Did you know you can check out telescopes at the Library?

Orion StarBlast 4.5" TelescopeThanks to a generous donation from the Louisville Astronomical Society, LFPL is excited to offer telescopes for check out at the Southwest and South Central Regional libraries. The lending period is for one week and is limited to Louisville Free Public Library cardholders in good standing, 18 years or older. Signing a Telescope User Agreement at the time of checkout is required. Go to the Library Catalog to reserve one today.

For more information on the telescope lending program, visit:

September in the Sky
By Frank Nelson, Sidewalk Astronomy Coordinator for the Louisville Astronomical Society.

Welcome to the final month of summer! August turned out to be a very nice month weather-wise, the first “normal” summer we had in two years according to my notes. I hope you got to go out and do some stargazing!

September is a month of transition from the bright summer Milky Way to the dimmer skies of fall. We still have some good targets to look at. Binoculars are all you need to see the star clusters in the bright band of the Milky Way. If you have a 4” or larger telescope, I have a couple of easy to find treats for you this month.

I’ll start in the constellation of Lyra. The brightest star in Lyra is Vega, the fifth brightest star in the night sky and almost directly overhead at sunset. After Jupiter and Saturn, Vega will be the first star to peek out of the twilight. Vega is a bright, white star and only 25 light years away making it a local neighbor of our own sun. Find Vega, and you will notice a rectangle of dimmer stars underneath. There is a fainter star to the north-east, closer to Cygnus, names Epsilon Lyrae. This is the famous “Double-Double” star. In binoculars, Epsilon will show as two stars roughly equal in brightness. In a 4” telescope at moderate magnification, the same system of stars will show that each of the “doubles” is in fact two stars! Try to get 130x magnification on this star. If you can easily spit the pairs, the skies are calm above you and it will be a good night of observing! Sheliak, also known as Beta Lyrae, is the brighter star in the rectangle, furthest from Epsilon. It too is a double, in a busy star field. Aim at Sheliak with your telescope and center the star. Sheliak is a variable star; every 13 days a dimmer companion crosses in front of the brighter star reducing its brightness. Watch this star over a few nights if possible and see if you can notice a change in brightness. Now, slowly move your telescope to the other bright star in the bottom of the rectangle. Roughly ½ way between the two will be a fuzzy, dim glow about the same size as Jupiter in the sky. This is the famous Ring Nebula, M57. Easy to find, easy to see and it takes high magnification well. If you can split the “Double-Double” from above, use as much magnification as you can. If you are in light polluted skies, try to use less magnification at first; this will concentrate the faint glow of the ring. More magnification will darken the sky around the nebula once you find and center it. With Lyra nearly overhead, this is the best time to view this area of sky!

Lyra Consellation

Nearby is one of the prettiest double stars in the whole northern sky. Alberio is a fan-favorite for the bright contrasting colors of the two stars. Alberio is a brighter star, visible even in moderate light polluted suburban skies. Alberio comes from the Arabic word for ‘The Beak” and represents the head of Cygnus the Swan. In the star chart below, I have labeled Alberio for you. And since you are in the area, one final target. M27, the Dumbbell Nebula is not that far away. If you keep going in a line made by the rectangle in Lyra, through Alberio, you will see a very small, faint constellation called Sagitta, the Arrow. Draw a line in the sky from Alberio to Gamma Sagitta (a red giant star in a field of white and blue stars) at the point of the arrow, then slowly work your way from Sagitta towards Alberio. About 1/3 the way there you should see a triangle of fainter, barely naked eye visible stars, in the blue circle. This line is roughly 10° wide, or about the size of your fist held at arm’s length. This is about double the size of the field of view of most binoculars. One star is a double, move in that direction. As you move toward the center of this triangle, you will start to see a large, faint, fuzzy glow. This is the famous Dumbbell Nebula. I see it as more of an apple core shape, but at medium magnifications (80x to 100x power) you can make out the lobes seen in photographs. Finally, for a challenge, notice that yellow dot labeled M71? M71 is a cluster of stars in front of a very dense part of the Milky Way. With patience and dark skies, and low magnification, you may be able to make out a denser knot of stars against the background glow of the Milky Way. You will need dark, clear skies to make you the shape of the cluster!

Lyra Consellation

Star maps and current information from the Astro League.

For more star charts on the summer milky way Messier targets and Summer objects, check out this website.

Thanks for reading and clear skies!

Last Updated: 09/03/2019