Looking Up

October 2023

The “big event” for the month and, for the matter, maybe the entire season, is the partial solar eclipse on Saturday, October 14th. The path of the annular eclipse runs through America’s southwest but, here in Champaign County, we’ll experience 58% of the Sun covered by the Moon. CUAS has made arrangements with the UI Department of Physics to staff the “Science at the Market” tent on that day (details appear in the club news section). The partial eclipse begins at 10:35am and mid-eclipse is at 11:58am. The entire event is over by 1:25pm. Please join us at the market as we educate people on how to properly (and safely) observe the eclipse. We can retrieve the solar equipment from the observatory and use it at the market. We begin October with the Moon and Jupiter near each other. Look in the eastnortheast as the pair, separated by 2 degrees, rises around 9pm. This arrangement nearly repeats itself at the end of the month as the two are separated by 3.5 degrees on 28th. The phase of the Moon is not the same but recall this is the difference between a “synodic period” (depends on the Moon’s appearance – about 29.5 days) and a “sidereal period” (depends on Moon’s position among the background stars). There is a partial lunar eclipse on the 28th but we’re on the wrong side of the Earth to see it. The umbral eclipse is done by the time the Moon has risen. Saturn had an opposition last month so it is already above the horizon as the sky darkens this month. At magnitude +0.5 it’ll be the brightest thing in the southeast as it sits in the relatively star-poor area of Aquarius. A waxing gibbous Moon is near Saturn on the 23rd . Jupiter rises just after 7pm in mid-October in the eastnortheastern sky. At magnitude -2.9, it will easily outpace Saturn in brightness – you can’s miss it! Venus graces the morning sky, rising at roughly 3:30am. Venus has entered the boundaries of Leo and will slide past the heart of the Lion, the star Regulus this month. An interesting alignment presents itself on the morning of October 10th. Not only is Venus closest to Regulus, but a waning crescent Moon is on the other side of the star. Why not look at 5:30am? Greatest separation from the Sun occurs on the morning of the 23rd . And we have good conditions for the Orionid Meteor Shower this month. Twice a year, our Earth passes through the dust trail of Halley’s Comet, once in May and then again in October. The dust particles of the Orionid shower enter the atmosphere at something like 140,000 miles per hour, but then slow down, giving up their energy to the air, which momentarily glows. One may see 15-20 meteors per hour after 2am on the morning of October 22nd . -DCL