On Earth, this static discharge is usually simply an annoyance. However on Mars, anything “rubbing” versus the uber-dry environment– and even the dry soil– can develop a phenomenon called triboelectric charging.
When particular pairs of products, such as a carpet and your shoes rub together, one material quits a few of its electrons to the other product. The separation of charge can create an electrical field. This procedure also takes place naturally at much larger scales in the world as a corona or electrical glow in some cases seen on airplane and ships in electrical storms known as Saint Elmos Fire.
Although the currents generated by a drone or tiny helicopter like Ingenuity are truly small, Farrell said they may be large enough to cause the air around the blades and other parts of the craft to glow a blue-purple color.
” The electrical currents created by the fast-rotating blades on drones are too little to be a hazard to the craft or the Martian environment,” he said in a news release, “however they use an opportunity to do some additional science to enhance our understanding of a build-up of … triboelectric charging.”
The paper, “Will the Mars Helicopter Induce Local Martian Atmospheric Breakdown?” was released in March 2021 in the Planetary Science Journal.
NASAs Perseverance Mars rover took a selfie with the Ingenuity helicopter, seen here about 13 feet (3.9 meters) from the rover. This image was taken by the WASTON video camera on the rovers robotic arm on April 6, 2021, the 46th Martian day, or sol, of the mission. Credit: NASA/JPL-Caltech/MSSS
There has actually been concern about triboelectric charging because on Mars and the Moon, conditions are ideal for this to take place, specifically in the soil. The soil is drier than desert sand in the world, and when products utilized on rover wheels– such as aluminum or steel– rub versus the soil, it might create sufficient electrical charge to produce problems for the crafts electronics. For that reason, grounding systems have actually been established to counteract the concern.
However Ferrell and his group looked at the possibility of this happening for drones or rotocraft on Mars, as well, due to the dryness of the air, as well as the tendency of dust within the Martian air.
The group used laboratory measurements and used computer system modeling to investigate how electrical charge might develop on a drones rotor blades. They found that as the drones blades spin, they can run into the small dust grains in the Martian air, especially when the helicopter is near the surface area and blowing dust around.
As the blades affect the grains, charge is moved, developing on the blades and producing an electrical field. As charge develops to high levels, the atmosphere starts to carry out electricity, a procedure understood as “atmospheric breakdown,” developing a population of electrons that form an enhanced electrical present that acts to offset the charge or dissipate accumulation on the rotorcraft.
Because the Martian atmosphere is very thin– at the surface practically one percent of the pressure of Earths environment at sea level– this makes breakdown most likely. The scientists acknowledge that their result is a forecast, and in some cases nature has other plans.
NASAs Ingenuity Mars Helicopter caught this shot as it hovered over the Martian surface area on April 19, 2021, throughout the first circumstances of powered, controlled flight on another world. It used its navigation video camera, which autonomously tracks the ground during flight. Credits: NASA/JPL-Caltech
” In theory, there ought to be some result, however whether the electron avalanche is strong enough to create a radiance, and if any weak radiance is observable during operations all remain to be identified in future drone flights on Mars,” stated Farrell “In fact, one could even put small electrometers up near the blade and at the legs to keep track of the impacts of any charging. This sort of electrical screen might be of both scientific worth and provide critical input on drone health during the flight.”
Originally published on Universe Today.
For more on this research study, see Martian Atmospheric Breakdown: Helicopters Flying on Mars May Glow at Dusk.
This is an artists idea of a glow surrounding a drone at Mars throughout flight. The radiance, overemphasized for exposure, might take place if the drones spinning rotor blades create an electrical field that causes electric currents to stream in the Martian air around the craft. The currents created by the drone in the atmosphere are small, they may be large enough to trigger the air around the blades and other parts of the craft to radiance a blue-purple color. This procedure also takes place naturally at much larger scales on Earth as a corona or electrical radiance often seen on aircraft and ships in electrical storms understood as Saint Elmos Fire.
NASAs Ingenuity Mars Helicopter caught this shot as it hovered over the Martian surface on April 19, 2021, during the first instance of powered, controlled flight on another world.
This is an artists concept of a glow surrounding a drone at Mars throughout flight. The radiance, overemphasized for presence, might take place if the drones spinning rotor blades generate an electric field that causes electric currents to flow in the Martian air around the craft. The currents generated by the drone in the environment are little, they may be big enough to trigger the air around the blades and other parts of the craft to glow a blue-purple color. Credit: NASA/Jay Friedlander
If the Ingenuity helicopter would fly at night on Mars, its extremely possible the whirring rotors would create adequate fixed electricity in the extremely dry Martian atmosphere to trigger the air around the craft to glow.
” The faint glow would be most visible throughout evening hours when the background sky is darker,” said William Farrell, from Goddard Space Flight Center and lead author of a paper on this subject. “NASAs speculative Ingenuity helicopter does not fly during this time, however future drones could be cleared for evening flight and search for this glow.”
NASAs Ingenuity Mars Helicopter can be seen hovering during its 3rd flight on April 25, 2021, as seen by the left Navigation Camera aboard NASAs Perseverance Mars rover. Credit: NASA/JPL-Caltech
If youve ever mixed your feet throughout a wool carpet on a dry winter season day, and then connected to touch a metal doorknob, youre familiar with the fixed discharge that creates a little zap– a trigger– that leaps between your fingers and the metal knob.