Mysterious Blobs in Mars' Red Landscape: NASA's Rover Detects Puzzling Stone
The "mysterious" red stone, as NASA described it in a recent statement, couldn't be fully analyzed due to the limitations of Perseverance's tools. However, the rock's features hint at how it might have formed on an older, wetter Mars.
Perseverance arrived on Mars in February 2021, with a primary goal: to examine a dried-up river delta along the edge of a multi-billion-year-old lake for indications of ancient microbial life. Mars is the only planet in our solar system with active landers exploring its surface, uncovering evidence of its ancient past.
Despite Mars having extreme temperature fluctuations and being extremely arid, scientists believe it had large bodies of liquid water on its surface billions of years ago. One such lake was in Jezero Crater, where Perseverance landed three years ago.
Since then, Perseverance has traversed Jezero's western edge, image-capturing the planet and gathering rock cores and some Martian atmosphere. This evidence is set to be transported to Earth, pending significant funding and determined efforts.
Perseverance's astrobiological search is based on the idea that if life existed on Mars, it would have resembled early life on Earth: microbes surviving in shallow water. These microbes form sedimentary concretions as they live, which then fossilize into distinctive, Sol Lewitt-like patterns. On Earth, these rock fossils, known as stromatolites, continue to form today. Earlier this year, researchers discovered the oldest fossilized photosynthetic structures yet, in 1.75-billion-year-old rock in northern Australia, where even more ancient stromatolites are also present.
In July, Perseverance spotted "leopard spots" on Mars in bands of hematite and calcium sulfate. NASA scientists believe these spots could indicate that the rock once contained organic compounds.
Lastly, Perseverance investigated another intriguing target: the red rock with green spots. Though not definitive proof of alien life, the rock offers insights into Mars' iron-rich past.
The rock's redness is likely due to oxidized iron. The Perseverance team, thus, wanted a closer look. Using an abrading tool, the rover removed a 2-inch-wide (5-centimeter-wide) chunk of the rock's surface to reveal the stone beneath, which had not been affected by the windy conditions on Mars' surface.
The green spots in the rock are "fairly common," according to the NASA statement. They occur when water permeates the iron-rich sediment before it turns into rock, causing the iron to oxidize and turn green. On Earth, microbes can catalyze this reaction, though it can also occur due to decaying organic matter or interactions between sulfur and iron. Whatever the cause, analyzing the rock could provide insights into Mars' watery past, potential life on the planet, or its evolution.
Given the potential, the green-flecked deposit warranted further investigation. However, there wasn't enough space around the rock sample for Perseverance to deploy its instruments, so the rock's composition couldn't be studied in greater detail.
Let's hope more rocks with similar features come up in Perseverance's future. The rover is currently climbing the rim of Jezero Crater, moving out of its Martian nest towards a deeper understanding of our neighboring, arid world.
In the future, advancements in science and technology might enable us to analyze the green-flecked rock in greater detail, possibly revealing more about Mars' watery past and potential life. Furthermore, future missions to Mars could potentially bring more rocks with similar features, providing even more insights into our neighboring planet.
