Plasma balls are widely used in retail stores around the rich world. If you’ve ever seen one and had the chance to touch it, you’ve seen the plasma bend in the direction of your touch, creating a feeling that you can use electricity like Thor.
This effect does not only occur on earth – wherever charges build up that cause a sufficiently high electrical potential between two points to produce an electrical glow or a corona. Now a team at NASA believes a large build-up of cargo could occur if Ingenuity, Perseverance’s helicopter attendant, soars into the sky.
Image of a plasma ball.
Photo credit: Wikipedia user Diliff
The team led by Dr. William Farrell of the Goddard Space Flight Center has been interested in the electrical properties of the Martian atmosphere for decades and began studying the subject in the early 1990s. There are many reasons to want to understand these phenomena, not the least of which is to understand what impact they could have on a future human colony.
Right now, the ambassadors of humanity to the red planet are robots, and they have their own challenges when exposed to electrical discharges. A special robotic envoy is in a unique position among contemporary Martians when it comes to electrical discharges. Ingenuity operates in a naturally dusty atmosphere and could possibly even create its own miniature cloud of dust when it soars into the sky in a few weeks.
A favorite picture of the effects of static electricity and tribocharging – a cat covered in electrically charged packaging peanuts.
Photo credit: Wikipedia user Sean McGrath
These dust interactions are accompanied by electrical potentials that arise when two dust particles run into one another or into the blades of the rotary wing aircraft. The dust that comes into contact with the blades is likely to cause a phenomenon technically known as “tribocharging”. Usually, people are familiar with this phenomenon by rubbing balloons on their hair and then taping them to a blanket.
Tribocharging itself is unlikely to cause sparks to fly in Earth’s atmosphere. However, the conditions on Mars are different, whose atmosphere has a much lower “breakdown voltage” than that of Earth. While the research team is quick to point out that there is no imminent threat to Ingenuity or the rovers themselves, there is the potential to get interesting data on the electrical potential of the Martian atmosphere.
Image of how the specks of dust interact with Ingenuity’s blades.
Photo credit: Farrell et al.
These data have been a long time coming, as attempts to study the electrical properties of the Martian atmosphere have a history that goes back to the 1990s. Efforts were plagued by the notorious difficulty of actually landing a vehicle on Mars. Attempts to send an instrument that can be examined in detail were abandoned when the Mars Polar Lander mission failed in 1999. This ship was part of the Mars Surveyor program that was launched after the loss of the Polar Lander.
One of these planned but never executed survey vehicles, Mars 03 Surveyor, was supposed to have electrical instruments with which scientists could directly study the electrical properties of the atmosphere. A later mission, ESA’s Schiaparelli lander, would have had similar instruments, but was destroyed along with the lander in a failed landing attempt in 2016.
Artistic rendering of the fancy Schiaparelli lander that would have brought some electrical instruments to Mars.
Photo credit: ESA / ATG
Despite all these setbacks, interest in the subject has not waned. And the launch of Ingenuity allows for a random chance to get at least some data. The counter-rotating blades that the helicopter uses for stabilization will likely create a small Van de Graff generator that charges the helicopter body with high voltages compared to its surrounding atmosphere.
The best way to observe this phenomenon would be with special instruments such as an electrometer or a radio antenna. Instead, on this mission, the best scientists can hope to see Ingenuity launch. Dr. Farrell and his team suggest that this would result in ideal observation conditions at dusk. Mission planners, however, prefer operations with good lighting and calm winds – not necessarily at dusk.
UT video about the challenges of landing on Mars.
Regardless of the start time, Ingenuity’s flight will be mankind’s first controlled flight to another planet. If it takes off with an amazing shine, not only will it be great data for Dr. Farrell and his team deliver, but could also be a spectacular show for those of us who are stuck on the ground.
arXiv – Will the Mars helicopter cause a local collapse of the Martian atmosphere?
UT – This is how Perseverance’s helicopter buddy is used on Mars
UT – lightning detection on Mars
Artistic rendering of ingenuity on site on Mars.
Photo credit: NASA / JPL – Caltech