A contentious question that has captivated scientists for decades, “Does Venus, the Sun’s second closest neighbor, experience frequent lightning?” may soon have an answer, thanks to a NASA probe’s accidental data collection. This probe, far from being designed for Venus exploration, was intended to investigate the Sun’s corona and solar winds.
Since the late 1970s, researchers have observed unique atmospheric phenomena on Venus that has fueled the lightning debate. During that time, a NASA spacecraft, Pioneer Venus, orbited the planet and detected countless “whistler waves” from high above the enigmatic surface.
“We’ve had ongoing discussions about the existence of lightning on Venus for almost four decades,” noted Harriet George, who spearheaded the recent study and is an atmospheric and space physics researcher at the University of Colorado Boulder. Now, our recent findings might finally settle that long-standing debate.”
Venus’s proximity in size to our home planet has made it an object of incredible scientific interest. Still, its inhospitably harsh environments and sky-high temperatures, which can soar up to 482 degrees Celsius, make it impossible for human exploration with current technology.
The existence of “whistler waves” on Venus drove the conversation about the presence of lightning on this stormy planet. These waves, often generated by lightning disrupting the electrons in Earth’s atmosphere, are responsible for the creation of spiraling waves that can be heard as whistles through radio equipment.
If similar processes occurred on Venus, one could assume that the planet experienced an overwhelming amount of lightning – around seven times what we observe on Earth. However, new data from NASA’s Parker Solar Probe consistently suggest that Venus’ whistler waves behave differently.
Launched in 2018, the Parker Solar Probe originally set out to investigate solar phenomena but has uncovered surprising evidence about Venus in the process. On one of its seven flybys planned throughout its mission, it gathered data on the planet’s whistler waves.
“Our examination of these waves found they moved in the exact opposite way we originally thought,” revealed David Malaspina, the study’s co-author and an assistant professor at the Laboratory for Atmospheric and Space Physics and the Department of Astrophysical and Planetary Sciences. Contrary to the upward movement associated with Earth’s lightning storms, Venus’ whistler waves descended towards the planet, suggesting a potential influence from magnetic fields.
Though this discovery doesn’t rule out the presence of lightning, it diminishes the likelihood of the planet being blitzed by a rate of lightning storms that far surpasses the Earth’s. The probe is scheduled for its final flyby in 2024, coming as close as 402 kilometers from Venus, promising a further opportunity to gather more insightful data about this planet’s fascinating atmosphere.