Written by Alex Innanen, Atmospheric Scientist at York University
Earth planning date: Friday, Oct. 9, 2026
Happy New Mars Year! The Martian new year begins with the arrival of northern spring, or the vernal equinox. Seasons on Mars are tracked by degrees of solar longitude, with each season spanning 90 degrees as the planet completes its 360-degree orbit. Mars Year 39 began at a solar longitude of Ls = 0° at the end of September on Earth. With the new year now underway, Gale Crater, located just south of the equator, has entered autumn.
As Michelle described last week, we marked the Martian new year by beginning our drill campaign at “Basque Lakes.” This week’s work focused on completing the drilling before the rover’s weekend departure. After reviewing the results of the previous week’s laboratory activities, the SAM team selected an additional GCMS (Gas Chromatograph/Mass Spectrometry) experiment. Although GCMS requires considerable energy, Monday’s plan provided four full sols, leaving room for a range of remote-sensing observations with Mastcam and ChemCam, as well as contact science on the drill tailings—the fragments of rock and mineral material left behind after sampling. This weekend’s plan includes two additional sols to finish drilling at Basque Lakes and collect any final contact- or remote-science targets before beginning the journey back toward the distinctive crystal formations observed in the “Chiu Chiu” region.
While these activities continue, the atmosphere around us is undergoing its own seasonal transition. Autumn has brought back the high-altitude twilight clouds, which are illuminated by the low Sun at sunset. Although twilight-cloud activity is expected to increase as autumn progresses, Wednesday afternoon cloud recordings already captured the season’s first high-altitude clouds. Most clouds seen at Gale Crater are suboptical, meaning they are too thin to be detected by either human eyes or Curiosity’s robotic cameras, but twilight clouds are bright enough to appear in raw Navcam images. I look forward to another Martian autumn spent watching the clouds pass.
