NASA's Curiosity rover has just sent back data that suggests Mars was once a watery, temperate world that could have possibly sustained life.
Data sent back to Earth from the Curiosity rover on Mars has revealed that the Red Planet was probably much more like our own planet than previously thought. According to a report from Gizmodo, the rover has shown that water used to be abundant on the surface of Mars, creating river deltas, lakes, and sustaining a warm and temperate climate.
Researchers believe that water may have flowed on the surface of Mars for long enough to allow life to begin to develop. Last month, NASA announced that there was very likely liquid water present on Mars. If water is around today, then it’s a safe bet to say that it has been there since the planet’s early days in the solar system.
The most recent discovery of some amazing hydrological features on the surface of Mars was made by NASA’s John Grotzinger and his research crew at the Mars Science Laboratory. Curiosity has discovered evidence of river deltas, standing lakes, and historical climatic data that suggests life had a fair chance at evolving on the Red Planet. The discoveries were published in the journal Science.
Scientists have been trying to study the history of water on Mars for years. The breakthrough made by Curiosity and her controlling team is the discovery of evidence supporting the theory that large impact craters once collected and stored water in massive lakes on the surface of Mars. Curiosity was able to get up-close and personal with some of the features that hinted at the possibility of ancient lakes through satellite images, discovering numerous basin surfaces, or clinoforms.
Curiosity has been studying the Gale Crater, taking samples of the sedimentary rocks left behind. Sedimentary rocks are created when particulates settle at the bottom of a body of water and become compressed together. Sedimentary rocks can offer insight into the ways water once traveled over the surface, which direction it was going, and what was in it at the time. Sedimentary rocks are also a rich source of fossils and microscopic signs of life.
Curiosity sent back data from the sedimentary rock samples it took, and found that even though there was a considerable amount of erosion on Mars’ surface, the basin in the Gale Crater had actually risen. This means that the land had gotten higher as a result of sediments piling up on top of each other over thousands and millions of years. The accumulation of these sediments over time is known as aggradation.
The water that researchers believe used to be in the Gale Crater eventually began to flow in at the northern rim. Water eroded the gravel and sand from the surface of the planet and carried it down into the center of the crater in tiny streams. As these streams flowed, the deposits made their way toward the center of the crater, continually breaking into smaller and smaller pieces. The deposits of these fine grains at the end of the riverbeds offered Curiosity team members a glimpse at an ancient Martian river delta.
Evidence collected by Curiosity shows that these crater lakes existed billions of years ago and held water for 100 to 10,000 years each. This provides ample time for life to develop, or so astrobiologists believe. To date, there still has been no evidence of extraterrestrial life discovered on Mars, but evidence is mounting that the conditions were probably right at one point in time.
The Gale Crater lakebed, currently being analyzed by Curiosity, probably took between 10,000 and 10,000,000 years to fill and deposit its sediments, which means that the lakes on the Red Planet were likely fed by a large groundwater table.
According to the recent finding, “This intracrater lake system probably existed intermittently for thousands to millions of years, implying a relatively wet climate that supplied moisture to the crater rim and transported sediment via streams into the lake basin.”
Curiosity researchers compared similar hydrological formations here on Earth to estimate the age of the Martian lake and riverbeds. While the estimates are far from precise, they show that there was water present on Mars’ surface for long enough to allow life to begin to develop.
Some of the findings have raised speculation about the ancient climate of Mars, but it remains difficult to conclusively say what it was like. According to Marjorie Chan, a geologist from the University of Utah, however, the scientific consensus is that Mars was probably warmer and wetter than it is today. The only way Mars would have been able to sustain life, Chan says, is if the atmosphere were thicker.
Current understandings of the available information can’t explain why Mars likely had a wet and warmer climate, but Curiosity’s findings offer fascinating starting points. The fact that liquid water ran on the surface for enough time to deposit sediments and create giant formations means that it was likely warm enough for more than a few years.