What’s the Sunspot Number?

By Bill Pellerin

Object:  The Sun
Class: Star
Magnitude:  -26.74
Size/Spectral:  Diameter = 109 x Earth diameter; G2V
Distance:  93 million miles
Optics needed: See links below for observing information

You might be surprised to find out that the ‘Sunspot number’ for any given day is not simply a count of the number of visible sunspots. As with many things in science, it’s not that simple. The sunspot number is calculated using the simple equation:

R = (10*G + S)*K
Where:
R = the sunspot number
G = the number of sunspot groups observed
S = the count of all sunspots in all groups
K = a scaling number to compensate for variables (see text).

So, in the end, to calculate the sunspot number you’d count the number of sunspot groups and multiply that number by 10. You then add the result to the number of individual sunspots in all groups, and finally multiply that result by K. …

More Info … 

by Rene Gedaly

OBSERVE SELFISHLY. JOIN AN OUTREACH EVENT That’s right. By giving others a look through your scope, you’ve carved out precious time for your own observing. It attracts the community, sure, but it also keeps your own skills sharp. Or maybe you don’t know your way around the skies or don’t have your own telescope. Show up and look through what’s already there and find out which type of telescope you do like. It’s like speed dating the loaner telescope program and the scopes are lined up for you.

ART IN ASTRONOMY: MEMBER PHOTO GALLERIES One of the things you miss as a website lurker is the personal photo galleries of HAS members. The post-processing required of the imager takes the work and skill of a day job and so far, I haven’t succumb. Still, it doesn’t keep me from appreciating the artistry of many of our members. If you’re a member, log in and see what your clubmates are doing. If you’re not a member, dues are pro-rated your first year, so now’s a great time to try us out. Click the Join HAS tab on the website.

by Mike Edstrom

The roof is now on and one of the a/c units is installed so inside work can begin in comfort. Hopefully we can get the insulation installed and then the siding done soon. We will continue updating the process as milestones are achieved.

Please watch the web site for future announcements as the training sessions on the new MX and 12” RC scope in the observatory which everyone that has been trained on using the observatory must take has been finalized and will be announced soon.  

Summer constellations are up and waiting for you at the Columbus Dark Site, hope to see you there soon.

by Bill Pellerin

OBJECT: HD 140283, HIP 76976
CLASS: Metal Poor Sub-Giant Star
CONSTELLATION: Libra
MAGNITUDE: 7.26
R.A.: 15 h, 43 m, 1.86 s
DEC: -10° 56’ 5.62”
SIZE/SPECTRAL: F3
DISTANCE: 190 ly
OPTICS NEEDED: A small telescope, binoculars

Here’s an odd one. I first heard of this star while watching a Great Course lecture in the series ‘The Life and Death of Stars’ by Keivan Stassun. Interestingly, to me, I had never heard of this star before, but it may be one of the more fascinating stars in the sky. The very early universe had much smaller quantities of the heavy chemical elements in it. Why? Because the heavy elements are created (fused, actually) in stars, and in the early universe there had not been enough time for stars to form, live their lives, and seed the universe with these heavier elements. Why? Because the heavy elements are created (fused, actually) in stars and in the early universe there had not been enough time for stars to form, live their lives, and seed the universe with these heavier elements. By ‘heavier’, I mean those elements in the periodic table beyond hydrogen and helium...