Click here for Dave's preview of sky events in 2016.
For: July 18-24
I have a challenge for you this week. Using binoculars, when can you first see Venus? Venus passed behind the Sun in early June and now slowly moves out from behind its brilliance. Venus sets just after the Sun, so you will need an unobstructed horizon. Look in the west-northwest just after the Sun sets. Also this week, Mercury will appear above and to the left of Venus, though Mercury will appear much fainter. Venus and its highly reflective clouds will be easier to see each evening, but its rise out of the twilight is gradual. It won’t set in a dark sky until the fall. Give it a shot and let us know at firstname.lastname@example.org when you’ve seen it!
For: July 25-31
One could say “meteor season” begins this week. Though there is no official “season,” you’ll start to see a few more “shooting stars” in the sky. Meteors are bits of dust in space, roughly the size of a pencil eraser. When they slow down in the atmosphere, their energy is transferred to the air, making it glow. When the Earth encounters a stream of dust, usually left by a comet, we have a meteor shower. The Delta Aquarid and the Alpha Capricornid showers are expected to peak this week. Though the meteors enter the atmosphere at roughly parallel trajectories, to us they appear to emanated from a spot in the sky called the “radiant.” This is how the showers inherit their names.
For: August 1-7
The New Moon occurs tomorrow night, meaning we’ll have a beautiful crescent in the western sky by the end of the week. Thursday night, the Moon is just below and to the left of Mercury. Friday it is below Jupiter. Also Friday the planetarium opens a fulldome show on the light spectrum entitled “Cosmic Colors” at 8pm. Saturday evening you have a choice as there is an open house at the CUAS Observatory (cuas.org) and I’ll be giving a presentation and doing some telescope observing from the Middle Fork Forest Preserve. Both events start at 8pm and are weather permitting. If it’s clear, why not take in the August sky? You might even see a few meteors!
For: August 8-14
The planetarium is closed for a few days as we replace our 30-year-old seats. If you’re interested in purchasing one of our old seats, see our web site. Saturday, the CU Astro Society does solar viewing at Market at the Square in Urbana (8-noon) and then hosts another open house Saturday evening. The big event of the week is the Perseid Meteor Shower, peaking Thursday and Friday. This year’s event has the potential to be more intense than usual. And you need no special equipment! Find the darkest sky you can and set-up a blanket so you can see the sky above and then be patient. The morning hours are favored though you may see meteors at any time.
For: August 15-21
We have lots of celestial stuff passing other celestial stuff this week and next. Mercury is furthest from the Sun (from our point of view) Thursday, but it still sets in the evening twilight. Look Friday, though, as Mercury can be seen below Jupiter very low in the west. Add in Venus to the right and they make a nice triangle. If you keep watching the trio, Mercury will seem to move closer to the Sun and Venus and Jupiter will converge. Look soon after sunset with binoculars. Saturday is Decatur’s “Astronomy Jam” at Friends Creek Regional Park near Cisco. That’s just on the other side of Monticello and not that far of a drive.
For: August 22-28
Mars resumed its west to east motion against the background stars back in early July. Tuesday evening, Mars will finally pass between Saturn and the bright red star Antares. Look south and compare the reddish color of Mars to the red of Antares. Can you see how someone might confuse the star for Mars? Watch over several evenings and you can actually see a planet orbiting the Sun. Join me Friday night as we will observe the sky from Urbana’s Sweetcorn Festival. We will be near the One Community Together stage. Saturday evening Venus and Jupiter pass within a half degree of each other but you have to locate a low horizon to catch them.
For: August 29-September 4
If you hear about a solar eclipse on Thursday, yes, it is happening but we can’t see it from Illinois. Ideally you’d have to be in Central Africa to see it. This is an “annular eclipse” like we had here in May, 1994, where the Moon is a little farther away from the Earth and thus doesn’t completely cover the Sun. So it looks like a ring in the sky. For this event, the Sun won’t be above the horizon when the Moon passes in front of it. In fact, the eclipse starts after 2am our time. The Astronomical Society of South Africa is planning on live streaming the event at https://www.youtube.com/watch?v=xebDaX1PJF0. If you’re up, check it out!
See Dave Leake's "Prairie Skies" column in the Champaign-Urbana News-Gazette each Monday morning.