Bill Nye celebrates solar sail deployment by LightSail spacecraft

Bill Nye the science guy is a happy guy now – a solar sailing spacecraft launched by his non-profit organization has unfurled its solar sail after two challenging weeks in space.

The LightSail spacecraft deployed its solar sail on Sunday afternoon, drawing claps and cheers from the team at the Planetary Society, the non-profit organization behind the project.

"Oh my goodness… that's so cool," said Nye, the group's CEO in a video posted on YouTube. "This is a big day for the Planetary Society. We're advancing space science and exploration."

The group, co-founded by astronomer Carl Sagan, has been working for more than a decade to launch a spacecraft powered by solar sails – ultra-thin sheets of mirrored surfaces designed to capture the momentum from solar energy photons.  The small, continuous acceleration allows a spacecraft propelled by solar sails to reach high speeds over time without any fuel.

The group's first attempt to launch a solar sailing spacecraft in 1995, which would have been the first in the world, failed after the spacecraft didn't make it into orbit.

The current attempt launched on May 20. Just two days later the LightSail spacecraft lost contact with ground crews due to a software bug. After eight days of silence, the spacecraft rebooted and contact was restored. The spacecraft went silent again Friday, shortly after its solar panels were deployed, but got back in contact Saturday.

A first attempt to deploy the solar sails on Sunday didn't work, but things seemed to go well on the second orbit, Nye reported.

"Although the spacecraft has been in inertial space, I feel as though I've been on a roller coaster," he added.

You may be able to spot LightSail

The glint from the spacecraft's solar sails  is expected to be visible from the ground. The Planetary Society has a webpage that allows people to track the spacecraft relative to their location.

"Look for flyovers that occur around dawn and dusk," advised Jason Davis, the Planetary Society's digital editor, in a blog post. "The best time to see any spacecraft—including LightSail—is when you are standing in Earth's shadow but the spacecraft is still illuminated by sunlight."

The spacecraft is not expected to be in space for long – it's not in a high enough orbit to escape Earth's atmospheric drag, which is substantial now that the sails are deployed. That will cause its orbit to decay quickly in the coming days.

The current test flight is designed to gather data for next year's flight in a higher orbit. The Planetary Society has a crowdfunding campaign to raise money for that mission.