‘Lost in Space': How Far Away Is Alpha Centauri, and Could Humans Live There?

Colonists from Earth are heading to the nearest star system to Earth in Netflix’s series, but “nearest” is still extremely far away

(Note: This post contains light spoilers for Netflix’s “Lost in Space.”)

Humans are looking to colonize the rest of the universe in Netflix’s reimagining of the 1960s sci-fi TV show “Lost in Space.” Of course, it doesn’t go very well — hence the name of the show.

When viewers catch up with the Robinson family at the start of the series, they’ve crashed onto an unfamiliar alien planet nobody knew was there. But it also wasn’t their actual destination. The Robinson family is one of many aboard a huge ship known as the Resolute, which is venturing to Alpha Centauri star system. It’s the closest to Earth, and the plan is to continue building a colony on one of the planets there.

It seems by the time we’re with the Robinsons on the show, the Alpha Centauri colony is already fairly well established, and multiple trips have been made there by humans. So what exactly is Alpha Centauri, and how far away is it?

Alpha Centauri is a system of three stars and the planets that revolve around them. There’s Alpha Centauri A and Alpha Centauri B, two stars that form a binary star system, and a smaller red dwarf star known as Proxima Centauri. The first star is brighter and a little larger than our sun; the second, smaller and cooler.

The system might consist of the closest stars to our own sun, but it’s still pretty far away: 4.37 light years, or more than 25.6 trillion miles. We don’t really have the technology yet to send humans that far, either; on a conventional rocket, traveling at about 17,600 miles per hour, it would take about 165,000 years for humans reach Alpha Centauri (and then another 4.37 years for communications to travel back at the speed of light to let Earth know they’d arrived). Proxima Centauri is a little closer than the other two stars at 4.24 light years away, making it the nearest neighbor to the sun.

Obviously, on “Lost in Space,” the Robinsons weren’t gearing up for a journey of more than 100 thousand years. The show gets around the distance by introducing some interesting technology later in the first season — although it doesn’t provide much in the way of details about how it works. But we know that the Resolute has engines that get it to the colony and back again: At one point, Maureen Robinson (Molly Parker) mentions that mechanic Don West (Ignacio Serricchio) has been to Alpha Centauri and returned as part of his job.

As for whether there would really be a planet for people to live on in orbit around Alpha Centauri? There probably would be. Alpha Centauri is an attractive candidate for the search for exoplanets because Alpha Centauri A and Alpha Centauri B are similar to our own sun. Astronomers have also discovered that Proxima Centauri has at least one rocky planet located in its “habitable zone.” That’s an orbit not unlike Earth’s, close enough to the star to keep the planet warm, but not so close that the star’s radiation scorches the planet’s surface.

Scientists are skeptical about the planet orbiting Proxima Centauri, known as Proxima Centauri b, though. Because of the smaller size and luminosity of Promixa Centauri, the chances the planet is so close that it would be tidally locked — meaning that one side always faces the star, making it perpetually day for one half the planet and perpetually night for the other — are higher. The nearer proximity to the star could also mean other problematic affects of gravity, like increased seismic activity. So while Proxima Centauri b is in the right orbit, it might not be habitable at all.

Scientists believe there could be more planets in the Alpha Centauri system and in it stars’ habitable zones, thanks to computer models. And the fact that Alpha Centauri A is a similar star to our own suggests there could be habitable planets in the system. So a colony for the Robinsons of “Lost in Space” to join isn’t too far-fetched — sci-fi writers have been suggesting it for quite a while.

As for right now, though, humanity doesn’t have much information about what planets actually exist in our neighboring solar system, and we have no way of getting there in a reasonable amount of time.