Dropping Oxygen

For now, life is flourishing on our oxygen-rich planet, but Earth wasn't always that way – and scientists have predicted that, in the future, the atmosphere will revert back to one that's rich in methane and low in oxygen.

This probably won't happen for another billion years or so. But when the change comes, it's going to happen fairly rapidly, the study from earlier this year suggests.

This shift will take the planet back to something like the state it was in before what's known as the Great Oxidation Event (GOE) around 2.4 billion years ago.

What's more, the researchers behind the new study say that atmospheric oxygen is unlikely to be a permanent feature of habitable worlds in general, which has implications for our efforts to detect signs of life further out in the Universe.

"The model projects that a deoxygenation of the atmosphere, with atmospheric O2 dropping sharply to levels reminiscent of the Archaean Earth, will most probably be triggered before the inception of moist greenhouse conditions in Earth's climate system and before the extensive loss of surface water from the atmosphere," wrote the researchers in their published paper.

At that point it'll be the end of the road for human beings and most other life forms that rely on oxygen to get through the day, so let's hope we figure out how to get off the planet at some point within the next billion years.  READ MORE...