In the Matt Damon movie "The Martian," the winds on Mars are portrayed as being savage, relentless hurricanes that would give any terrestrial storm a run for its destructive money. However, the realities of the Red Planet's windy nature is a lot more subtle, slowly shaping the aeonian landscape over long periods of time.
But there are many mysteries, principally based around how surface winds influence small-scale structures and how a human presence on the surface may modify those winds.
ANALYSIS: The Martian Winds WON'T Blow You Away
Though previous Mars missions have been able to image the planet's vast dune fields, watching them slowly evolve while being molded by prevailing winds, it wasn't until NASA's Mars Reconnaissance Orbiter (MRO) arrived in 2006 that we could gain super high-resolution observations of ripples on the individual dunes. Having such a fine resolution view meant planetary scientists could capture long-duration snapshots of individual dunes, and even features on those dunes, changing over time, thereby piecing together Mars' windy nature.
"I have always wondered which way the winds blow on Mars," said Mary Bourke, of the School of Natural Sciences in Trinity College Dublin. "Of course we don't have long-term meteorological stations up there to help me answer that question, so we have previously had to use the shape of sand dunes or the elongation direction of sand streaks to map wind flow, but we miss much of the finer detail there."
PHOTOS: Mind-Blowing Beauty of Mars' Dunes
Understanding Martian winds is not only an academic curiosity about the formation of sand dunes on another world. As NASA cranks up its Mars exploration efforts, we need to know as much as possible about the Martian atmosphere, and this means gaining a better grasp on how short term and long term trends in weather patterns may impact robotic and future human missions to the Red Planet's surface.
Using data from the High-Resolution Imaging Science Experiment (HiRISE) camera on board the MRO, and comparing the Martian features with features on sand dunes found on Northern Ireland's peninsula of Magilligan, Bourke's team was able to create a 3-D model of Mars surface winds. From this model, the researchers were able to, for the first time, see how large dunes on Mars modify localized wind flow. It's all very well understanding which direction the prevailing winds are blowing, but this research provides valuable information about how a dune-filled landscape on Mars may channel or even redirect winds on the smallest of scales.
In other words, we're looking at the kinds of scales that would impact rovers or even astronauts on the dusty surface. Also, we're looking at the kinds of scales that could be influenced by the presence of a permanent human presence on Mars - if you erect a structure on this wind-driven world or if a landing spacecraft disrupts the dunes, how will the Mars winds be modified?
NEWS: Bouncing Sands of Mars Blow in the Wind
"We worked with data from the Proctor Crater region on the southern highlands of Mars, and found that ripples on the dunes moved around 1.5 meters per year," said Bourke. "This is a much more accurate insight than the one we had before - we now have a better platform from which to consider how Martian landforms have evolved, and how they will evolve when structures such as spacecraft disturb them in the future."
This fascinating study has been published in the journal Nature Geoscience.
Source: Trinity College Dublin