Western Slope Skies - Mars in October

Oct 2, 2020

Mars, as imaged by Viking 1 Orbiter

As evening twilight deepens, look to the east. You’ll see a brilliant red star rising. That star is actually not a star, but the planet Mars. Over the next several weeks, we on Earth will be swinging by Mars on our faster orbit about the Sun, allowing for great views of our planetary neighbor.

About every 2 years and 2 months, Mars and Earth line up relatively near each other on the same side of the Sun. This alignment is called “opposition,” indicating that Mars appears in our sky in a direction opposite the Sun. But not all Mars oppositions are created equally. Due to Mars’ highly elliptical orbit, its distance at opposition can range from 34 million to 64 million miles. The opposition on October 13, 2020 is a special one. Mars will be only 39 million miles distant during much of October, closer to us than at any time from now until year 2035. Because Mars is relatively nearby this month, it appears very bright, a tad brighter than even Jupiter, the largest planet. This will be a great time to view Mars through telescopes, to spot dark surface markings called albedo features, the south polar cap, and occasionally, clouds in the Martian atmosphere. Telescopic views of Mars from the Western Slope may be better this month than during Mars’ closer opposition in 2018, because Mars will rise higher in our sky. Let’s just hope that there won’t be a repeat of Mars’ 2018 Global dust storm! That storm mostly obscured Mars’ surface from view and ended the life of NASA’s Opportunity Rover.

Mars has captured the attention of the global scientific community. Three robotic spacecraft are currently speeding toward Mars, about to join the 6 orbiters, 1 rover, and 1 lander now studying the Red Planet. The United Arab Emirates’ Hope Orbiter will study Mars’ atmosphere. NASA’s Perseverance Rover will seek evidence for past Martian life and cache samples for future return to Earth. And, China’s Tianwen-1 orbiter, lander, and rover will conduct a multitude of scientific studies.

So take some time this October to enjoy Mars at its best and brightest. Western Slope Skies is produced by the Black Canyon Astronomical Society. This episode was written and recorded by Art Trevena.

Web links for Mars