ALL JUST LIKE ON EARTH: evidence of life on Mars exists!

Photo by Harsh Kumar on Unsplash

The Red Planet once had conditions similar to those on Earth! Indirect evidence of life on Mars is growing. The Perseverance rover has discovered mysterious «spots» at the bottom of an ancient Martian lake. They are likely traces of microbial activity.

TWO PLANETS — TWO FORMS OF LIFE

cience continues to accumulate evidence that life once existed on the planet Mars. Of course, this evidence is mostly indirect, since we are dealing with an extraterrestrial reality separated from us by billions of years. Today, Mars is a cold, dehydrated planet without a magnetic field. But what if, once upon a time, it had water, microorganisms, a life-sustaining atmosphere, and a global magnetic field capable of deflecting harmful cosmic rays?

Harvard scientists, for example, have calculated that around 3.9 billion years ago, such a magnetic field still existed on the planet. It was generated by convection in Mars’s iron core, much like what happens on Earth today. The study of cooling and magnetization cycles in Mars’s giant craters suggests that these craters formed after the magnetic field had «shut down». More precisely, they emerged at a time when the planet’s north and south poles had switched places.

MAGNETIC INVERSION — A CATASTROPHIC CAUSE?

This phenomenon is known as magnetic field inversion. It occurs on Earth too, although not cyclically, but spontaneously. That’s why it cannot be predicted. The last time Earth’s magnetic poles flipped was about 780,000 years ago — fortunately, before Homo sapiens existed. Fortunately — because an inversion can last for hundreds of years, weakening the magnetosphere and allowing deadly cosmic radiation to reach the surface.

Perhaps life on Mars did not survive such a global catastrophe. But if the Harvard calculations are correct, Martian and Earth life forms may have coexisted. Since life on Earth is believed to have originated between 4.1 and 3.8 billion years ago, and Mars likely had the right conditions during exactly that period, this parallel emergence of life becomes a real possibility.

WATER BENEATH THE SURFACE DEFINITELY EXISTS!

Mars owes its rusty-red color to iron oxide dust that covers its surface. This dust contains ferrihydrite, a mineral that could not have formed without the presence of water. It is possible that water — and therefore microbial activity — still exists on the planet, but hidden deep beneath the surface, shielded from cosmic radiation. So is Mars merely giving us the illusion of being a waterless desert?

An instrument aboard the artificial satellite Mars Odyssey, while studying the planet’s infrared emissions, detected that certain areas beneath the surface definitely contain ice or even permafrost. NASA’s InSight lander has also made some fascinating discoveries.

By recording seismic waves, it has allowed scientists to map the structure of Mars’s interior. These waves travel at different speeds through different types of rock, which led researchers to hypothesize the existence of «boundaries» at depths of 10 and 20 kilometers. The composition and structure of these layers may indicate the presence of fluid-filled «pockets».

MARTIAN OCEANS AND RIVERS

The presence of water on Mars should not surprise us too much, considering that billions of years ago, the planet was home to entire oceans, and its climate was warm, humid, and clearly favorable to the emergence of life. This became evident after the Chinese rover Zhurong, while scanning Martian soil, discovered ancient beach deposits at a depth of 80 meters — formed by the movement of ocean waves.

Moreover, the sediment accumulation patterns perfectly match those found on Earth. Around 4 billion years ago, rivers flowed into Martian oceans and lakes — the ancient riverbeds have also been identified. The climate resembled Earth’s, the temperature was stable, and the atmosphere was 100 times denser than it is today, with a high concentration of carbon dioxide. So, if Mars is not suitable for life now, it certainly once was. All that remains is to find its traces.

COULD «EARTHLINGS» HAVE ACCIDENTALLY KILLED «MARTIANS»?

Back in the 1970s, after six years of operation on Mars, NASA’s Viking 1 mission led its creators to a clear verdict: there is life on the Red Planet! Not everyone agreed with this conclusion, however. Worse still, astrobiologist Dirk Schulze-Makuch of the Technical University of Berlin stated that life may indeed have existed — but the Viking 1 mission likely destroyed it.

The German scientist pointed out that NASA’s experiments were based on knowledge of Earth’s microorganisms. So, they attempted to detect life by adding water and nutrients to Martian soil. But if there are living organisms on Mars, they likely dwell inside salt rocks — just like microorganisms in South America’s Atacama Desert, which extract moisture from the air and hygroscopic salts. Since excess moisture is lethal for them, the American scientists may have inadvertently killed them all by adding water to the soil.

However, not everyone agreed with the Berlin astrobiologist’s bold theory, noting that traces of organic compounds on Mars are detected even without the use of water. Furthermore, if we do eventually discover microbes there, how can we be sure they’re not of terrestrial origin? For example, it is known that Earth bacteria — whose genome has already significantly evolved — have long inhabited the outer surface of the International Space Station.

«LEOPARD SPOTS» AND «POPPY SEEDS»

Meanwhile, scientists continue to gather new and compelling indirect evidence of Martian life. Not long ago, NASA’s Perseverance rover discovered some highly unusual markings on Martian rocks — specifically, small dark specks dubbed «poppy seeds», and larger ring-shaped «leopard spots» with a lighter center. Some astrobiologists interpret these features as potential remnants of microbial activity on Mars.

The spots are rich in iron, phosphorus, and sulfur. They may have formed when carbon-containing organic compounds in the rock reacted with iron and sulfate minerals. On Earth, such reactions are typically initiated by microbes. However, it’s equally possible that these spots formed without any help from Martian bacteria.

Definitive conclusions remain elusive while the samples are still on Mars inside Perseverance. That’s why scientists are eagerly awaiting their return to Earth for further analysis. Optimists point out that the spots were discovered in Jezero Crater — once a lake into which an ancient river once flowed — suggesting that the conditions for life there could have been quite favorable.

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