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MRO MARCI Weather Report for the week of
20 December 2021 – 26 December 2021

Captioned Image Release No. MSSS-602 — 29 December 2021

NASA/JPL-Caltech/Malin Space Science Systems

Martian weather between 20 December 2021 and 26 December 2021:

The MARCI acquires a global view of the red planet and its weather patterns every day. Please click and play the movie (.mp4 file) to see how the weather on Mars changed during this time.

Regional dust storm activity picked up this past week. The week began with storms developing in Solis-Sinai and north of Argyre, which developed into regional storms that propagated northeast and north into Valles Marineris. Storm activity in Hellas Basin and surrounding regions initiated the annual transition of Hellas’ local atmosphere from cloudy to dusty. By mid-week, local storm activity that developed along the seasonal south polar cap edge in Promethei Terra propagated northward over the plains of Hesperia. During the next couple of sols, that storm propagated eastward along the seasonal south polar cap edge into Cimmeria Terra and as far north as Gale Crater (location of the Curiosity Rover). At polar latitudes in both hemispheres, additional local storms developed along the cap edges. By the end of the week, warmer atmospheric conditions at equatorial latitudes signaled the abating of the aphelion cloud belt. The Perseverance Rover in Jezero Crater and the InSight lander on Elysium Planitia had storm-free afternoon skies all week.

This week’s MARCI “movie” can be downloaded HERE (8.9 MB .mp4 file).

This week’s MARCI “movie” can be downloaded HERE (8.9 MB .mov file).

Earlier Mars Weather Reports are available HERE.

About the Movie:
The movie (a .mp4 file that you can click and play, above) was generated from images obtained by the Mars Color Imager (MARCI) onboard the Mars Reconnaissance Orbiter (MRO). During a nominal operational week, a total of about 273 MARCI images, taken in three of the camera’s seven color filter bands (420, 550, and 600 nanometer wavelengths), are map projected and mosaiced together to produce seven false-color daily global maps. These maps are then projected onto a sphere with north at the top and east to the right and with the mid-afternoon vantage point of an observer in the orbital plane (the imaginary plane that the planet draws out as it circles the Sun). Black areas in the movie are the result of data drops or high angle roll maneuvers by the spacecraft that limit the camera’s view of the planet. Equally-spaced blurry areas that run from south-to-north (bottom-to-top) result from the high off-nadir viewing geometry, a product of the spacecraft’s low-orbit, 250 km x 316 km (155 miles x 196 miles). The movie is rendered at a lower resolution than the intrinsic 1–2 km nadir resolution that the MARCI provides, so that it is practical to view and share via the Internet. The small white circles on these images of Mars indicate the locations of the Mars 2020 rover, Perseverance (in Jezero Crater) and the Mars Science Laboratory rover, Curiosity (in Gale Crater) and the InSight lander (in Elysium Planitia). Other locations on Mars referenced in the weather report can be found by referring to the map below. Note that the still image of Mars depicted at the top of this page is a single frame from the movie.

Reference Map — Martian Place Names Commonly Mentioned in Mars Weather Reports simple cylindrical map of Mars with various place names indicated
NASA/JPL-Caltech/Malin Space Science Systems

Citation and Credit
The image(s) and caption are value-added products. MSSS personnel processed the images and wrote the caption information. While the image(s) are in the Public Domain, NASA/JPL-Caltech/MSSS requests that you credit the source of the image(s). Re-use of the caption text without credit is plagiarism. Please give the proper credit for use of the image(s) and/or caption.

Image Credit:
NASA/JPL-Caltech/Malin Space Science Systems

To cite the image(s) and caption information in a paper or report:
Malin, M. C., B. A. Cantor (2021), MRO MARCI Weather Report for the week of 20 December 2021 – 26 December 2021, Malin Space Science Systems Captioned Image Release, MSSS-602,

Malin Space Science Systems (MSSS) built and operates the Mars Science Laboratory (MSL) Curiosity rover Mast Camera (Mastcam) and Mars Hand Lens Imager (MAHLI) and Mars Descent Imager (MARDI), the Mars Reconnaissance Orbiter (MRO) Mars Color Imager (MARCI) and Context Camera (CTX), and the Jupiter Orbiter (JUNO) camera (Junocam). MSSS also built and operated the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC). In addition, MSSS built the Mars Odyssey (ODY) Thermal Emission Imaging Spectrometer (THEMIS) Visible (VIS) camera subsystem, which shares optics with the thermal infrared instrument and is operated at Arizona State University (ASU). MSSS also built the Mars Descent Imager (MARDI) for the Phoenix Mars Scout lander, the suite of high resolution cameras aboard the 2009 Lunar Reconnaissance Orbiter (LRO), and Origins-Spectral Interpretation-Resource Identification-Security-Regolith Explorer (OSIRIS-REX) mission. MSSS is currently working on cameras for the Mars 2020 Rover mission.