Doctoral dissertation questions a prevailing perception related to dust devils on Mars

Mars, the fourth planet from the sun, fascinates individuals in some ways. For atmospheric researchers it’s an fascinating topic as Mars is probably the most Earth-like planet of our solar system. Since 1976, probes landed on Mars have collected info on its dynamic climate phenomena.

In his doctoral dissertation at Aalto College, Henrik Kahanpää studied measurements of the atmospheric strain on Mars, vital not just for modeling the environment of Mars but additionally for understanding the situations of different planets.

“The climate change has elevated the necessity for modeling the environment of the Earth. The final word take a look at for verifying the validity of Earth’s climate models is evaluating them to fashions of one other planet. Fashions of planetary atmospheres are additionally useful in assessing the situations of exoplanets discovered outdoors our solar system,” says Kahanpää and admits that pure curiosity impressed him to review Mars.

“It’s no coincidence that the rover despatched to Mars by NASA in 2011 and nonetheless performing measurements there may be referred to as Curiosity.”

Finnish know-how for Mars measurements

Kahanpää’s doctoral research started whereas he was working on the Finnish Meteorological Institute. There he was concerned within the improvement of the strain instrument of the Curiosity rover.

The Finnish Meteorological Institute additionally offered a strain instrument for NASA’s Phoenix probe which landed on Mars in 2008. These devices are based mostly on Barocap sensor heads developed by the Finnish firm Vaisala Oyj. Though these are probably the most correct meteorological devices despatched outdoors the Earth, all measurements are affected by uncertainties, particularly beneath harsh and sudden situations corresponding to on Mars.

Kahanpää investigated uncertainty sources affecting these strain measurements and developed correction algorithms to compensate for them. The outcomes have been utilized within the improvement of the strain instrument of NASA’s Perseverance rover working at the moment on Mars. The dissertation confirmed that the floor atmospheric strain of one other celestial physique might be measured with an accuracy of roughly 0.5% by these devices.

“Comparability of the corrected strain measurements of the Phoenix probe to the measurements of NASA’s Viking landers revealed that no measureable modifications have taken place within the Martian local weather between the Nineteen Seventies and 2008.”

Mud devils

Lifting dust into the environment, dust devils are vital for the analysis of the Martian local weather. They’ll have diameters exceeding one kilometer and be over ten kilometers excessive, though normally they’re much smaller.

“On Earth, weak dust devils spin autumn leaves on parking lots, whereas sturdy dust devils resemble tornados. Within the skinny air of Mars, dust devils are a extra important phenomenon as dust lifted from the planet’s floor has a huge effect on the atmospheric flows of Mars.”

Mud storms carry dust into the Martian environment when the planet is closest to the sun. Nevertheless, the environment is dusty additionally when Mars is farthest away from the sun. Mud devils have been suspected to be the reason. Kahanpää’s analysis questions this prevailing notion.

“I searched for indicators of vortices within the climate measurements of Curiosity and came upon that only some of the vortices have been sturdy sufficient to lift dust. Certainly, in keeping with current research it appears that evidently additionally different small-scale phenomena, corresponding to slope winds, are in a position to carry a whole lot of dust into the Martian environment.”

Details about the dust devils is vital for the planning of future Mars touchdown websites as they considerably affect tools on the planet’s floor. The dust devils will also be useful for Mars landers as they might clear up solar panels of probes. Due to this, NASA’s rover Spirit survived on the floor for for much longer than deliberate.