New Delhi: NASA’s Perseverance rover was able to find green spots on Mars at the area called “Serpentine Rapids.” The SHERLOC WATSON camera installed on the rover got these colourful discoveries on 19 August 2024, as it showed Martian rocks in red, green, and white. Of these features, the most prominent one is a large green area, about 2 mm in diameter, set against the reddish-cut stone. This came about after Perseverance scraped a 5-centimetre area in a red rock outcrop known as “Wallace Butte” and found a host of colours no one expected to be there.
These red rocks at Serpentine Rapids look like ‘red beds’ on the earth, which are red due to oxidised iron (Fe3+), the compound that gives the colour of rust and blood. Notably, green spots in these earthly rocks appear when water invades the sediment and initiates a reduction reaction that changes the iron oxide to a green colour. In some cases, this chemical process may include microbial action; nevertheless, green areas on the Earth may also appear due to the oxidation of organic remains and/or independent reduction of iron by sulphur-iron bacteria.
Although SHERLOC and PIXL instruments on board Perseverance did not capture green patches with their targets, researchers are interested in identifying other similar surface areas. On Earth, such low iron spots act as indicators of previous conditions that were hydrated, but it is still unknown whether Mars has gone through similar geochemical evolution.
Making its Ascent: Perseverance’s Journey
The new discovery has come at a time when Perseverance is about to embark on a difficult phase of driving out of the Jezero Crater, which the rover has investigated for more than two years of Martian ground rocks. The NASA’s Science Team is driving the rover through challenging grounds, but the further possibility of discovering more surprises at the crater edge gives them hope. Researchers believe that more exploration of this steep area may help them understand the Martian context of the old environment, especially as Perseverance looks for rock types that have been altered by water or other processes in the distant past.
Perseverance keeps on moving ahead with each Martian sol, and with each sol, it is revealing more and more of Mars’ geology. Every find, from ‘leopard spots’ to green areas, contains some information that would help researchers get closer to the Martian past and its ability to sustain extraterrestrial microorganisms.
