Adjacent to our planet in the solar system, Mars is a planet that has held the interest of humans for ages, and has been studied very thoroughly. Its characteristic red shade comes from the oxidizing of iron minerals, and there is a thin atmosphere present around the planet. Mars also holds several records in our solar system too, from the highest mountain (Olympus Mons, which is three times as tall as Mount Everest!) to the deepest valley (Valles Marineris). One very interesting aspect of Mars is the presence of water. And as it turns out, there is a very respectable amount of it. Large quantities of water – although not necessarily liquid – were found just under the surface in some areas, which opens up the opportunity for rovers to drill through and obtain samples.
A very long time ago, the Red Planet looked much different. So different, in fact, that it may have been comparable to how Earth looked. Water flowed freely throughout the planet, and a thick atmosphere let to a warm temperature. Protecting the planet was a magnetic field that made this all possible. Obviously, things have changed since then. But this may make you wonder – was life once possible on Mars?
Through gathering data from the soil and more (using rovers), scientists get closer and closer to an answer. Organic matter that is similar to rocks on Earth was discovered beneath the surface, and this matter makes up the “building blocks of life on Earth” (Koren). Another correlation to Earth lies in the methane concentration of the planet. On Mars, this actually changes with the seasons. Summer in the northern hemisphere sees the highest levels since higher temperatures lead to its release from water-based crystals. Methane on Earth’s seafloor makes it possible for some ecosystems to exist.
The Downfall of Mars
Well, what happened? How was this promising paradise stripped of its vigor? The answer lies in the magnetic field. Once it disappeared, the atmosphere gradually became thinner and thinner until it reached its current, weakened form. The effect keeping the magnetic field intact required a liquid outer core, and due to interior cooling, this was no longer the case. The lower mass and density of the planet compared to Earth only accelerated the process.
Before I end this post, I want to mention a theory about the early state of Mars. As we know, liquid water was present throughout the planet’s surface. Researcher Cole Brown and scientist Darren Williams, both who were from Penn State (We are!), proposed a model in which Mars started near the orbit of Venus, and subsequently moved outward in its orbit as time went on. Although they admit it was unlikely, they stated that it was still possible.
This was really neat to read! I knew some recent facts about Mars, such as the discovery of water, stuff about the magnetic field and atmosphere, but I learned quite a bit from the post. It made me want to do a bit more research into the state of being on Mars and other research out there! Actually, my first thought while reading the post was the idea of a fiction novel set on Earth in the future where the magnetic field is weakening and the Earth is undergoing the process of turning into a planet like Mars haha! Not realistic at all but fun to imagine.
There are many possibilities for how our solar system started. Some scientists at Stanford conducted hundred of thousands of simulations of the early years of our solar system. There were some very interesting results, including many where Jupiter became a dwarf star, but that’s besides the point. When it comes to mars many simulations show that the cooling was caused because it became less geologically active. Geological activity is required for a magnetic field, so the slow cooling and began and the planet died. It’s really interesting to think about, especially when some simulations show that life could have actually started on mars and then an asteroid impact sent bacteria to earth.
Once we get people on Mars, I think a really cool experiment would be to get common bacteria from Earth (like E. Coli or strep) and let it grow in a controlled way on the Martian surface. It would be interesting to see if the bacteria would be able to survive at all, and the differences in DNA that would pop up if it did.