Summer is a great time to get outside and enjoy bright constellations, but be warned: many don’t look anything like what they are named after. Still, it’s really not hard to find simple patterns in the stars. Make up your own names if that helps you find your way around the sky.
In the east, look for the three stars of the Summer Triangle. Each star of is part of a separate constellation.
Vega is the brightest of the three stars, but its constellation of Lyra the harp barely resembles a stringed musical instrument. Altair marks the eye of Aquila the eagle, which looks more like a stingray in the sky. Deneb marks the tail of Cygnus the swan. Here’s one constellation that at least looks a little like what it’s named after, although many people simplify this star pattern and refer to it as the Northern Cross.
Low above the southern horizon scoots Scorpius the scorpion. It’s hard not to imagine a curly-tailed stinging creature here, though it’s also been called a fishhook, or simply a letter J.
The heart of the scorpion is marked by the red giant star Antares. Because of its brightness and red color, “Anti-Ares” can easily be confused with the red planet Mars.
Just east of the scorpion is one of the best examples of a constellation that looks nothing like you expect. According to ancient mythology, Sagittarius the archer was not just a person with a bow and arrow. He was a centaur -- half man, half horse. It takes a lot of imagination to see a centaur in this pattern of stars. To most modern eyes, Sagittarius looks more like a teapot.
Planets on the Move
While not as bright as it was last month, Mars is moving quickly against the background stars. Mars starts the month just west of the blue-white star Spica, in Virgo the maiden. Note the planet’s position relative to Spica each night and watch Mars slide eastward toward an August rendezvous with Saturn. On the evening of July 5 Mars is joined by the First Quarter Moon. If you have binoculars, take a look at this nice pairing. From July 12 to 14, Mars appears right next to Spica.
Further east, Saturn sits within Libra the scales, appearing as a bright, pale, yellow dot roughly halfway between Spica and Antares. The Moon will pass near Saturn on the evening of July 7. Saturn moves very slowly in the sky as seen from Earth. Mars will catch up to Saturn by the end of August but will be even fainter than it is now.
Look through a telescope at these two planets to reveal more differences: Saturn shows off its magnificent rings, while Mars looks like a small, pale pink fuzzy dot. Mars may be closer to us than Saturn, but it’s also a whole lot smaller.
To see more planets, you’ll have to wake up early. Venus shines brightly in the predawn glow just above the east-northeastern horizon. A thin crescent Moon will join Venus on the morning of July 24, but you'll need a clear horizon to see them.
In recent months, Mercury made a nice apparition in our evening skies, setting just after sunset. But now, the speedy little planet closest to the Sun has whipped around in its orbit to appear on the opposite side of the Sun, rising before sunrise. Early-rising, keen observers with a clear eastern view might be able to spot Mercury about 7 degrees east of Venus between July 12 and 20.
Happy Birthday to Cassini
When you look towards Saturn on the next clear night, take a moment to consider the Cassini mission, which on June 30 celebrated the tenth anniversary of its arrival at the ringed planet. For ten years, the school bus-sized spacecraft has been sending back stunning photos of Saturn, its rings, and many moons. Join the celebration and learn more about Cassini and the fascinating planetary family it studies by visiting saturn.jpl.nasa.gov.
Summer Star Parties
The next two free public star parties are scheduled for Friday, July 25, at Bowie Park in Fairview and August 15 at Bells Bend Outdoor Center. Both events are from 8:30 to 10:30 pm.
Members of the Barnard-Seyfert Astronomical Society will set up their telescopes so everyone who attends can observe Saturn, the Hercules star cluster, and more. It’s great fun for all ages.
Star parties are weather dependent and may be cancelled. Visit our star parties page for updates before making the trip, especially if the weather is iffy. You'll also find star party tips, driving directions, and a calendar of future events.
Two great shows are now showing in the Sudekum Planetarium through August 31:
Dynamic Earth: Follow energy from the Sun as it flows into Earth’s atmosphere, oceans, and biosphere. Explore Earth's climate system using supercomputer simulations and models based on satellite data. Ride along swirling ocean and wind currents, dive into the heart of a monster hurricane, come face-to-face with sharks and gigantic whales, and fly into roiling volcanoes to discover our dynamic Earth. This show is presented thanks to the generous support of the Sudekum Memorial Trust.
Back to the Moon For Good: To win the $30 million Google Lunar XPrize, a team must land a robotic spacecraft on the Moon, navigate 500 meters across the lunar surface, and send video, images, and data back to Earth. This dramatic program examines what missions in the 1960s and 1970s taught us about Earth’s nearest neighbor in space, introduces us to some of the teams competing for the largest prize in history, and presents one possible scenario for our future on the Moon.
Check our web site for details and show times. Be sure to check out our live show Skies Over Nashville or Saturday night laser shows featuring dramatic visual effects and a great variety of music presented through the end of August!