Scheduled time for Public Observing: 8pm – 10pm
This is Wesleyan University Homecoming Weekend, so there will be more campus activity than usual. As always, there is no parking at the Observatory, but it should be available at either the Vine St. or Wyllys Ave. parking lots. Although closer to the Observatory, using the Vine St. parking will require climbing a long flight of steps.
Solar System Objects:
The Moon: will be 18° high in the SW at 8pm, and 36% illuminated (Waxing Crescent phase). At this altitude, it will only be visible from outside of the observatory, and only for a short time.
Image (c) Virtual Moon Atlas / http://ap-i.net/avl/en/start
Planets: Uranus and Neptune will both be observable with a telescope tonight.
Neptune will be nearly due South at 9pm, at an altitude of 42 degrees. It’s distance is about 2,730,000 miles, or 29.4 AU (Earth-sun distances). It’s 1,680 mile diameter moon Triton may be visible in the 20″ refractor, but will require careful observation to see it.
Uranus will be farther to the SE, at an altitude of 39 degrees. It’s a little more than half as far away as Neptune, at about 1,750,000 miles or 18.8 AU.
Both planets are approximately 4 times the diameter of Earth.
Although the planet Saturn will not be visible tonight, an interesting object that could be observed is the Saturn Nebula (NGC 7009). It’s classified as a “planetary nebula”, not because it has anything to do with planets, but because this type of object often appears small, round, and with a high surface brightness, so that when first discovered they almost looked like planets. They are actually caused by sun-like stars which, when highly evolved, eject their outer layers in shells on their way to becoming white dwarf stars. See the video from the European Southern Observatory.
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”.