Life on Mars: Our Second Earth?

Besides Earth, have we ever imagined another planet where humans might one day live? Who could have predicted that Mars would be considered our second Earth? Mars has captivated the imagination of both scientists and science fiction enthusiasts for over a century. As the fourth planet from the Sun, it is known as the second smallest planet in our solar system, following Mercury. Mars is located approximately 227.9 million kilometers from the Sun, with an orbital period of 687 Earth days and a day length of 1 day, 0 hours, and 37 minutes. The gravity on Mars is about 3.721 m/s², roughly 38% of Earth’s gravity, which could significantly impact human physiology over extended periods.

Mars is composed primarily of iron, sulfur, and nickel. Interestingly, its atmosphere contains only 0.16 percent oxygen compared to Earth’s 21 percent. The thin Martian atmosphere is largely composed of carbon dioxide (approximately 95%), with traces of nitrogen and argon. This composition raises significant challenges for human colonization. Mars is often referred to as the “Red Planet” due to its iron oxide-rich surface, which gives it a distinctive reddish appearance. Despite being smaller and less massive than Earth, Mars is the planet most similar to our own, making it a prime candidate for potential colonization.

History of Mars

The history of Mars dates back approximately 4.5 billion years, when it was a geologically active planet with conditions potentially suitable for life. Initially, magma oceans flowed on its surface. Around 4.4 billion years ago, Mars developed a magnetic field, which protected its atmosphere from being stripped away by solar winds. A significant event occurred about 4.3 billion years ago when a massive collision resulted in a debris ring forming around the planet, similar to that of Saturn. Approximately 4.2 billion years ago, carbon dioxide (CO2) ice clouds formed, followed by the emergence of water lakes and the onset of rainfall around 4.1 billion years ago.

However, by 3.8 billion years ago, Mars’ molten core cooled, leading to the loss of its water and atmosphere, with the remaining water turning into ice. By 3.1 billion years ago, Mars had transformed into a cold, dead planet. The first recorded observation of Mars was made in 1610 by Galileo Galilei, who observed it through a telescope. Since then, our understanding of Mars has grown exponentially, fueled by advancements in technology and space exploration.

Possibility of Life on Mars

The potential for life on Mars is a captivating subject in astrobiology, especially given its similarities to Earth. Key elements necessary for life—such as water, organic molecules, and energy sources—have been identified on Mars. Scientists have detected a network of long, straight canals on the planet, which sparked early theories about Martian life. Robotic spacecraft began observing Mars in the 1960s, with the Soviet Union launching several missions, although most were unsuccessful. NASA’s Viking 1 Lander marked the first successful landing on Mars on July 20, 1976, revealing the planet’s highest mountain (Olympus Mons) and deepest valley (Valles Marineris) in the solar system.

Olympus Mons stands roughly 27 kilometers high—about three times taller than Mount Everest. In 2001, NASA launched the Mars Odyssey Probe, which discovered significant quantities of water ice beneath the Martian surface. This finding was crucial as liquid water is essential for life as we know it. In 2003, Mars came closer to Earth than it had in the past 60,000 years, prompting widespread public interest. Then in 2008, NASA’s Phoenix lander successfully searched for water, providing evidence of liquid, salty water in the ground, particularly on hillsides. Mars also exhibits features such as polar ice caps, volcanoes, canyons, and seasonal climate changes.

One intriguing observation was the detection of methane in Mars’s atmosphere, announced by NASA in June 2018. Methane can be produced by biological processes, making its presence on Mars particularly exciting for astrobiologists. The ongoing search for signs of life continues, with missions like NASA’s Perseverance Rover actively collecting soil samples and searching for biosignatures.

Challenges to Life on Mars

However, establishing life on Mars would not be without significant challenges. The planet’s atmosphere is thinner than Earth’s and primarily composed of carbon dioxide, which is harmful to humans. Consequently, astronauts would be unable to breathe on Mars and would require spacesuits equipped with oxygen. Although water exists on Mars, it differs from Earth’s drinkable water; Martian ice contains carbon dioxide, and any liquid water is likely salty and not suitable for direct consumption.

Food production would pose another major hurdle for humans on Mars, as growing food is much easier on Earth. Researchers are exploring ways to grow crops in Martian soil, which lacks the necessary nutrients and may contain toxic perchlorates. Innovative solutions, such as hydroponics and aeroponics, could potentially allow for food production in controlled environments.

The 34 million-mile distance between Mars and Earth complicates transportation logistics, making it one of the biggest challenges for human colonization. Furthermore, Mars is a desolate, lifeless, and inhospitable environment. The planet’s gravity is only 38% that of Earth, which could lead to muscle and bone loss for long-term residents. A successful trip to Mars would demand substantial fuel and resources, adding to the complexities of transportation. Astronauts would also have to cope with isolation and boredom during long journeys, which could impact their mental health.

Space radiation is a significant threat on a Mars voyage, as the atmosphere provides little protection against it, posing serious risks to the human body. The final stage of the journey to Mars is particularly perilous, with NASA scientists referring to the descent from Mars’ atmosphere to its surface as “six minutes of terror.” The challenges of living on Mars are numerous and complex, making it imperative to address these issues before establishing a sustainable human presence.

How to Make Mars Earth-Like

Have you heard of terraforming? Terraforming refers to the process of transforming a planet to make it more Earth-like and capable of supporting human life. Can we terraform Mars? Currently, Mars has a cold atmosphere that needs warming. Elon Musk has suggested that it may be possible to terraform Mars by detonating nuclear grenades over its polar caps, a controversial method that would theoretically release CO2 and warm the planet.

Since Mars has a high concentration of carbon dioxide, technology could help reduce this. The atmosphere on Mars is not breathable, so converting carbon dioxide into oxygen is essential. This process has been initiated by a device known as MOXIE, which can extract oxygen atoms from carbon dioxide molecules. MOXIE represents a crucial step toward sustainable living on Mars, producing oxygen from the Martian atmosphere for potential human use.

Additionally, research is ongoing into creating artificial ecosystems that mimic Earth’s biosphere, allowing for the growth of plants and the recycling of air and water. While these concepts are still in the experimental stage, they represent significant strides toward making Mars habitable.

To make Mars our second Earth, significant efforts will be required. International collaboration, advancements in technology, and a deep understanding of Mars’ environment will be essential in overcoming the myriad challenges that lie ahead. With continuous exploration and research, the dream of colonizing Mars may one day become a reality.