Curiosity Detects Ripples in Mars Similar to Earth's Underwater Bedform
A new study on Mars revealed that the red planet are harboring some kind of a dune-like structures that can't be seen on any dry land on Earth, but resembles the kind of ripples that were formed by currents underwater the Earth.
The study, published in the journal Science, suggests that the bedforms, which are small ripples or large dunes caused by winds blowing over sand, found in Mars are spatially uniform in size and typically have asymmetric profiles with angle-of-repose lee slopes and sinuous crest lines, making them unlike terrestrial ripples.
Terrestrial bedfroms on Earth can be small ripples ranging from few inches to foot long or large dunes that can stretch for miles. However, the bedforms detected on Mars are somewhere in between the size of small ripples and large dunes.
For the study, researchers analyzed high resolution images from the Mars Science Laboratory Curiosity rover and the Mars Reconnaissance Orbiter. Researchers then noted that the bedforms in Mars do not look like anything that was made by the wind. It is more similar to a fluid-drag ripples that can be found on Earth's underwater.
According to a report from Space.com, Mars is too cold and dry for liquid water to persist long on its surface. This led the researchers to hypothesize that the ripples were made not by liquid but by winds of the Martian atmosphere. Researchers believe that the bedforms found in Mars were formed by the higher kinematic viscosity of air greatly affecting the sand on the low-density atmosphere of the red planet.
To test out their theory, researchers created a model, which suggested that wind-drag ripples get smaller as the atmosphere of Mars thickens. In order to find evidences of wind-drag ripples on Mars, the researchers analyzed the data collected by NASA's Opportunity rover at the 3.7 billion years old Burns formation.
The researchers discovered signs of wind-drag ripple in the ancient rock. The discovery of wind-drag ripples on ancient rocks may open a new path for researchers trying to understand how Mars lost its atmosphere and become drier over time.