Planetary Society Declares LightSail Mission Successful

LightSail spacecraft with solar sail deployed. (Credit: The Planetary Society)
LightSail spacecraft with solar sail deployed. (Credit: The Planetary Society)

Pasadena, CA (June 10, 2015) — The Planetary Society, the world’s largest non-profit space interest group, today declared the LightSail test mission a success. After 19 days in orbit, the CubeSat spacecraft deployed its Mylar® solar sails in space. This marked a milestone for the mission to test LightSail’s critical functions in low-Earth orbit, a precursor to a second mission set for 2016.

Bill Nye (The Science Guy®), CEO at The Planetary Society, celebrated the landmark and stated:

“I’m very proud to say that our LightSail test mission was a success. We saw again that space is hard. It’s a test flight, and sure enough our little spacecraft tested us. I’ve got to congratulate our remarkable team. They solved some unexpected big problems up there with nothing but short radio signals sent from down here. This LightSail test taught us a lot, just as we hoped it would, and so we’re ready to do some real solar sailing with LightSail’s 2016 mission. Let me finish by reminding everyone that this mission and next year’s flight are funded entirely by our supporters and especially our members— people of Earth, who want to participate in space exploration. We’re changing the way humankind explores space. Today is a big day for The Society and for space explorers everywhere.”

A photograph taken by the spacecraft confirmed sail deployment. The photograph and an initial announcement were posted by Jason Davis, digital editor at The Planetary Society and embedded LightSail mission reporter.

“This week’s flight was an ideal test in preparation for our primary mission in 2016. We were able to validate the function of all key spacecraft systems including solar sail deployment, and along the way the team was forced to deal with a number of anomalies and setbacks,” said Doug Stetson, LightSail project manager and founder and principal partner of the Space Science and Exploration Consulting Group. “We’ve learned a tremendous amount about our spacecraft and operations plan, and we’re already preparing for what should be a spectacular flight late next year.”

David Spencer, professor of the practice at the School of Aerospace Engineering and director for the Center for Space Systems added, “This ambitious mission has been a challenge every step of the way. Throughout development and operations, our team has worked through problems, found solutions, and ultimately succeeded.”

The LightSail test spacecraft launched into orbit aboard a United Launch Alliance (ULA) Atlas V rocket from Cape Canaveral Air Force Station on May 20, 2015. The spacecraft was part of a secondary payload dubbed ULTRASat aboard the U.S. Air Force mission AFSPC-5.

Solar sailing works by using sunlight for propulsion. When solar photons strike LightSail’s reflective Mylar® sails, their momentum is transferred to the spacecraft, gradually accelerating it through space. While the push from photons is miniscule, it is continuous and unlimited. Solar sails can eventually reach greater speeds than those obtained from chemical rockets. LightSail is packaged into a small spacecraft called a CubeSat. CubeSats have made low-cost space missions a reality for universities and research groups.

The spacecraft was originally designed and built by Stellar Exploration Inc. in San Luis Obispo, California. Important flight system modifications, software, and integration and testing were provided by Pasadena California-based Ecliptic Enterprises Corporation (Ecliptic), a space avionics and sensor systems firm best known for its popular RocketCam family of video systems used on rockets and spacecraft. Boreal Space of Mountain View, California, serves as a subcontractor to Ecliptic. Mission analysis, mission operations, and ground systems were provided by the Georgia Institute of Technology and by California Polytechnic State University, San Luis Obispo, California. The LightSail program is managed for The Planetary Society by Doug Stetson, president of the Space Science and Exploration Consulting Group of Pasadena, California.

“LightSail’s test mission success is an important stepping stone toward a new class of CubeSats employing solar sailing for propulsion, said Rex Ridenoure, CEO of Ecliptic. “We’re embarking on a new era for solar system exploration using very small satellites.”

The Planetary Society’s second LightSail spacecraft is scheduled to fly in 2016. This mission will build on the results of the test flight to conduct a full demonstration of solar sailing in Earth orbit. LightSail will be packaged inside a spacecraft called Prox-1 built by students at Georgia Tech. The spacecraft duo will be launched aboard a SpaceX Falcon Heavy rocket to an orbit of about 720 kilometers (450 miles), and for about two weeks LightSail will serve as a rendezvous target for Prox-1 before LightSail conducts its primary mission.

The Planetary Society’s solar sailing involvement was started by Society co-founder Louis Friedman more than a decade ago. Co-founder Carl Sagan championed solar sailing on a famous 1976 episode of The Tonight Show with Johnny Carson.*

“This test mission has been a high-intensity, high-profile dress rehearsal,” said Jennifer Vaughn, chief operating officer for The Planetary Society. “Through the ups and downs of our LightSail test flight, our members, backers, and supporters around the world have cheered us on. LightSail is a tangible symbol of citizen participation in space exploration. Behind the simple beauty of an image of a shiny sail in space lit by the Sun is the collective effort of tens of thousands of enthusiasts who got this project built, launched, and tested. The successful test flight belongs to all of us.”

For complete coverage of the LightSail test flight, as well as the second LightSail mission scheduled for 2016, visit

Citizens around the world can be part of the 2016 LightSail mission. The “Selfies to Space” feature invites people to submit photographs for inclusion aboard the spacecraft:

Dr. Neil deGrasse Tyson, a member of The Planetary Society board of directors, joined Nye to launch a LightSail Kickstarter campaign in a video announcement, which led to immediate worldwide response: Funded entirely by private citizens, LightSail is the yield of collective support:

For in-depth coverage of LightSail’s test and 2016 missions, follow embedded reporter, Jason Davis at

  • Michael Grigoni

    The photos on the blog site seem to show a partially-deployed sail, e.g. it has a parabolic shape. Is this a matter of the optics and perspective? Is the sail fully deployed and planar?

  • James

    I think its the optics.

  • ThomasLMatula

    If the sail is deployed it should be reflecting a lot of light and be fairly bright. Any info on where to look for it?

  • Sam Moore

    They’ve not been put under full tension, hence the wrinkled surface; but mostly the optics.

  • Aerospike

    I think it is too small to see without a telescope, but for spacecraft tracking I always recommend
    pick your location (you don’t have to register unless you want to save your locations), and klick on lightsail on the main page.

    I’ve read that with the sails deployed, it will reenter very soon, so you’d better be quick!

  • therealdmt

    Judging from comments on the earlier topic “Lightsail Falls Silent, Battery Problem Suspected”, I guess one or two Parabolic Arc-ers are bummin’ over this success.

  • Chief Galen Tyrol

    I’ve never cheered or hoped for failure, but I still have mixed feelings about The Planetary Society.

  • Chief Galen Tyrol

    After reading this press release, I’m left wondering what exactly The Planetary society contributed to this effort. It seems that they did the fundraising and donated some of their celebrity personas, but contributed little to the technical side of things. Anyway, it takes all kinds of kinds.

    Congratulations to all involved!

  • ThomasLMatula

    Still you would think this would be something the Planetary Society would have on their webpage as it is in easy reach of small telescopes and binoculars. But then they have seen to have a real condescending towards amateur astronomers.This recent statement by one their spokespersons is a good example.

    ” One picture that’s been posted to the discussion forum appears to show a dark streak dividing bright areas on Pluto’s disk. Icelandic imaging whiz Björn Jónsson says it looks like an honest-to-goodness surface feature, and may hint at activity on the surface.

    “Dark lines crisscrossing a disk! It’s the discovery of canali on Pluto!” the Planetary Society’s Emily Lakdawalla half-jokingly observed. “We have reached Schiaparelli-quality mapping of Pluto’s surface!”

    Lakdawalla said it’s fitting that the first observations of Pluto’s surface evoke enigmas from the early days of the exploration of Mars and Venus. “Fortunately, we need only wait a few weeks more to learn whether the line is an artifact built by an alien civilization to transport valuable liquids across the Plutonian surface — or if it’s something else entirely,” she wrote.”

    Really, rather than praise the work of an amateur astronomer she went out of her way to make fun of him. Björn Jónsson never said the line was straight or artificial, merely stated something dark appears between two light areas. Perhaps a great valley like Valles Marineris caused by tidal stress from its large moon? That is why I quit the Planetary Society many many years ago.

  • therealdmt

    Why is that?