MRO MARCI Weather Report for the week of
27 July 2009 – 2 August 2009

Martian weather between 27 July 2009 and 2 August 2009:

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

The large dust storm that previously found its way into eastern Noachis and Hellas continued this past week. The storm halted in Noachis but continued to extend dust over Noachis, Hellas, Promethei, and part of Cimmeria throughout the week. By week's end the storm had begun to taper off and leave more of a diffuse dust cloud over the southeastern mid-latitudes. Increased dust activity was also observed in the northern mid-latitudes (especially over Arcadia, Deuteronilus, and Tempe) throughout the week. A cross-equatorial storm advanced south from Acidalia on the 30th, moving down into Chryse and Xanthe, and even making eastern Valles Marineris a bit hazy after a couple of days. Water-ice clouds persisted across the northern mid-latitudes and over Arsia Mons throughout the week. Despite the recent increase in weather activity on Mars, the Spirit (MER-A) and Opportunity (MER-B) rovers continued to see fairly clear skies.

This week’s MARCI “movie” can be downloaded HERE (9.1 MB .mov file).

Earlier Mars Weather Reports are available HERE.

About the Quicktime Movie:
The movie (a .mov 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 two Mars Exploration Rovers, Opportunity (on Meridiani Planum) and Spirit (in Gusev Crater). 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 Quicktime movie.

Malin Space Science Systems, Inc., San Diego, California, U.S.A.