NASA’s Perseverance rover has made history by capturing the first-ever photo of visible auroras on Mars. The stunning image shows green lights shining in the Martian sky after a powerful solar storm, defying previous assumptions that such a phenomenon was impossible on the Red Planet.
The rover snapped the photo on March 18, 2024, roughly three days after a coronal mass ejection (CME) erupted from the sun and collided with Mars’ magnetic field. This event excited the gas in the planet’s atmosphere, causing it to emit light similar to Earthly auroras. The resulting green lights are believed to be visible only at night and are thought to be the first auroras anywhere in the solar system captured using only visible wavelengths of light.
The discovery has raised hopes that future astronauts may one day witness auroras on Mars firsthand. Analysis of the image revealed that the green hue was caused by excited oxygen molecules, which make up a small portion of the Martian atmosphere. The weak light from the auroras is barely visible due to high levels of dust in the air.
While humans might not be able to see such weak auroras, researchers believe that under certain conditions, they may become visible to the naked eye in the future. Another type of green light, known as airglow, can also occur near Mars’ poles and may be visible to astronauts. This phenomenon is caused by oxygen molecules cooling down and recombining, releasing excess energy.
This discovery adds to a growing list of extraterrestrial auroras detected on other planets in the solar system. Every other solar system world with an atmosphere has some form of extraterrestrial aurora, triggered mainly by charged solar particles or violent space weather events.
Source: https://www.livescience.com/space/mars/lights-on-mars-nasa-rover-photographs-visible-auroras-on-red-planet-for-the-first-time