Backyard OR - Nu Scorpii

by Mark Bracewell

Backyard is never grab and go for me, there's always some neighbor light or tree or something to deal with. I found a spot beside the house that gave me about 15 degrees of SSW sky and propped up some left over sheets of plywood from a garage re-roof just completed to block out the worst of the intruding lights.

Seeing was variable, 6/10 pickering at best fleeting moments, but the dim pair easily split and the closer bright pair obviously double, though never cleanly split @ 270x. Given the seeing, I'm sure the view would have been improved in the 4" - I think I need to make an aperture mask for the 10" for situations like this one.

Anyhow, I popped from Jupiter to Nu back and forth for about 45 mins in case either target had a great seeing moment. Jupiter looks very different from the last time I looked at it (a long time ago), the NEB very wide, with a couple of swooshes like water-ski wakes coming off it, a couple of equatorial stripes and a dim SEB, the rest pale and washed out, swimming on the limbs, but still nice to see. I had hoped to see some milky way from this new spot by the house as it rolled into view but it was not to be, the moon was coming, M9 was just a dim smudge, so I looked at M24 for a bit and packed it up.

So there remained this mystery about what Mark had read about Nu in Burnham's:

'I know I've split the pairs, but years ago. I was surprised reading in the text Burnham writing "I requested Professor C.A. Young to examine it with the splendid 9.4 inch Clark refractor of the Dartmouth Collect Observatory. He examined it several times, and at last when the air was very steady could not even notch it.."'

Alexander had it - the quote was from S.W. Burnham in the 1870's. The older Burnham had first discovered the A-B pair with a 6" for which he received many kudos at the time, and no small feat either, as the WDS catalog has the A-B separation in 1873 as 0.3" ( and 1.3" in 2003 which is why we can split it now. Interestingly the PA is little changed, we must be roughly in the plane of its orbit, this'll be a fun pair to watch over the next few centuries ;-)). I couldn't find a reference which gave this pair's period, anyone have an idea?

There are interesting stories aplenty around Prof. Young and the 9.4" Clark scope - in 1872 he took the 12 foot long beastie all the way to Wyoming to, among other things, conduct experiments observing through polarizing filters (hey Richard!). Next time I'm whining about moving a 40 lb. scope I need to remember that ;-)