperature, no wind, transparent skies and excellent seeing. Had a lovely and, as usual, short session with the 102ED-R. I sat back in my observing chair and looked at my prepared list of in SkySafari. I am a recent convert to seated obsering and I find it really helps to calm things down, encourage me to take my time and think clearly.

First stop was Izar (Epsilon Bootis). I've been seeing this one a lot lately in a smaller 66mm scope and it was lovely to see it easily split with the larger aperture. Just below Izar was HR5524, a lovely double separated by 2.2", very close together at x100, and at x200 revealed a blue white primary and white secondary. Now across to Xi Bootis, probably my favourite of the evening with a bright white primary and a stunning golden yellow secondary just 5.5" away. I found this was nicest at x100 with both components pin sharp like tiny ball bearings. The scope was working well tonight. On to the nearby Pi Bootis, another fine double very similar in size and brightness to Xi, but without the colour difference.

Happy with my successes I thought I'd try something more challenging - Zeta Herculis, with two components of mags 2.8 and 5.4 separated by 1.5". Even at 200x I could only just make out a brightening of the first diffraction ring at the correct PA, but nothing better, not helped by scudding clouds. However I had better success with HD136176 in Corona Borealis comprising two mag 7 stars separated by 1.6". Easy to find and just split at higher mags.

Finished with a quick look at the double double (both nicely split at 100x) and Alberio rising in the East.

I think my doubles observing list will keep me going all year! I created it by filtering on doubles which are between 1.5" - 10" and magnitudes 2 - 8. The result was a LOT of doubles. The constellations with the most targets seemed to be Bootes, Hercules, Cygnus, Orion, Ophiucus and Taurus. It was also interesting to see that Lynx had a lot of doubles, which was surprising given that it is a very faint constellation with relatively few bright stars.

Edited May 11, 2021 by RobertI

[John]

Nice report Rob

Zeta Herc can be a really tricky blighter to split. The secondary star can look like a "bump" in the diffraction ring rather than a definite star. Like a thin snake which has swallowed an orange

 

 

[Stu]

Good stuff Robert! SkySafari is very useful for creating dedicated lists like that, and I love the ability to show them all on the chart.

Sounds like you got Zeta Herc ok! That’s about how I see it in my 4” scopes, it seems to need a bit more aperture (or exceptional seeing) to resolve both airy disks.

[SuburbanMak]

Thank you - I’ve grown to love reading about new seasonsble doubles to look for & there sound like some super targets here - great report! 

Edited May 13, 2021 by SuburbanMak

[Paz]

Nice report, I agree doubles are great targets, easy to observe all year round, you don't need a dark site and there's so many you can always find good ones that are easy to star hop to.