Mars is the most Earth-like planet in our solar system. It’s rocky, it’s not too big or too small and its temperature isn’t that far off from what we experience here on Earth, relative to the rest of the planets in our neighborhood. There’s still one big problem that would make life difficult for a human settlement on Mars and that is its lack of atmosphere.

A very thin atmosphere still exists around the planet, but it’s less than 1 percent as dense as ours on Earth. One way to give the atmosphere a boost is by releasing more CO2, and scientists know that there’s some of that trapped in Martian ice and rock. Unfortunately, a new study has just revealed that one of the more, uh, interesting ways of unlocking that CO2 will probably not do us any good.

One of the proposed methods of pumping more CO2 into the red planet’s atmosphere is by bombing the planet’s poles. This would certainly release some more CO2 that is trapped in the ice caps on the planet’s poles, but new research published in Nature Astronomy reveals that the amount of CO2 it would release wouldn’t be nearly enough to increase the planet’s atmospheric pressure to an acceptable level.

According to the researchers, if we managed to release all the CO2 from the planet’s ice caps it would only increase the atmosphere to around 1.2 percent that of Earth. Furthermore, if mankind somehow invented a way to squeeze the CO2 from all the material on Mars (that’s essentially impossible), it would only boost the atmosphere to around 6.9 percent of Earth’s.

Terraforming — that is, making an inhospitable planet comfortable enough that humans could settle on it without living in domes — is a concept that was popularized long ago by science fiction and while we might some day have a system for turning planets like Mars into more Earth-like homes for humanity, that’s still a long ways off.

NASA’s tentative plans are to have a manned mission headed to Mars by sometime in the 2030s, but growing budget concerns and delays in the development of the spacecraft that are supposed to send astronauts to the red planet are making that timeline look more and more unrealistic.