Scheduled time for Public Observing: 8pm – 10pm

Tonight is International Observe the Moon Night!

Solar System Objects:

The Moon: will be 24° high in the SW at 8pm, and 53% illuminated (First Quarter phase). Public observing has been scheduled this year to ensure that the moon will always be visible. It is a richly detailed and ever-changing object to observe, due in part to the motion of the terminator (boundary between day and night) moving across the face of the moon.

Image (c) Virtual Moon Atlas / http://ap-i.net/avl/en/start

As the shadow boundary moves along, various craters and mountain ranges are brought into sharply detailed relief. And even when sky conditions are less than perfect, the moon will still be well visible through high thin or broken clouds.

Planets: Saturn will also be 24° at 8pm, very close to the moon. In binoculars or a very wide-field telescope, they will both be in the same field of view.

Image courtesy of Starry Night (R) Orion Special Edition, Version: 6.2.3 kcEW, Imaginova (R) Corp.

Somewhat more challenging, but easily visible in the 20″ refractor, the planet Neptune will be 26 degrees up in SE at 8pm, and rising. Even at it’s distance of about 2.8 billion miles it is visible as a planet (not just a star-like point) in the telescope, and it has a unique blue color. Four times the diameter of the earth, and 29 times it’s distance from the Sun, it takes 165 years to complete an orbit.

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”.