In some ways, Mars is like Earth’s twin. It’s about the identical measurement. There’s ice at each its poles. The Purple Planet additionally has 4 seasons as Earth does. And there are volcanoes, windstorms and even little mud devils much like these you would possibly see on a gravelly highway.
However in lots of extra methods, Mars is nothing like Earth. Mars had two moons, Deimos and Phobos. Many of the ice at is poles is fabricated from water, however a few of it’s made out of frozen carbon dioxide. The Martian environment could be very skinny. The truth is, it incorporates so little oxygen that creatures from Earth couldn’t survive on its floor with out numerous assist.
No human has traveled to Mars — but. However spacecraft have been exploring the Purple Planet for many years. That’s how we all know that Mars was as soon as a watery world. It had lakes, seas, rivers and oceans. Now these are all gone. However what occurred to Earth’s twin? And most mysteriously, did life as soon as exist on the Purple Planet?
On August 5, 2012, NASA’s Mars Science Laboratory — higher generally known as the Curiosity rover — landed on Mars. Its mission: to determine whether or not Mars was as soon as a spot the place dwelling issues may survive. The Curiosity mission was imagined to final solely a single Mars yr, the equal of 687 days on Earth. However the rover continues to be exploring greater than 10 years (that’s 5 Martian years) later!
So what has Curiosity been as much as? We’ll let the rover take it from right here.
Hello everybody! I’m so excited to inform you about my adventures.
Observe the water
I began my journey in a spot known as Gale Crater. It’s an enormous crater, stretching 154 kilometers (96 miles) broad. Within the heart is a mountain known as Mount Sharp. NASA informed me to land right here as a result of planetary scientists thought Gale Crater used to carry a lake full of water. The Mars Reconnaissance Orbiter and different spacecraft had taken footage that confirmed options that regarded lots like previous, dried-up lakes on Earth.
After I obtained right here, I analyzed some rocks in Gale Crater with my onboard devices. And I discovered minerals that had water locked up of their crystal construction.
With the information I collected, the science and engineering groups again on Earth “had been capable of affirm that Gale Crater was a lake,” says Tanya Harrison. She’s a planetary scientist and Mars skilled who works at a satellite tv for pc information firm known as Planet Labs in San Francisco, Calif.
You’re most likely considering, who cares about water? However life, at the very least as we all know it, wants water. On Earth, the place there’s water, scientists all the time discover life. So if we wish to discover out if Mars ever had life, it is sensible to go to the place there was water.
Proof within the rocks
Have you learnt what else most dwelling issues want? Oxygen! Plenty of oxygen. On Earth, 21 % of the environment is oxygen. You’re respiratory it proper now. However on Mars, the environment is nearly solely carbon dioxide. Solely 0.13 % is oxygen.
One of many instruments I dropped at Mars was a laser. I used it to review the composition of rocks and I discovered molecules known as manganese oxides. These molecules include the weather manganese and oxygen. Manganese oxides kind the place there’s numerous oxygen.
Harrison says my discovery of manganese oxide in Mars’s rocks tells scientists “that sooner or later in Mars’s previous, there was numerous oxygen within the environment, which is nice for many life as we all know it.”
The place there was water and oxygen, there might need been life.
Large natural molecules
A couple of inches under Mars’s floor, I discovered one thing actually thrilling: items of huge, natural molecules. You might need heard individuals describe meals as “natural.” However in science, natural describes a molecule fabricated from carbon and infrequently hydrogen and oxygen. Some natural molecules additionally include nitrogen or phosphorous.
Your physique, plus all different dwelling issues, include many natural molecules. These molecules make up your cells, offer you vitality and extra. So it’s fairly thrilling that I discovered items of those molecules. However that doesn’t imply I discovered historic life.
It’s kind of like when you opened your pantry door and located eggs, flour and chocolate chips. A chocolate chip cookie may very well be made utilizing these components, however you didn’t really discover a cookie.
Up within the air
Talking of natural molecules, I hold sensing a fuel known as methane in Mars’s environment. Methane is a small, natural molecule comprised of a carbon atom and 4 hydrogen atoms.
On Earth, there are just a few methods to get methane, Harrison says. Methane can come from dwelling issues, like cow burps and some farts. There are additionally some microbes that make methane. That’s why detecting methane in Mars’s environment is so intriguing. What if there are microbes simply beneath Mars’s floor making methane?
However earlier than you get too excited, methane can kind different methods, too. They usually don’t all contain life. For instance, when sure rocks work together with water, they set off a geological course of. Known as serpentinization (Sur-PEN-tin-eye-ZAY-shun), it turns these rocks flip right into a mineral known as serpentinite. Alongside the way in which, this course of releases methane.
Scientists suppose that rocks deep, deep below Mars’s floor is likely to be interacting with — you guessed it — water! So even when microbes aren’t creating Mars’s methane, realizing there is likely to be water below the floor nonetheless provides us hope.
My mission isn’t over but. I plan to maintain exploring for years to come back. However I’ve already performed what I got down to do. I’ve proven that Mars was as soon as a planet on which life may have advanced.
However don’t simply take my phrase for it. Take heed to Ashwin Vasavada. Considered one of Curiosity’s lead scientists, he works at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. He says my explorations have “revealed that every one the circumstances had been proper to help life about 3 billion years in the past.” He provides that “we don’t know if life ever took maintain on Mars, nevertheless it’s fascinating to know that Mars as soon as had that probability.”
By the way in which, even once I’m performed investigating, you’ll nonetheless be studying extra about Mars. My cousin, a rover known as Perseverance, landed on Mars in February 2021. And a Chinese language rover named Zhurong began its explorations the next Might. We’re simply the newest in a sequence of house robots to discover the Purple Planet. And there are extra to come back.
