On May 20, Bill Nye the Science Guy and his colleagues at The Planetary Society launched their first real test of LightSail, a sail that uses the momentum of the sun's energy as a physical force to push spacecrafts along. But then it lost contact with Earth -- for eight days. On Saturday, LightSail got back in touch. Its computer isn't working perfectly, but a daily reboot should keep it on task. Now representatives from The Planetary Society say it could be deployed as early as Tuesday.

The sail, which is similar to tech described in retro sci-fi and was pitched repeatedly by Carl Sagan during his day, works like this:

The mylar sail, which is about as big as a boxing ring and thinner than a human hair, is solar-powered -- but it's not a solar panel. It's a sail just like one you'd find on a boat, but it uses the natural momentum of the sun's photons instead of the push of wind. The force is small, but continuous. "With a chemical rocket, there's a big boom, a phwooosh, the ground shakes, but then nine minutes later you're done and you're coasting all the way to Pluto," Nye told The Post back in January. "With these kind of sails, the propulsion doesn't just stop. It's on day and night -- except wait, there's no night!"

[Bill Nye: Climate change is “not something you should be debating or denying”]

Because the sail is so delicate, deploying it is easier said than done. That's the purpose of the current mission: The sail and the tiny CubeSat it's attached to won't be doing anything fancy this time around, but hopefully Nye and the rest of his team will see that it's possible for the sail to unfurl without a hitch. Or without any more hitches, anyway.

In 2016, the group will launch a full mission. The Kickstarter campaign to fund that trip has already surpassed its $200,000 goal (in fact, it's at over $790,000 with 25 days more to go) so if LightSail can manage to deploy, all systems are go.

But wait: You were promised a video of The Science Guy surfing. And here it is:

Nye and his team shot the video to celebrate LightSail's successful launch, but by the time they emailed me an embargoed clip (yes, I get embargoed clips of Bill Nye surfing, aren't you jealous) LightSail was incommunicado, so it was kind of a bummer. When things took a turn for the better, Nye had the video released early to celebrate.

Enjoy Bill Nye the Surfing Guy, and hopefully we'll have another LightSail update soon.

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