NASA says we can't terraform Mars. Elon Musk disagrees.

Doyle Rice | USA TODAY

Show Caption Hide Caption Here are the finalists of NASA's Mars habitat competition The designs for 3D-printed habitats could one day be humble abodes on Mars. The final teams must now build their designs to see if they'd actually work.

Forget about that vacation home on Mars, at least for now.

NASA says there isn't enough carbon dioxide on Mars to terraform the planet, according to a study released Monday. But Elon Musk disagrees, saying there's plenty available.

Terraforming is the hypothetical process of changing a planet’s conditions in order to make it habitable for Earth’s plants and animals, including humans. The most promising candidate for terraforming is Mars, according to NASA.

In the past, scientists have theorized that carbon dioxide (CO2) and other greenhouse gases stored in Mars’s rocks and polar ice caps could be released back into the atmosphere to make it thicker, heat the planet and allow liquid water to remain on the surface.

But the study, published Monday in the peer-reviewed British journal Nature Astronomy, threw cold water on that idea.

"Our results suggest that there is not enough CO2 remaining on Mars to provide significant greenhouse warming were the gas to be put into the atmosphere," said study lead author Bruce Jakosky of the University of Colorado. "In addition, most of the CO2 gas is not accessible and could not be readily mobilized. As a result, terraforming Mars is not possible using present-day technology."

More: Water detected on Mars, raising the possibility of finding life on Red Planet

Although the current Martian atmosphere itself consists mostly of carbon dioxide, it is far too thin and cold to support liquid water, an essential ingredient for life.

At best, the authors conclude, the readily accessible carbon dioxide could only triple Mars’s atmospheric pressure — one-fiftieth of the change needed to make Mars habitable.

However, in a tweet, Tesla founder Elon Musk said that "there’s a massive amount of CO2 on Mars adsorbed into soil that’d be released upon heating. With enough energy via artificial or natural (sun) fusion, you can terraform almost any large, rocky body."

In the study, NASA examined how much carbon dioxide the planet's soil and minerals contain, but still found the amount released would be far too small to terraform the planet to the degree needed to support life.

"Terraforming Mars using the planet’s known CO2 will thus need technologies well beyond our current grasp. Any such efforts have to be very far into the future," the study concluded.