BY MIKE LYNCH
The stars and constellations of summer are back in the evening sky, along with some bright planets. Try to get an afternoon nap in because summer stargazing is a very late night affair!
Even before the end of evening twilight, the very bright planet Venus pops out in the low west-northwestern Pottsville sky. Mars also occupies the low northwestern early evening sky, although not nearly as bright as Venus. The red planet is completing its long goodbye after putting on a great show last fall. Early in July, it’s still barely visible in the very low western sky, but by mid-month it’ll be lost in the glow of the setting sun. Before it leaves, however, it’ll give us one more great show with the much brighter Venus. On Thursday, Mars will be just to the upper left of Venus in the western twilight, but by the 12th and 13th, Mars and Venus will be in a much tighter celestial hug, less than half a degree apart!
The brightest actual star in the sky this month is Arcturus, starting out the evenings perched high in the western sky. Arcturus also serves as the brightest star in the constellation Bootes the Herdsman. Bootes looks much more like a giant though, with Arcturus at the tail of the kite. Arcturus is a red giant star more than 22 million miles in diameter. Our sun isn’t even a million miles in diameter! Arcturus is nearly 37 light-years away from Earth, with one light-year equally nearly 6 trillion miles!
In the eastern heavens, you’ll see more of the great stars and constellations of summer on the rise. The best way to find your way around them is to use the Summer Triangle, an asterism made up of three bright stars, the brightest in each of their respective constellations. You can’t miss them. Just look for the three brightest stars in the eastern sky and that’s it.
The highest and brightest star is Vega, the brightest star in the small, faint constellation Lyra the Harp. The second brightest star is Altair, the brightest luminary in Aquila the Eagle. The third-brightest Summer Triangle star is Deneb, marking the tail of Cygnus the Swan. Deneb is a gargantuan star at least 1,400 light-years away and probably much more distant. Within the constellation Cygnus is the “Northern Cross,” rising sideways in the eastern heavens with Deneb at the head of the cross.
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 celestial object in the sky, including the sun and the moon, appear to revolve around Polaris every 24 hours. Of course, we’re just seeing a reflection in the sky of Earth’s rotation.
In the low southern sky, the classic summer constellation Scorpius the Scorpion is on patrol. It truly resembles a scorpion. Antares, the bright reddish star, marks the heart of the beast. To Antares’ upper right are three moderately bright stars in a near-perfect row that outline the scorpion’s head. To the lower left of Antares, there’s a curved line of stars outlining the tail and the stinger. Just to the left of Scorpius is a formation of stars that clearly resembles a teapot. Those are the brightest stars in the constellation Sagittarius the Archer, a centaur shooting an arrow at Scorpius.
The bright planets Saturn and Jupiter are making their first appearance in the evening sky since January. Early in July, about an hour after evening twilight, look for Saturn rising in the low southeastern sky. Closely following behind to the lower left is much brighter Jupiter. Both planets are nearing their closest approaches to Earth in 2021.
Both Saturn and Jupiter are great to look at through even a small telescope, although it’s best if you stay up as late as possible to view them. This allows them time to rise above the blurring effects of Earth’s atmosphere near the horizon. Saturn is wonderful to gaze at, with its ring system more than 150,000 miles in diameter.
Mike Lynch, an amateur astronomer and professional broadcast meteorologist, can be reached at mikelynch@comcast.net.
