Monday May 30th the planet Mars will be at its closest to the Earth for this opposition at a distance of 0.50321 AU (75,279,144 km; 46,776,292 miles). Mars has an orbital shape that is more elliptical then the Earth’s orbital shape and like the Earth Mars has a perihelion and aphelion distance each orbit. Combine this with its roughly twice the Earth’s orbital period around the Sun and there is an interesting dynamic that happens about every 26 months when Mars reaches opposition. If Mars is at its respective perihelion, closest to the Sun, and is also near its opposition, and the Earth is near its aphelion, furthest from the Sun, then Mars will appear at a different apparent size relative to other oppositions.
Mars is unmistakably bright during its opposition and perihelion. At an apparent magnitude of nearly -2.0 Mars outshines nearby Saturn (0.0), and its stellar doppelganger the reddish star Antares (1.0).
Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.