Scheduled time for Public Observing: 9pm – 11pm
Solar System Objects:
The moon will not be visible tonight.
Jupiter and Saturn will be low in the SE, rising by 11pm to 20° and 18° respectively. While too low for observation with the 20″ refractor, they will be visible with any telescopes set up outside the observatory.
The positions of Jupiters four “Galilean Satellites” are shown below at 11pm. Even if not much detail is visible on Jupiter itself because of it’s low altitude in the sky, the four large moons will be easily visible in a telescope. The other object in the illustration is a background star.
Image courtesy of Starry Night (R) Orion Special Edition, Version: 6.2.3 kcEW, Imaginova (R) Corp.
Several deep-sky objects could be observed. The examples shown below are two globular clusters (M13 and M92, in Hercules), and M57 (a planetary nebula in Lyra).
One example of an interesting binary star is 61 Cygni. At a distance of 11.4 light years, it’s the fourth closest star system to the sun that’s visible to the naked eye (barely). It consists of two evenly matched orange-yellow dwarf stars that are easily separated in the eyepiece, in a beautiful background of fainter stars. It’s proper motion (motion against the background) is visible in only a couple of years – see the video here.
Star Charts and other Information:
A very useful monthly star chart can be downloaded here from SkyMaps.com, giving information on objects visible with the unaided eye, binoculars, or telescope.
For current astronomical events see Sky and Telescope Magazine’s “This Week’s Sky at a Glance”.