All the dust on Mars can potentially create a 39-feet-thick layer around the Red Planet, and researchers have discovered where it is coming from.
A team of experts at Johns Hopkins University has found that all the dust that is swirling around the planet in a global dust storm that is expected to last until autumn on Earth's northern hemisphere comes from a single geological formation.
The Medusae Fossae Formation, an easily eroded volcanic deposit that extends more than 3,000 miles along the Martian equator is responsible for all the dust swirling around the planet right now.
Volcanic Deposit Responsible For Martian Dust
In a new paper published in the journal Nature Communications, the researchers report that the dust on the surface of Mars is a chemical match to that found on Medusae Fossae.
The formation, which sits in the highland-lowland boundary near the Tharsis and Elysium volcanic areas, was once one-half the size of the United States. However, the Martian winds blowing through the surface of the planet have eroded the Medusae Fossae to around 20 percent. Even then, the formation is still the largest volcanic deposit known to man in the solar system.
Kevin Lewis, assistant professor of Earth and planetary science at JHU and study co-author, says that if it were not for Medusae Fossae, Mars would not be so dusty. Lewis adds that the formation has been continuously eroding for 4 billion years and, essentially, polluting the planet.
Mars is currently experiencing a planet-wide dust storm that has been raging since June. The dust storm has darkened the skies over NASA's Curiosity rover, while Opportunity has gone into hibernation until the dust storm subsides, to keep the fine powdery dust particles from infiltrating instruments and solar panels needed to provide power.
How Does Dust Form On Mars?
On Earth, dust forms when wind, water, ice, volcanoes, meteor impacts, and other forces of nature erode soft rock formations.
However, it is unlikely that streams of water and glaciers have created enormous amounts of dust on Mars. Experts are also ruling out meteor impacts, even though craters are common on the Red Planet. That is because the particles created during impact are far larger and sharper than the floury grains of Martian dust.
"How does Mars make so much dust, because none of these processes are active on Mars?" says Lujendra Ojha, lead author and postdoctoral researcher at JHU.
Although these factors may have played a role, the researchers believe the Medusae Fossae is the biggest culprit of them all.
Chemical Makeup Of Martian Dust
Ojha's team looked into the chemical makeup of the dust on Mars. Data collected from the spacecraft exploring the planet report the same thing: Martian dust is rich in sulfur and chlorine and has a particular sulfur-to-chlorine ratio.
After gathering data from NASA's Odyssey orbiter, which has been circling Mars since 2001, the researchers were able to identify a part of Medusae Fossae that is rich in sulfur and chlorine.
Looking at the yardangs, or the sharp, irregularly-shaped ridges of compacts and lying on the formation, the researchers were able to calculate how much sand has been lost from Medusae Fossae.
According to their calculations, dust on Mars could be as thick as 6.5 feet up to 39 feet.
The abundance of dust particles also contributes largely to the Martian climate. Dust in the atmosphere absorbs solar radiation, which yields higher temperatures in the upper atmosphere while maintaining lower temperatures on the ground.
The contrast in temperature creates more powerful winds that lift up more dust from the surface, creating a never-ending feedback loop that has puzzled scientists to date.