Megaripples-moving-across-Mars-surface-2020
Megaripples on Mars (Image Courtesy : NASA)

There is no limit to people's curiosity about space, and it is still growing day by day. Thus, provoking human curiosity, scientists discovered that the “Megaripples” are moving across the surface of the Red Planet, and this way, the research accordingly dispels the belief that these megaripples have not moved since their origination. Megaripples basically refers to the colossal wave of sand, and on the Mars, these are migrating across the planet’s surface at a slow pace.

ADVERTISEMENT

We all are almost acquainted with the sand waves that is found on the desert areas of our home planet. But, this gigantic sand waves are not also quite surprising for that of the Mars. Rather this enormous aeolian megaripples are thought to be developed on the Martian surface millions of years ago, and the waves might indicate that the wind shear on Mars is much more powerful than previously thought by the astronomers.

Simone Silvestro, and other researchers carried out a study, entitled their paper as "Megaripple Migration on Mars". It was published in the 'Journal of Geophysical Research: Planets' on 27 June 2020.

The newly conducted study oppose to the conventional model of atmospheric science that proposes that the Martian wind flow is not so strong enough to diverge the enormous extent of sand field on Mars to create sand waves. That circuitously indicate the thin Martian atmosphere which is able generate such strong wind flow.

Findings of the research

Basically the wind flow accumulates sandy landforms or bedforms and forms the ripples, dunes, etc. Being similar to that in the deserts on the Earth, these are also found on Mars. On the Earth, the ripples generally forms at almost every 10 centimetres. But the 'megaripples' are little different than the 'ripples'. Megaripples are the large version of ripples that undulates every 30 centimetres to tens of metres.

ADVERTISEMENT

Megaripples consists of greater than 1 millimetre coarse sand grains, and so only strong wind flow can displace them. But Martian atmosphere is predicted to be faint, so that, according to the current atmospheric models, such strong wind having the ability to displace this coarse sand grain is not likely to blow across the Martian surface. Thusly, the megaripples on the Red Planet are being speculating to be "static relics of a past climate", when the Martian atmosphere is thought to be much denser.

But the astonishing fact is that some bright megaripples on Mars are active in recent days as those creep along though at a slow pace of approximately 10 centimetres per Earth year, which are quite similar to the ripples that of the Lut Desert of Iran. And these presently active megaripples of Mars do not require previously assumed atmospheric state.

Scientists have used the imagery datasets from NASA's Mars Reconnaissance Orbiter, which allows the researchers to have a much closer view of two sites near the equator of Mars, these are McLaughlin crater and Nili Fossae region. They have discovered nearly a total of 1,400 megaripples, of which 1,100 in McLaughlin crater, and almost 300 megaripples in the Nili Fossae region of Mars. The researchers analysed the time-lapse video of the both site for respectively 7.6 and 9.4 years apart, in order to find out if there were any movement of the megaripples.

ADVERTISEMENT

On the Earth, the process of the movement of ripples is called "impact-driven creep", which depicts, the wind on Mars drives the small sand grains, and thus once these grains are set in motion, they start knocking into the larger grains and drag them into motion.

As the research team suggests, the sand dunes on Mars probably donate their sand grains in the migration of the megaripples, as it is found that the dunes also migrated in the same direction as of the megaripples. So, this recent discovery surely insist the conventional atmospheric models to be revised, which suggests that the wind in the Red Planet is not potent enough to mobilize the megaripples.

The lead author of the study wishes to extend his research of moving wave of sand to allover the Mars. He speculates that the fastest migrating megaripples might be located near the rapidly moving sand dunes. Thenceforth, the researchers apprehend that the atmospheric condition and the moving megaripples might lead to the dust-storm in the Red Planet, and that is the bad news for probable future human habitats and Mars rovers likewise, as inclement atmospheric condition could mess up the solar panels and feasible human habitat.


Read also

Post a Comment

Please do not enter any spam link in the comment box

Previous Post Next Post