Back-to-school planetary chums Mars and Saturn hang out in the cosmic playground of the early evening’s southwestern sky.

Find Mars, Saturn and a young crescent moon together Sunday night after sunset in the western heavens. Look carefully, and you may discern the rusty red color of Mars. Our neighboring crimson planet hangs to the lower left of the large, ringed Saturn. Both planets are zero magnitude objects and can be seen with the unaided eye. On Monday night, the moon gets chunkier and moves away from the planetary duo.

A week from now, Mars remains to Saturn’s left, above the western horizon, and they set eight minutes apart. By month’s end, the ringed planet sets after 9 p.m., while the red one sets around 10 p.m.

In July, Jupiter hid behind the sun’s glare. It now rises in the east at about 4 a.m. Morning joggers and dog walkers can spy the negative 1.8 magnitude planet well-placed above the horizon (in the constellation Cancer) about 5:30 a.m.

By the middle of September, the large gaseous planet Jupiter rises around 3:30 a.m., and by the end of the month, it ascends our heavens starting about 2:45 a.m.

Just before sunrise, you may catch Venus low on the eastern horizon. A beach with an eastern view would be perfect. The effervescent planet gets caught in the sun’s glare later in September and climbs out of view.

For those looking forward to the splendor of colorful leaves, the autumnal equinox — marking the official start of fall — occurs Sept. 22 at 10:29 p.m. Eastern Daylight Time (Sept. 23 at 2:29 a.m., Universal Time), according to the U.S. Naval Observatory. From our perspective, the sun appears to cross the Northern Hemisphere into the Southern Hemisphere. But we earthlings, and our blue planet are moving. The sun is stationary.

Down-to-Earth events

Sept. 2: “Seeing Planets Around Other Suns: First Light with the Gemini Planet Imager,” a talk by astronomer Marshall Perrin, at the Space Telescope Science Institute (STScI), on the Johns Hopkins University campus, 3700 San Martin Dr., Baltimore. STScI Auditorium. 8 p.m.

Sept. 5: “Death by Black Hole,” a talk by astronomer Cole Miller, at the University of Maryland Observatory, College Park. 9 p.m. Weather permitting, telescope observing afterward.

Sept. 8: “Stars Tonight,” at the David M. Brown Planetarium, 1426 N. Quincy St., Arlington. 7:30 p.m. $3.

Sept. 13: “Impactors from the Sky,” a talk by Melissa Hayes-Gehrke, University of Maryland senior lecturer, at the National Capital Astronomers’ regular meeting. She will discuss asteroid threats and the Chelyabinsk meteor airburst from February 2013. At the University of Maryland Observatory, College Park. 7:30 p.m. capital

Sept. 19: “The Search for Life in the Solar System and Beyond: Habitats and Exotic Possibilities,” a lecture by Dirk Schulze-Makuch of Washington State University. Hosted by the Philosophical Society of Washington at the John Wesley Powell Auditorium, adjacent to the Cosmos Club, 2170 Florida Ave. NW. 8 p.m.

Sept. 20: With a chill in the air and beautiful urban heavens, the National Park Service and the National Capital Astronomers host “Exploring the Sky.” At Rock Creek Park, near the Nature Center in the field south of Military and Glover roads NW. 8 p.m.

Sept. 20: Learn all about Mayan calendars at the Montgomery College planetarium, Takoma Park, 7 p.m.

Sept. 20: “Comet Siding Spring’s Close Approach to Mars,” a talk by Tony Farnham, University of Maryland senior research scientist. Find out how this comet will have a close encounter with our neighboring red planet Mars on Oct. 19. The talk will be at the University of Maryland Observatory, College Park. Through telescopes, view the sky afterward. 9 p.m.

Sept. 27: The 31st annual NOVAC Star Gaze. In the afternoon, talk to astronomers, and after sunset, check out the stars and planets. At C.M. Crockett Park, Midland, Va. 3-11 p.m. $6 parking fee for non-Fauquier County residents’ cars.

Sept. 27: Sneak far from city lights and gather in the glorious early fall heavens, guided by Sean O’Brien of the National Air and Space Museum. At Sky Meadows State Park near Paris, Va. Parking $5. Arrive before dark. 6:30-9:30 p.m. Park phone: 540-592-3556.

Blaine Friedlander can be reached at