A Wide Double (Eta Peg) Between Clouds

[cloudsweeper]

Allowing optimism to get the better of me, I set up the Bresser Dob, just hoping to sneak brief views of just about anything that came into view between clouds.  And so it was.  

The glow of the Moon (approaching full) could be seen in cloud above a rooftop, then a little later it peeped over the roof and I got it in the RACI finder, with most of it in the EP.  Minutes later, all of it, a beautiful sight at x64/1.29 deg.  But only very briefly!

I had similar brief encounters with M13 and M31, both spotted by simply aiming for them with the Rigel, guided also by the RACI.  Satisfying at least to know that tracking things down can be quite quick and easy.

When the Great Square Of Pegasus was clear in the east, I targeted Eta Pegasi (Matar) above it - a double, according to Stellarium.  (Many such named doubles are not actually visual, so do not feature in Haas and CDSA.)  A faint companion was very easily seen at x35, with a wide separation - I estimated about 2 minutes - so it really just looked like a fieldstar.  This at least was something new, with (as is almost always the case) some interesting background science.

It turns out that each of the stars is a double, too close to split visually, and the two pairs are 6000 AU apart, with an orbital period of about 170,000 years!!  The separation on the celestial sphere is about 94", so my estimate was not too terrible!  Sissy Haas has this one listed.

Then the rain started so I hurriedly got everything back in the astro-shed.  Nothing spectacular, but nevertheless an enjoyable hour!

Doug.

[John]

Good stuff Doug

I've had a session a bit like that - glimpses in cloud gaps of a few nice things.

Better than the telly though !

[Paz]

Nice report. I've been watching the clouds and put the C8 out to cool but in the end the clouds didn't clear enough and I didn't go out.

[domstar]

A good read. You always seem to make the most of your opportunities.