Salt Water on Mars: A New Indication of Life on the Red Planet
We might not be alone in the universe after all.
For years, a significant debate in the Space Community has been whether there is life on Mars. While to date, no evidence of actual life has been found on Mars; habitable conditions have been discovered after years of exploration.
However, habitable conditions on Mars are not sufficient indicators that life ever existed or could exist on the Red Plane. That is up to us to figure out.
Early Supposition
In the 19th century, scientific research for evidence of life on Mars began with telescopes, which continue till today. However, the primary difference between explorations in the past and today is that in the past, most of the theories were based on fantasies.
In contrast, current investigations are based on finding similarities with the Earth. Hence, the areas of interest that could indicate life on Mars include
- the search for water,
- chemical components in the soil, and
- the composition of the air (and gases) in the planet’s atmosphere.
So what led to thinking that life could have existed or exists today on Mars?
The explanation to this query also lies in the similarity between the Earth and Mars, which was also noticed by the astronomer William Herschel and others in the mid 17the and early 18th centuries. William Herschel discovered the polar ice caps of Mars in the 17th century.
Later research confirmed that Mars has a relatively cold climate with no continental drift. Mars is likely the prime candidate for the possibility of life due to its abundance of prebiotic conditions, likely dating back billions of years.
After previous theories of the presence of water were confirmed by the Phoenix in 2008 and Curiosity Rover in 2012, searches began for the existence of soil and air that could support life.
Salt Water on Mars?
Despite the presence of water or possibly soil that suggests the existence of life, it is not surprising that more than a few parameters are needed for life to be found. Currently, scientists are using 2 ecological approaches to determine the level of habitability.
This method works because by adding specific parameters, it is possible to determine the completely inhabitable areas, eliminating a vast area that could have slowed down the search for life. This allows scientists to work on finding evidence for more habitable places.
While this method was still being experimented with, in September 2006, the Mars Reconnaissance Orbiter was capturing high-resolution pictures of the surface of Mars. In 2011, it captured a photo that would change our perspective on life on Mars forever.
The probe captured a picture of long streaks on the slopes of the Red Planet. The most puzzling part about this remarkable discovery was that the streaks would disappear and reappear continuously. With no one having the slightest idea about what they were, the search for life became much more difficult.
The first explanation was that the powerful storms that raged on Mars had caused these streaks to form. As the Sun heats the surface of the planet, there are more and more dust storms each year. Hence, it was obvious that the storms would be held responsible for these mysterious streaks.
However, these storms are too strong to leave behind any signs. They would have swept the surface clean instead of leaving behind localized marks. So the confusion increased after a likely explanation was deemed incorrect.
After months of experiment and research, a possible explanation was found. By linking the similarities between Earth and Mars, it was suggested that the streaks resulted from a phenomenon also present on Earth.
The scientists explained that such streaks were formed due to the interaction of water and salt in a desert setting. In 2015, a NASA probe photographed streaks in another crater. It also picked up the spectrographic signature of salt.
When the probe passed the area again after a few months, the lines had become more prolonged, with an extensive patch of salt!
This bewildering event took the world by storm when only one possible explanation appeared. Water would have had to flow out and deposit the salt. But even this didn’t make sense. Why?
Because it is a well-known fact that there cannot be any standing water on Mars due to the pressure not being high enough and the temperature being too low, this meant that even if water flowed out, it would have frozen. Mars had been rendered too cold and dry for water to flow.
A New Hope
But then, another explanation came along: if a certain amount of a special kind of salt were dissolved in the water, it would allow the water to remain in a liquid state! Further analysis suggested that this salt could only be Perchlorate Salt, which lowers the freezing point of water to -70°C.
Despite this hypothesis answering the query regarding how water could have flowed, it didn’t answer this question: Where did the water initially come from?
One answer to this question was found by observing the direction of the streaks, which showed that the water didn’t flow down the crater; rather, it came from underground.
This huge discovery led to the confirmation of the fact that liquid water is still flowing at the surface of Mars, even today. It also gives hope to the idea that maybe life on Mars is not how we imagined and somehow found a way to adapt to the conditions on the Red Planet.
Further Exploration on the Red Planet
In the past 10 years, evidence suggesting that life could exist on Mars has been overwhelming. In 2013, Curiosity Rover brought more information to indicate the existence of life. This included vital components in the soil that promote life, the most prominent of which was signs of a freshwater lake.
In 2018, NASA announced that Curiosity Rover had found sediments and organic molecules in rocks dating over 3 billion years old. After these discoveries, exploration in soil and sediments came to a halt, with more focus on discovering even more water.
This approach is also in line with NASA’s “follow the water” strategy on Mars and has sparked a new interest in the Space Community.
Perhaps following such strategies will result in scientists finding life or even communities of life on Mars. With NASA’s aim to launch astronauts to Mars in the 2030s, it is unsurprising that within no time, we will have found an answer to the question: is there life on Mars?
