Aurora on Mars-it sounds like science fiction, but recently it has become hard reality. In March 2024, a unique event was captured by NASA's Perseverance rover: for the first time, aurora on a planet other than Earth has been photographed from the surface in visible light. Not ultraviolet or infrared, but a green glow you could see with the naked eye. What does this discovery mean for future astronauts and for our understanding of the solar system?
What caused the aurora on Mars?
On March 15, 2024, the sun produced a powerful solar flare, followed by a so-called coronal mass ejection (CME): a huge emission of electrically charged plasma. Such events are familiar to us on Earth: they cause northern or southern lights here, when solar particles collide with the Earth's magnetic field.
But Mars has no magnetic field. Yet auroras were observed there. How could that be?
The key lies in another type of aurora: a solar energetic particle (SEP) aurora. In this process, solar particles interact directly with Mars' tenuous atmosphere. In this case, the collisions between solar particles and oxygen atoms caused a green glow at a wavelength of 557.7 nanometers-pretty much within the range of the human eye.
Why this is special
Until now, auroras on Mars had been seen only from orbit, for example by NASA's MAVEN probe. That we are now from the surface can observe, is a breakthrough. Thanks to the precision settings of the SuperCam spectrometer and Mastcam-Z camera from the Perseverance rover allowed the team of Elise Wright Knutsen (University of Oslo) and others to capture this.
Moreover, this means we can now predict space weather on Mars. According to the researchers, it was known three days in advance that the CME would hit Mars-time enough to properly point the cameras.
What does this mean for future manned missions?
Astronauts who will soon land on Mars could thus see this kind of aurora with their own eyes. Provided conditions are favorable-think clear skies and intense solar activity-the skies of Mars could become a spectacular spectacle.
But there is more than aesthetics. Detecting auroras on Mars is of great importance to safety of future Mars travelers. Solar eruptions bring radiation that can be dangerous to humans. If we can predict such events in time, we can better protect astronauts.
The larger context: Mars as an observatory
At telescoop.com, we keep a weekly eye on international space news. And this kind of news fits right into a trend we've been seeing for some time: Mars is not only a destination for exploration, but also a platform for science across the solar system. Think of the meteorite impacts recorded there, the atmosphere monitored day and night, and now the auroras.
That NASA's Perseverance was able to make this observation proves how powerful and versatile this rover is. Since 2021, it has been exploring Jezero Crater, a place where water once flowed and may contain traces of ancient life. But at the same time, he is thus also contributing to our understanding of solar activity and space weather.
And what can we here on earth do with it?
For amateur stargazers, this is a fascinating phenomenon. It shows that auroras are not an exclusively terrestrial phenomenon, but a cosmic process. And that raises new questions. Can we also observe auroras on other planets with tenuous atmospheres, such as Venus? Or even on exoplanets?
Those interested in tracking solar activity and space weather themselves can already do a lot themselves. Consider apps such as SpaceWeatherLive, or using special filters to track solar eruptions. On our website you will soon find a guide for those who want to predict auroras themselves, on Earth and elsewhere.
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