NASA’s Perseverance rover recorded the first visible-light auroras ever observed from the surface of another planet, capturing a green glow tied to the oxygen 557.7 nm emission line during a solar storm that struck Mars in March 2024. The detection, made possible by two onboard instruments and a coordinated space-weather alert system, confirms that solar activity can produce the same color of aurora seen in Earth’s night skies on a world with no global magnetic field and an atmosphere less than one percent as dense as our own. The finding, described in a peer-reviewed study and a detailed mission overview, reshapes what scientists know about how energetic particles interact with the thin Martian atmosphere and opens a new way to monitor space weather across the inner solar system.
Why a green aurora on Mars changes the space-weather picture
Every previous aurora detected at Mars had been observed in ultraviolet wavelengths from orbit, invisible to any human eye. NASA’s MAVEN spacecraft first identified widespread diffuse auroras using its Imaging Ultraviolet Spectrograph, and later confirmed that proton auroras were the most common type at the Red Planet. Those discoveries established that Mars experiences aurora-like phenomena, but they left a basic question unanswered: could a solar storm ever produce light bright enough to see from the ground, in colors a person could actually perceive?
The answer arrived after a solar flare and coronal mass ejection on March 15, 2024. When that burst of magnetized plasma reached Mars, Perseverance’s Mastcam-Z camera and SuperCam spectrometer were already pointed at the night sky. The instruments recorded the characteristic green glow of excited oxygen atoms at 557.7 nanometers, the same spectral line responsible for the most common color in Earth’s northern and southern lights. In the Science Advances paper, researchers attribute the emission specifically to the 557.7 nm transition of atomic oxygen, long familiar from terrestrial aurora studies. Detecting it from the Martian surface, rather than from orbit, is a qualitative leap because it proves the emission is intense enough to penetrate the remaining atmosphere and reach ground level.
That intensity depends on a chain of physical conditions. The CME had to carry a magnetic field oriented in a way that could efficiently channel energetic particles into the Martian atmosphere. The particles then needed to collide with oxygen atoms at altitudes where the air is thin enough that excited atoms can radiate before being quenched by further collisions. Scientists describe this distribution with the concept of oxygen scale height, which effectively sets how many oxygen atoms sit at each altitude. If the scale height is too small, there are not enough atoms in the right region to glow; if it is too large, collisions can dampen the emission before photons escape.
The March 2024 event shows that, at least under strong solar forcing, Mars can satisfy this balance. The relationship between CME properties and visible aurora brightness is now something researchers can test directly by comparing future surface spectra with solar-wind measurements archived by NASA’s forecasting offices. That, in turn, could improve models of how often dangerous radiation levels accompany auroras at Mars, a crucial factor for planning future human explorers who might rely on natural terrain or artificial shelters to ride out solar storms.
How Perseverance and NASA’s alert chain captured the 557.7 nm glow
The detection was not accidental. NASA’s Moon to Mars Space Weather Analysis Office, known as M2M SWAO, issued real-time assessments and alerts for Mars missions including Perseverance and MAVEN after tracking the March 15 solar event. From its base at Goddard Space Flight Center, the office uses heliophysics models and multi-spacecraft data to forecast when and how solar eruptions will affect planetary environments. According to the program description, the team’s mandate is to translate those forecasts into concrete guidance for mission operators in deep space.
Those alerts gave the Perseverance science team enough lead time to schedule nighttime observations with both Mastcam-Z and SuperCam before the CME arrived. Mastcam-Z provided imaging of the visible-wavelength aurora, capturing faint green arcs above the horizon, while SuperCam performed spectroscopy that isolated the 557.7 nm oxygen line from the broader spectrum of skyglow and scattered starlight. The combination of a camera and a spectrometer on the same platform gave the team both spatial context and chemical confirmation in a single observation window, reducing ambiguity about whether the signal truly came from auroral processes rather than instrumental noise or reflected sunlight.
Earlier MAVEN data, collected from orbit in ultraviolet, had shown that proton auroras at Mars occur frequently but remain invisible to the human eye. These events happen when energetic protons from the solar wind capture electrons and then excite atmospheric hydrogen, producing ultraviolet emissions. The Perseverance result breaks that pattern by recording light at a wavelength any person standing on Mars could, in principle, see, assuming sufficiently dark skies and adapted night vision. It also demonstrates the value of coordinating surface assets with orbiting spacecraft and Earth-based forecasters, creating a multi-layered observing system for planetary space weather.
The operational chain behind the observation matters as much as the science. M2M SWAO coordinates with the Community Coordinated Modeling Center and multiple mission teams to convert solar-event forecasts into actionable commands for spacecraft across the solar system. For Perseverance, that meant interrupting routine geology campaigns, reorienting the rover’s mast, and configuring exposure times to maximize sensitivity to dim structures in the sky. Without that pipeline, the rover’s cameras would likely have been idle or pointed at rocks during the brief window when the aurora was active, and the historic opportunity would have passed unnoticed.
Open questions about Martian auroras after the March 2024 detection
Several gaps remain in the public record. The full raw Mastcam-Z image files and SuperCam spectra from the event have not been released beyond the summary data and representative plots presented in the Science Advances paper and NASA’s mission summary. Quantitative comparisons between the 557.7 nm intensity recorded at Mars and typical terrestrial aurora brightness are absent from the published sources, leaving researchers without a direct benchmark for how bright the Martian display would appear to a human observer.
The exact coordination timestamps between M2M SWAO alerts, MAVEN’s in situ measurements, and Perseverance’s observation commands have also not appeared in publicly available logs. Those details would allow independent teams to reconstruct the sequence of events, correlate changes in the local radiation environment with the onset of visible emissions, and test space-weather models under real conditions at another planet. For now, the community must infer much of that timing from narrative descriptions and a limited set of figures.
A deeper scientific question sits behind the data gap. Mars lacks a global magnetic field, so energetic solar particles can strike the atmosphere almost anywhere rather than being funneled toward magnetic poles as they are on Earth. Instead, patchy crustal magnetic fields, frozen into the ancient Martian crust, create localized mini-magnetospheres. The geometry of each visible aurora event on Mars is therefore likely shaped by the interplay between these crustal fields and the specific orientation of the incoming CME’s magnetic structure.
Whether visible auroras occur only during the most extreme solar storms or can be triggered by more moderate events remains unresolved. The March 2024 storm was unusually intense, producing elevated radiation levels and widespread ultraviolet auroras detected by MAVEN. If comparable green emissions appear during less powerful CMEs, that would suggest that visible auroras may be a relatively common, if still faint, feature of the Martian sky during solar maximum. Conversely, if no further events are seen from the surface in coming years, it would imply that the threshold for generating visible emissions is high and only rarely crossed.
Future campaigns could address these uncertainties by combining long-term monitoring from Perseverance and other surface assets with continuous solar-wind measurements from MAVEN and improved modeling from M2M SWAO. Coordinated observations during a range of solar conditions would help disentangle the roles of particle energy, atmospheric density, and crustal magnetism in producing the 557.7 nm glow. For mission planners, the payoff is twofold: a better understanding of how Mars responds to the changing Sun, and a practical tool for diagnosing hazardous space weather using instruments already deployed on the surface of another world.
More from Morning Overview
*This article was researched with the help of AI, with human editors creating the final content.
