NASA Rover Observes Aurora on Mars in Visible Light for 1st Time

The first visible-light image of a green aurora on Mars (left), taken by NASA's Perseverance rover, is seen next to a comparison image showing the night sky without the aurora but featuring the Martian moon Deimos (right), in this image released by NASA on May 14, 2025. NASA/JPL-Caltech/ASU/MSSS/SSI/Handout via REUTERS
The first visible-light image of a green aurora on Mars (left), taken by NASA's Perseverance rover, is seen next to a comparison image showing the night sky without the aurora but featuring the Martian moon Deimos (right), in this image released by NASA on May 14, 2025. NASA/JPL-Caltech/ASU/MSSS/SSI/Handout via REUTERS
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NASA Rover Observes Aurora on Mars in Visible Light for 1st Time

The first visible-light image of a green aurora on Mars (left), taken by NASA's Perseverance rover, is seen next to a comparison image showing the night sky without the aurora but featuring the Martian moon Deimos (right), in this image released by NASA on May 14, 2025. NASA/JPL-Caltech/ASU/MSSS/SSI/Handout via REUTERS
The first visible-light image of a green aurora on Mars (left), taken by NASA's Perseverance rover, is seen next to a comparison image showing the night sky without the aurora but featuring the Martian moon Deimos (right), in this image released by NASA on May 14, 2025. NASA/JPL-Caltech/ASU/MSSS/SSI/Handout via REUTERS

NASA's Perseverance rover has observed an aurora on Mars in visible light for the first time, with the sky glowing softly in green in the first viewing of an aurora from any planetary surface other than Earth.

Scientists said the aurora occurred on March 18, 2024, when super-energetic particles from the sun encountered the Martian atmosphere, precipitating a reaction that created a faint glow across the entire night sky. Auroras have been observed previously on Mars by satellites from orbit in ultraviolet wavelengths, but not in visible light.

The sun three days earlier had unleashed a solar flare and an accompanying coronal mass ejection - a huge explosion of gas and magnetic energy that brings with it large amounts of solar energetic particles - that traveled outward through the solar system. Mars is the fourth planet from the sun, following Mercury, Venus and Earth.

Scientists had simulated the event in advance and prepared instruments on the rover to be ready to observe the expected aurora. Perseverance has two instruments that are sensitive to wavelengths in the visible range, meaning they detect colors human eyes can see. The researchers used the rover's SuperCam spectrometer instrument to identify exactly the wavelength of the green glow and then used its Mastcam-Z camera to take a snapshot of the softly glowing green sky.

An aurora forms on Mars the same way as on Earth, with energetic charged particles colliding with atoms and molecules in the atmosphere, exciting them, and causing subatomic particles called electrons to emit light particles called photons.

"But on Earth, the charged particles are channeled into the polar regions by our planet's global magnetic field," said Elise Wright Knutsen, a postdoctoral researcher at the University of Oslo's Center for Space Sensors and Systems and lead author of the study published this week in the journal Science Advances.

"Mars has no global magnetic field so the charged particles bombarded all of Mars at the same time, which leads to this planet-wide aurora," Reuters quoted Knutsen as saying.

The green color occurred because of the interaction between the charged particles from the sun and oxygen in the Martian atmosphere. While auroras can be brilliant, as often seen in Earth's northernmost and southernmost regions, the one observed on Mars was quite faint.

"This specific aurora we observed on March 18th of last year would have been too faint for humans to see directly. But if we get a more intense solar storm, it could become bright enough for future astronauts to see. And with a camera, such as an iPhone, you would clearly see it, rather like how an aurora on Earth is always brighter in images than with the naked eye," Knutsen said.

This particular event did not impact Earth.

All the planets with atmospheres in our solar system experience auroras.

"Various types and wavelengths of aurora have been observed previously from Mars-orbiting satellites. All previous observations have been in the UV, but they have had wildly different shapes. From the global, diffuse aurora we observed now, to discrete arcs and patches near the crustal fields (regional magnetic fields) in the south, and large-scale sinuous shapes," Knutsen said.

If astronauts from Earth visit Mars and perhaps establish a long-term presence on the planet's surface, they may be treated to a nighttime light show.

"During a more intense solar storm, producing a brighter aurora, I think a sky which glows green from horizon to horizon will be eerily beautiful," Knutsen said.

"The aurora will appear as a soft green glow covering more or less the whole sky," Knutsen added. "Dust in the lower part of the atmosphere would obscure some of the light towards the horizon, and if you looked straight up it would also be fainter simply because looking at a slant angle will allow you to see through a thicker section of the atmosphere that is emitting the aurora."



Disasters Loom over South Asia with Forecast of Hotter, Wetter Monsoon

The Himalayan mountain range of Annapurna and Mount Machapuchare (top, C) are pictured from Nepal's Pokhara on June 7, 2025. (Photo by Prakash MATHEMA / AFP)
The Himalayan mountain range of Annapurna and Mount Machapuchare (top, C) are pictured from Nepal's Pokhara on June 7, 2025. (Photo by Prakash MATHEMA / AFP)
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Disasters Loom over South Asia with Forecast of Hotter, Wetter Monsoon

The Himalayan mountain range of Annapurna and Mount Machapuchare (top, C) are pictured from Nepal's Pokhara on June 7, 2025. (Photo by Prakash MATHEMA / AFP)
The Himalayan mountain range of Annapurna and Mount Machapuchare (top, C) are pictured from Nepal's Pokhara on June 7, 2025. (Photo by Prakash MATHEMA / AFP)

Communities across Asia's Himalayan Hindu Kush region face heightened disaster risks this monsoon season with temperatures and rainfall expected to exceed normal levels, experts warned on Thursday.

Temperatures are expected to be up to two degrees Celsius hotter than average across the region, with forecasts for above-average rains, according to a monsoon outlook released by Kathmandu-based International Center for Integrated Mountain Development (ICIMOD) on Wednesday.

"Rising temperatures and more extreme rain raise the risk of water-induced disasters such as floods, landslides, and debris flows, and have longer-term impacts on glaciers, snow reserves, and permafrost," Arun Bhakta Shrestha, a senior adviser at ICIMOD, said in a statement.

The summer monsoon, which brings South Asia 70-80 percent of its annual rainfall, is vital for agriculture and therefore for the livelihoods of millions of farmers and for food security in a region that is home to around two billion people.

However, it also brings destruction through landslides and floods every year. Melting glaciers add to the volume of water, while unregulated construction in flood-prone areas exacerbates the damage.

"What we have seen over the years are also cascading disasters where, for example, heavy rainfall can lead to landslides, and landslides can actually block rivers. We need to be aware about such possibilities," Saswata Sanyal, manager of ICIMOD's Disaster Risk Reduction work, told AFP.

Last year's monsoon season brought devastating landslides and floods across South Asia and killed hundreds of people, including more than 300 in Nepal.

This year, Nepal has set up a monsoon response command post, led by its National Disaster Risk Reduction and Management Authority.

"We are coordinating to stay prepared and to share data and alerts up to the local level for early response. Our security forces are on standby for rescue efforts," said agency spokesman Ram Bahadur KC.

Weather-related disasters are common during the monsoon season from June to September but experts say climate change, coupled with urbanization, is increasing their frequency and severity.

The UN's World Meteorological Organization said last year that increasingly intense floods and droughts are a "distress signal" of what is to come as climate change makes the planet's water cycle ever more unpredictable.