A week after LightSail deployed it solar sail, the experimental spacecraft fell from orbit and disintegrated in the Earth's atmosphere. It was expected to have disintegrated on Sunday around 1:23 p.m. EDT.

The Planetary Society CEO and Science Guy Bill Nye was delighted to have seen it pass through the sky.

"Tonight, for the first time, I glimpsed our spacecraft with my own eyes. It was just the faintest pinprick against the bright lights of the big city. But, there it was right on time and exactly per the coordinates," Nye writes in a blog, which was first published on LightSail's Kickstarter page.

"My few moments alone on the roof tonight with our LightSail spacecraft silently crossing the sky were very gratifying," he added.

The people behind the LightSail said they have accomplished the project's mission - testing the deployment of the spacecraft's sails. The experimental solar sail spacecraft was able to deploy about 90 percent of its 32-square-meter panels, which were made of plastic, more than two weeks since LightSail was launched.

"It is conceivable that we could run the motor a few more counts and stretch the sail out more," project manager Doug Stetson said, according to NBC News.

Although the spacecraft experienced several communication glitches, it was able to receive and execute the deployment command on June 7. Two days after deployment, LightSail took a "selfie," displaying sails that were almost completely spread out.

The initial test mission will be followed by the launch of LightSail-B in 2016. LightSail-B is hoped to give more proof that solar sailing can be an economial way to send small spacecraft in space.

"We are advancing space science and exploration," Nye said in his blog. "This mission is part of our mission. The best is yet ahead."