First visible-light aurora on Mars detected from the surface

NASA’s Perseverance rover has captured a visible aurora from the surface of Mars for the first time. It recorded a green glow produced by atomic oxygen using its SuperCam spectrometer and Mastcam-Z camera. This emission, familiar from Earth’s auroras, had not been confirmed on Mars in visible light until now.

The visible aurora originated from a 557.7 nanometer green emission line associated with atomic oxygen. This transition was predicted to exist in the Martian upper atmosphere but had not been detected before. Previous auroras on Mars were observed only from orbit and in ultraviolet wavelengths.

The discovery followed a solar event forecast that prompted targeted observations. Scientists from NASA, ESA, and several universities were monitoring an active region on the Sun. On March 15, a C4.9-class solar flare released a coronal mass ejection (CME) traveling over 1 100 km/s (683 mi/s). The CME reached Mars three days later, driving energetic particles into the planet’s atmosphere and triggering auroras on the nightside.

The aurora was observed at Jezero Crater, where Perseverance is currently stationed. SuperCam detected the spectral signal at 06:46 UTC, measuring about 101 Rayleighs at a 20° elevation angle. This intensity suggests a source altitude between 60 and 140 km (37 to 87 miles). Mastcam-Z later confirmed the emission with images showing a faint green-yellow glow that intensified at higher elevation angles.

The aurora was caused by charged particles—mainly electrons and protons—accelerated by the advancing shock front of the CME. This process, known as a gradual solar energetic particle (SEP) event, differs from impulsive solar flares by offering a longer lead time, allowing scientists to plan the rover’s observations in advance.

Only one emission line was observed during this event. Models suggest that stronger solar storms or clearer atmospheric conditions could produce brighter emissions. Under low dust conditions, the green glow could exceed 200 Rayleighs, which is just below the threshold for human visual detection.

To verify the aurora’s origin, the team reviewed earlier data and conducted a follow-up observation on sol 1107. Neither showed the same spectral signature, confirming that the glow was auroral. The results suggest that visible auroras on Mars may occur more frequently than previously assumed.

SuperCam’s result was backed up by Mastcam-Z’s camera data, which showed a consistent increase in green channel brightness at lower elevation angles. The estimated auroral brightness from the surface after adjustments for dust conditions was about 101 Rayleighs.

The results point to the possibility that visible auroras on Mars are more common than assumed. Many may have gone unnoticed in the past because of dust or poor timing. With better forecasts and planning, it’s now potentially possible to observe them from the surface as well as from orbit.

Future missions could use simpler auroral cameras built for this purpose. Narrow-band filters tuned to wavelengths like 557.7 nanometer would come in handy. The Mars Aurora and Dust Camera of the proposed Mars Multispectral Auroral and Thermal Imaging Spectroscopic Survey Explorer (M-MATISSE) mission is a great example of the same.

Elise Knutsen, a postdoctoral researcher at the University of Oslo and lead author of the study reporting the detection, said that this exciting discovery opens up new possibilities for auroral research and confirms that auroras could be visible to future astronauts on the surface of Mars.

References:

¹ NASA Observes First Visible-light Auroras at Mars – NASA – May 14, 2025

² Detection of visible-wavelength aurora on Mars – Elise W. Knutsen, Timothy H. McConnochie, Mark Lemmon, et al. – Science Advances – May 14, 2025 – DOI https://www.science.org/doi/10.1126/sciadv.ads1563 – OPEN ACCESS