Mars, the red planet, has been the subject of ridicule and fascination for years. It’s a planet with a meager 10% of Earth’s mass, no magnetic field, and a paper-thin atmosphere. One could say Mars is a planetary underachiever. So, what on Earth (pun intended) are we doing there? Simple. We’re searching for life. Despite its shortcomings, Mars might hold clues to understanding whether life once thrived on its surface – or whether it still does. And with NASA’s Perseverance rover leading the charge, we are setting the stage for future human missions to the Martian surface.
Perseverance: The Mars Rover with Grit
Affectionately known as “Percy,” Perseverance landed on Mars about a year and a half ago in the Jezero Crater, a location selected because scientists believe it was once home to a lake. A lake on Mars! The crater’s intriguing landscape hints at a watery past, a tantalizing clue that life may have once existed there.
Mars is fascinating, but it’s no paradise. Its surface is now a dry, dusty desert. However, the presence of surface features resembling channels and valleys suggests that water once flowed across its surface. Mars has polar ice caps, which contain water ice, and scientists believe that ice may also lie beneath the planet’s surface. This ancient water is the key to understanding whether life ever existed on Mars.
The Struggles of a Small Planet
Mars is a mystery wrapped in a conundrum. With only 10% of Earth’s mass, it lacks the gravitational pull to hold onto a thick atmosphere. It has one-third of Earth’s gravity, meaning that it’s pretty easy for anything on Mars to escape – be it gas, water, or possibly even moons (some theories suggest that Mars could have once been a moon of Jupiter). Without an atmosphere and a protective magnetic field, Mars has been bombarded by solar radiation, making its surface hostile to life as we know it.
However, things weren’t always so bleak. Long ago, Mars had a thicker atmosphere and liquid water, essential ingredients for life. This raises a burning question: Could Mars have once been habitable? And if so, what went wrong?
Mars vs. Earth Is An Unfair Match
Comparing Mars to Earth feels a bit like comparing apples to oranges – or rather, oranges to pebbles. Earth has thrived in the Sun’s habitable zone, with abundant liquid water, a robust atmosphere, and a magnetic field that shields us from harmful radiation. Mars, by contrast, seems to have drawn the short straw. Its smaller size meant it couldn’t hold onto its atmosphere or sustain a magnetic field, both of which are crucial for life.
But Mars has something going for it: location. It’s not too far from the Sun’s habitable zone, and it experiences relatively mild temperatures at its equator, reaching up to 20°C during the day. While the average temperature is much colder, it’s not unthinkable that some form of life could have survived there in the past, or even still exist today.
Water, Water Everywhere (But Not a Drop to Drink)
Mars’ landscape tells the story of a once-wet world. Around 3 to 3.5 billion years ago, Mars had flowing rivers, lakes, and maybe even seas. It’s hard to believe when looking at its barren surface today, but the geological evidence is clear. Ancient river valleys, deltas, and lake beds all suggest that Mars once had a more hospitable climate.
Scientists now know that volcanic activity played a big role in Mars’ past. The planet’s massive volcanoes, like Olympus Mons (the largest volcano in the solar system), likely contributed to a more temperate climate in Mars’ early years. This volcanic activity, combined with asteroid impacts, might have warmed Mars just enough to sustain liquid water on its surface for millions of years.
So, what does this mean for life? On Earth, life emerged about 3.8 billion years ago, around the same time Mars might have had liquid water. Could Mars have followed a similar path? We don’t know yet, but scientists are optimistic that Mars may have hosted microbial life in its past.
On the Hunt for Life
The Perseverance rover is a technological marvel and humanity’s best chance yet to find signs of past life on Mars. It’s currently exploring the Jezero Crater, an ancient lakebed that was once fed by a river. If life existed anywhere on Mars, this crater is a prime candidate.
One of the rover’s key missions is to drill into the Martian surface, collect rock samples, and store them for a future mission to retrieve. These samples, safely preserved in sealed tubes, will one day be brought back to Earth, offering scientists the opportunity to study them up close.
But Percy isn’t just a rock collector. It’s also testing new technologies that could pave the way for human exploration. For instance, its MOXIE experiment is testing whether oxygen can be generated from Mars’ carbon dioxide-rich atmosphere. If successful, this could be a game-changer for future missions, providing astronauts with a source of breathable air and fuel for the journey back home.
The Human Factor: Astronauts on Mars?
Sending humans to Mars is no easy feat. The planet is far – really far. A round-trip journey to Mars would take about two years, with astronauts exposed to dangerous cosmic radiation along the way. Once on Mars, they’d face a host of other challenges, including a lack of breathable air, freezing temperatures, and the need to build habitats from scratch.
NASA’s Artemis missions to the Moon are seen as stepping stones for a future manned mission to Mars. By establishing a base on the Moon, astronauts can gain valuable experience living and working on another world before tackling the more challenging environment of Mars.
Mars and the Future of Humanity
While robots like Percy are doing an incredible job exploring Mars, there’s something undeniably magical about the idea of humans setting foot on the red planet. The Apollo missions to the Moon were transformative moments in human history, and a manned mission to Mars would be even more profound. It’s not just about the science – it’s about the symbolism. When humans venture beyond Earth, it represents our collective drive to explore, understand, and conquer the unknown.
If we do eventually land astronauts on Mars, it could unite the world in a way that few events can. Imagine an international team of astronauts working together on the surface of another planet. It’s the stuff of dreams – but it’s also becoming increasingly possible.
Mars as a Mirror
As we push further into space, it’s important to remember what we’re leaving behind. Mars is a harsh, unforgiving world, and even with the best technology, it would be incredibly difficult to live there. Earth, by contrast, is a paradise in the cosmos, with just the right conditions for life to thrive. Mars missions remind us of how precious our own planet is – and how important it is to protect it.
In the end, Mars is more than just a scientific curiosity. It’s a mirror, reflecting our desires, hopes, and dreams. We may not find life on Mars, but the search itself is a testament to humanity’s boundless curiosity and determination. And who knows? Maybe one day, as we stand on the surface of Mars, we’ll look back at Earth and realize just how special our little blue planet really is.
