Spotted garden eels live in colonies of up to several thousand individuals. They spend the majority of their lives with only the top half of their body sticking out of a burrow they make in the sand, eating plankton and other tiny animals that float by. If in danger, the entire “garden” retracts into the sand in the blink of an eye.

Images: blueparadiseindonesia, Eric Cheng, Ryan Murphy

When Are We Going to Finally Colonize Space?

The Earth is doomed, and the only question is how long humanity has left. Fortunately, we have options: in the past few years there’s been a flurry of potentially habitable planets discovered. In June, German astronomers found three planets relatively near to us that orbit around a star at a distance that suggests they could have liquid water—and therefore life. To learn more about our future on other planets, we talked to Daniel Berleant, a scientist who earlier this year published The Human Race to the Future, a book about the final fate of humanity.

When I was young, we hadn’t detected any planets outside the solar system that could be habitable, and the thinking was there probably weren’t very many. That’s part of this kind of human-centric viewpoint that we’ve had for a long time. We used to think that the sun revolved around the Earth and then we discovered that we revolved around the sun—then they thought that the Earth was probably the only habitable planet around, and we’re discovering that’s not the case. 

It’s good for us to think about settling humanity on other planets because if something goes wrong—terribly wrong—on Earth, we’ve hedged our bets. If the sun exploded or something, if there were human colonies on distant planets, we would survive. The more extraterrestrial bodies we’re inhabiting, the better. 

Having said that, of course it’s going to be a lot easier to colonize, like, the moon or Mars. Traveling outside the solar system gets to be a little trickier. The planets they’ve just discovered are 22 light years away, which doesn’t sound like a big number, but really, it’s very far away [about 129 trillion miles]. We don’t know how to build ships yet that would go fast enough to get people there in a reasonable time. One of the positive things about really fast travel—as in travel near the speed of light—is that time on the spaceships would go slower. So although it might take 22 or many more years of Earth-time to get there, subjectively on the spaceship, it could take less.