Underwater dunes here on Earth could help unlock the secrets of the dunes seen on our planetary neighbour
In the 1970’s missions to Venus revealed that there is a fine-grained material similar to sand on the planet’s surface. Then during the 1990’s the Magellan mission found evidence of wind erosion in the form of numerous sand dunes and wind streaks. Despite its proximity to Earth the blistering surface temperatures and soaring pressures seen on Venus’s surface mean the atmospheres of Venus and Earth truly are worlds apart. Due to this stark contrast in climates, it’s not possible to use the sand dunes here on earth, that form under low atmospheric pressures, to explain the sand structures seen on Venus. It would be naive to believe that the processes that made the dunes could be comparable, therefore, astronomer Lynn Neakrase at New Mexico State University and his team have been looking elsewhere.
Neakrase and the team have focused on underwater dunes as they believe these bare similarities to those found on Venus and could, therefore, be used to understand them. Underwater dunes form under high pressures due to the vast volumes of dense water surrounding them this simulates the high atmospheric pressures on Venus. In addition, the thick atmosphere is mimicked by the water meaning that the condition forming dunes both on Venus and in our seas could be a close match. This theory has been supported by recent evidence. For instance, astronomical data suggests the dunes on Venus are between 40 and 80 metres tall, whereas aeolian (wind blown) dunes on Earth typically grow to a height of 200 metres. Contrastly, below sea level where particles move differently, dunes tend to be smaller and more like those on Venus.
“The results of this paper have already started to have the desired effect of bringing the marine and the planetary aeolian communities together to talk about the research and how it applies to thicker atmosphere bodies in the solar system,”
– Lynn Neakrase
Researchers believe that by studying the ocean’s patterns and its effects on dune formation they can gain an understanding of dunes on Martian soil, an understanding that could extend to other regions of the solar system such as Titan, Saturn’s moon, that like Venus has a thick atmosphere. Finally, this theory highlights that sometimes in order to understand other celestial bodies we need look no further than the surface of our home even if the clues aren’t where we might expect.
– GeologyHub
GeologyHub 