Stellar Vista Observatory Sky Report
John Mosley
July 19 – 25
The Sky Report is presented as a public service by the Stellar Vista Observatory, a nonprofit organization based in Kanab, Utah, which provides opportunities for people to observe, appreciate, and comprehend our starry night sky. Additional information is at www.stellarvistaobservatory.org. Send questions and comments to [email protected].
I focus on things in the sky that change, which is mostly the planets because they move continuously, so let’s start with Venus.
Venus is by far the brightest planet (it’s closer to earth than the others and is highly reflective) and you don’t have to wait until late for it to rise. Venus appears in the west as the sky grows dark, early in evening twilight well before any stars appear. Venus sets 1-3/4 hours after the sun, but you can see it at the moment of sunset if you know where to look.
A few degrees to the lower right of Venus is the much fainter planet Mars. You’ll want binoculars to see Mars. Venus passed Mars on July 12, and Venus’ orbital motion around the sun is carrying it away from Mars so their separation increases noticeably night to night.
Mars sets four minutes earlier each night and we’ll lose it by the end of the month when it sets too early to see, but it reappears in the morning sky early next year.
The bright star next to Venus is Regulus, the brightest star in Leo the Lion. Regulus is almost twice as bright as Mars. They’re at their closest on Tuesday when they’re separated by 1½ degrees. Again, use binoculars, and watch Venus approach and then pass Regulus, just as it approached and passed Mars.
Saturn rises by 10 and Jupiter by 11 and at midnight they’re both easily visible low in the southeast. Jupiter is second only to Venus in brightness while Saturn, 20 degrees to the right of Jupiter, is 1/10th as bright as Jupiter, although that is still brighter than any star. Any astronomical telescope will show Saturn’s famous rings and its largest moon Titan and Jupiter’s four largest moons plus some cloud bands.
The moon is nearly equidistant from Jupiter and Saturn on Saturday night. It’s near Saturn the night before and Jupiter the night after.
Turning to stars, the seven bright stars of the Big Dipper are half-way up the western sky when the sky becomes fully dark. Contrary to popular belief, the Big Dipper is not a constellation; it is the most conspicuous part of Ursa Major, the Great Bear, most of which is below the Dipper. To the right there’s a Little Bear, and a Little Dipper, and the North Star marks the end of its handle.