The planet Venus has been witnessing flashes of light. Scientists have been discussing their nature for a long time, and many of them believe that they are lightning that occurs frequently on Venus.
To find out the truth about this “lightning,” research conducted by a team from the University of Colorado Boulder, West Virginia University, the University of California at Los Angeles, and the University of California at Berkeley re-analyzed the signals emanating from the second closest planet to the sun.
In 1978, when NASA’s Pioneer Venus 1 spacecraft entered orbit around Venus, it detected what are known as whistler waves. These electromagnetic waves are usually created on Earth by lightning, which led scientists to assume that the waves were signs of electrical activity on Venus as well.
The new study suggests that the version of Venus may not be what it initially seemed. “There has been a debate about lightning on Venus for nearly 40 years,” explains magnetospheric physicist and lead author of the study, Harriet George of the University of Colorado Boulder, “and we hope that, with our newly available data, we can help reconcile that debate.” .
Whistling waves are defined as very low frequency (VLF) electromagnetic waves, and are given this name due to the way they “whistle” when heard by radio operators.
They are created by the collision of electrons in the atmosphere, which are usually moved by lightning strikes.
This latest study used data collected in 2021 by another NASA spacecraft, the Parker Solar Probe, when it was on its way toward the sun.
Once again, whistling waves were detected, but something was wrong: the waves were heading in the wrong direction.
Instead of exploding into space, as happens with thunderstorms, these waves were directed down toward the planet’s surface. This indicates that lightning is not the main cause of these electrical signals.
“It’s been trending backwards from what everyone imagined over the last 40 years,” said space plasma physicist David Malaspina of the University of Colorado Boulder.
This does not mean that there is no lightning on Venus, but there is unlikely to be much of it, and the abundant whistling waves picked up by rogue spacecraft appear to be caused by other phenomena.
These other processes were not addressed in depth in this study, but scientists suspect that magnetic reconnection may play a role, as magnetic field lines around Venus twist, break, and then come together again.
Studies have debated whether or not pink lightning exists, and this debate has not yet been closed. More detailed data is needed to confirm this, and the Parker Solar Probe still has one more mission to do, giving scientists another opportunity to take a closer look at the weather on Venus.
The study was published in the journal Geophysical Research Letters.
