Dr Naomi Lavelle: Is there (or could there be) life on Mars? – Irish Examiner

If we look to the skies on a clear night we get a glimpse of the expanse of space and the planets beyond our own. It may make you wonder, could humans ever live somewhere other than Earth?

Living in space

If we consider living outside of the Earths atmosphere then we have already achieved this; Russian cosmonaut, Valeri Vladimirovich Polyakov holds the record for the most consecutive days in space. Polyakov stayed aboard the Mir space station for more than 14 months during one trip. The most time spent on a celestial body is a Moon visit in December 1972. During that trip, Harrison Schmitt and Eugene Cernan of NASAs Apollo 17 mission spent more than three days on the lunar surface.

Lunar return

The International Space Station has had continuous human occupancy for more than 20 years (since November 2nd 2000). Now NASA plans to establishing a permanent human presence on the Moon too, within the next decade, with its Artemis program. This should also help to advance other programs aiming to put humans on another planet, Mars.

Living on Mars

If humans are ever to inhabit a planet other than Earth, then Mars is the most likely candidate. The surfaces of Mars and Earth were once very similar. Both had heat, moisture and thick atmospheres. While we retained these ideal living conditions on Earth, things took a turn for the worst for Mars about three to four billion years ago. If we want to live there we would have to work out how to turn back time.

Traveling to the red planet is possible, in theory, and could take between six to nine months. There is a big difference between surviving in a controlled living environment and actually living on a planet though. To really live on Mars we would need to terraform the planet.

Terraforming Mars

Terraforming the red planet would require the creation of a thicker atmosphere with breathable air and soil that can ultimately grow edible plants. Mars does contain a lot of carbon dioxide, most of which is bound in solid form in its polar caps. Even if all this was released into gaseous form, it would not be enough to create an atmosphere thick enough to hold in heat, water and other necessary gases. The latest NASA rover (Perseverance) on its way to Mars should land on February 18, 2021. One piece of equipment included on the Perseverance rover is the Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE), intended to produce oxygen from Martian atmospheric carbon dioxide, on an experimental scale. Even if successful, this technology could only create small amounts of oxygen.

Could plants be introduced as a means of converting carbon dioxide into oxygen? Such plants would require nitrogen rich soil and the right levels of sunlight for photosynthesis. Neither are available. Cyanobacteria may do the job more efficiently, but it would take a long time, and much of the oxygen would still be lost without a thick enough atmosphere. A day on Mars last 25 hours, a year lasts 1.9 Earth years. Mars has four seasons, just like Earth, but they last almost twice as long as our seasons.For the foreseeable future, any human inhabitants of Mars would need to be comfortable living in controlled, indoor environments. At least the last year would have given them some training in this regard.

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Dr Naomi Lavelle: Is there (or could there be) life on Mars? - Irish Examiner