Comets headed for Mars

Terraforming Mars A Non-Starter: Need 10 Million Comets Made Of Pure Carbon Dioxide

A leading scientist on NASA’s MAVEN mission has asserted that terraforming the planet Mars is a future scenario that is simply unfeasible. In fact, transforming the red planet into a greener, Earth-like world would require an enormous amount of carbon dioxide, a gas that, though thought to be at one time quite prevalent on the planet, today is in scant supply. So for Mars to be terraformed, it would need a CO2 infusion — one on an astronomical scale.

Bruce Jakosky, the principal investigator for NASA and MAVEN (Mars Atmosphere and Volatile EvolutioN) spacecraft mission, says that current levels of CO2 on Mars would not be nearly enough for a transformative project like terraforming the red planet. And, unfortunately, Mars is in the process of gradually losing its atmosphere. The MAVEN mission itself was undertaken to collect data on the depletion of said Martian atmosphere and they have found that the depletion rate of CO2 is quite low and will take eons to dissipate.

“The rate of loss of gas today is very low — slow enough that it would take billions of years to remove the equivalent amount of gas that is in the atmosphere,” Jakosky told Seeker via email.

However, the level of carbon dioxide currently in the Mars’ atmosphere and in the planetary environment is not enough to provide the necessary amounts that would be required to terraform the planet.

“There isn’t a source of CO2 that could replenish the atmosphere — even outgassing of CO2 from volcanoes has got to be incredibly slow today,” Jakosky said. “If we wanted to put enough CO2 into the atmosphere to raise temperatures significantly, it would take something like 10 million kilometer-sized comets (if they were all made entirely of CO2). This is just not feasible.”

MAVEN analyzed the data showing the loss of argon-36 and argon-38, which gave scientists a better picture of the loss of carbon dioxide from the Martian atmosphere. As explained by Seeker, “argon is removed by only one process: sputtering, which occurs when charged particles (ions) in space are picked up the solar wind because they have an electrical charge. Some ions accelerate into the Martian atmosphere and knock molecules into space, including argon and CO2.”

This analysis indicated that roughly two-thirds of all the argon that was ever in the Martian atmosphere has been lost to space through sputtering. The researchers were able to conclude that an even greater amount of CO2 was lost due to it being able to become lost through other processes.

“In total, this means that the majority of gas in the atmosphere has been lost to space,” Jakosky said.

a plant grows on Mars
Current data on Mars indicates that the amount of carbon dioxide on the planet is far too little to achieve terraforming. [Image by Lia Koltyrina/Shutterstock]

And so go the dreams of there ever being a green Mars. Unless, of course, you count alien technology. Seeker writer Elizabeth Howell points out that terraforming alien worlds is accomplished in the new video game Mass Effect: Andromeda in just this manner — alien technology.

But since alien technology capable of transforming even the most inhospitable worlds into habitable planets has yet to be made available to non-denizens of the Mass Effect universe, we are left with what is available, or at least hypothetically so. Except that comets made of pure carbon dioxide have yet to be discovered, let alone 10 million of them. And humans as yet do not have the capability of harnessing comets and directing them in a coordinated combined bombardment of a planetary object.

stages of terraforming Mars
Artist’s depiction of the terraforming of Mars. [Image by manjik/Shutterstock]

So, for all those dreamers of a green Mars — like fans of the award-winning Mars Trilogy by Kim Stanley Robinson, where his cast of characters terraform Mars into not only a verdant world in two centuries, but also a planet that supports a working water cycle — it looks as if terraforming the red planet into an Earth surrogate or twin is more of a hopeful fantasy than it is hard science or even realistic science fiction.

[Featured Image by Aphelleon/Shutterstock]