The Summer Evening Sky is Getting Crowed!
Rest up in the afternoon so you can be nice and fresh to take in some divine summer stargazing this month. It’s not truly dark enough until after 10:30 pm, but it’s wonderful when it does finally get dark.
It’s planets a plenty in the evening sky this month. From the later stages of evening twilight to midnight you’ll be able to see all five of the planets visible to the naked eye. Two of them are also having close encounters with Earth this month.
Venus is the brightest of the planets by far, and the brightest star-like object in the night sky. Before evening twilight it pops out in the low western sky as bright as can be. Right now it’s about 96 million miles from Earth, and over the course of the month it will draw about 20 million miles closer to the Earth as it continues to orbit around the sun. Venus is so bright not only because it’s so close to Earth this month, but because the heavy cloak of cloud cover really reflects a lot of sunlight. The clouds make Venus a less than attractive target for your telescope, but what is cool is that Venus goes through phases just like our moon does. That’s because its orbit lies within Earth’s orbit in our solar system, and the angle between the sun, Earth, and Venus is always changing. Currently Venus resembles an oval-shaped gibbous moon, and later on this month it will shrink to a crescent shape
While you’re gazing at Venus in early in July, see if you can spot Mercury a little to the lower right of Venus and closer to the horizon. It won’t be nearly as bright though. Like Venus, Mercury will be more or less a half moon shape through a telescope. It also goes through phases. On July 14th the new crescent moon will be parked just above Mercury, and the 15th the moon will have a spectacular celestial hugging with Venus. Don’t miss that.
Meanwhile, the second brightest “star” in the evening sky is Jupiter, popping out of evening twilight fairly high above the southern horizon. Through even a small telescope you can easily see up to four of Jupiter's largest moons and maybe some of Jupiter's brighter cloud bands.
In the low southeastern sky all this month, the planet Saturn is on the rise in the vicinity of the constellations Scorpius and Sagittarius. Saturn reached its closest approach to Earth last week, and it’s wonderful to look at the planet and its ring system through a telescope.
If you’re a really a night owl, look for Mars rising in the low east-southeast sky toward midnight. It’s really bright and really red, and late this month it will reach its closest approach to Earth in fifteen years. It’s the biggest story in the night sky in 2018 as far as I’m concerned. If you’ve ever needed an excuse to purchase a telescope now’s the time to do it. Mars will put on quite a show through most of September. Stay tuned for much more on Mars!
The brightest actual star in the sky this month is Arcturus, the brightest star of the summer sky. At twilight’s end Arcturus is perched high in the western sky at the tail of a giant kite. That kite is more formally known as the constellation Bootes, the hunting farmer. How the kite is supposed to be a hunting farmer is anyone’s guess. Arcturus is a giant star, more than 22 million miles in diameter and more than 36 light-years distant, with one light-year equivalent to about 6 trillion miles.
n the eastern heavens, you’ll see the prime stars of summer on the rise. As we move through July they will be a little higher at the start of each night as the Earth passes in their direction while orbiting the sun. The best way to find your way around the summer stars is to locate the “Summer Triangle” made up of three bright stars, the brightest in each of their respective constellations. You can’t miss them. They’re the brightest stars in the east right now.
The highest and brightest star is Vega, the bright star in a small faint constellation called Lyra the Harp. The second brightest star on the lower right is Altair, the brightest in Aquila the Eagle. Altair is on the corner of a diamond that outlines the wingspan of the great bird. The third brightest at the left corner of the summer triangle is Deneb, a star possibly at least 1500 light-years away. It’s also the brightest star in the tail of Cygnus the Swan. Cygnus is known as the “Northern Cross” because that’s what it really looks like. Deneb is at the head of the Northern Cross, presently laying on its side as it rises in the east.
In the northern sky look for the Big Dipper hanging from its handle in the northwest, along with the fainter Little Dipper standing on its handle. The moderately bright star Polaris, otherwise known as the North Star, is at the end of the Little Dipper’s handle. Every single thing in the sky, including the sun and the moon, appear to revolve around Polaris every 24 hours.
Enjoy the short but starry planet-filled nights of July 2018!
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul, and is author of the book, “Stars, a Month by Month Tour of the Constellations” published by Adventure Publications. Available at bookstores and online at www.adventurepublications.net.
If you have any astronomical questions or want me to write about something you’re seeing in the night sky drop me a line at firstname.lastname@example.org