Planetary Society: LightSail-1 Solar Sail cubesat to Launch by 2016

Nine years after a rocket failure destroyed its solar-sailing spacecraft, the Planetary Society, the nonprofit space advocacy group led by scientist and popular TV host Bill Nye, is ready for another try.

On Wednesday (July 9), the Planetary Society announced launch dates for its LightSail-1 spacecraft, a possible test flight in 2015 (LightSail-A) and a full mission the next year (LightSail-B) with nearly identical hardware.

Both solar sail missions operate under the LightSail-1 designation.

LightSail-B will steer in Earth's orbit using nothing more than radiation from the sun. Made up of three miniature CubeSats, it will launch aboard SpaceX's Falcon Heavy rocket, which has yet to be flown.

The four sails will ride inside the CubeSats until they're ready to be unfurled, several weeks after liftoff.

Prox-1 cubesat developed by Georgia Instutute of Technology.

Credit: GIT

LightSail-B will be boosted to medium-Earth orbit inside another spacecraft called Prox-1, a Georgia Institute of Technology project.

Prox-1 will spit LightSail out and remain nearby to watch the spacecraft unfurl.

LightSail-A, meanwhile, would only reach low-Earth orbit in a mission designed to show how well the craft operates in space.

The sails themselves should be visible to the naked eye from Earth; they cover 344 square feet (32 square meters), Planetary Society representatives said.

LightSail-1 is a successor to the society's Cosmos 1, which failed to reach orbit aboard a Russian Volna rocket in 2005.

It ended up falling into the Barents Sea, an Arctic sea located off the northern coasts of Norway and Russia, the very location where it had launched by submarine.

The Planetary Society sees solar sailing as a vast improvement over traditional spacecraft, which require expensive fuel and engines to perform maneuvers in space. Sailcraft instead use solar radiation to increase their speed.

This is a gradual pressure that takes more time to move spacecraft, but Nye said he sees this as a more sustainable way to explore the solar system.

NASA's NanoSail-D Completes Mission: 240 days

NASA nanosatellite that deployed the agency's first-ever solar sail in low-Earth orbit has successfully completed its Earth Orbiting Mission.

The NanoSail-D, which was launched on Nov. 19, 2010 as a payload on NASA's FASTSAT, has completed more than 240 days "sailing" around the Earth to demonstrate and test the deorbiting capabilities of a large low mass high surface area sail.

"The NanoSail-D mission produced a wealth of data that will be useful in understanding how these types of passive deorbit devices react to the upper atmosphere," said Joe Casas, FASTSAT project scientist at NASA's Marshall Space Flight Center in Huntsville, Ala.

View a Flickr Slideshow of NanoSail-D

Casas added that the data collected from the mission is being evaluated in relation to data from FASTSAT science experiments which are intended to better understand the drag influences of Earth's upper atmosphere on satellite orbital re-entry.

The FASTSAT science experiments are led by NASA's Goddard Space Flight Center in Greenbelt, Md. and sponsored by the Department of Defense Space Experiments Review Board which is supported by the Department of Defense Space Test Program.

According to the space agency's initial assessment, NanoSail-D exhibited the predicted cyclical deorbit rate behavior that was only previously theorized by researchers.

"The final rate of descent depended on the nature of solar activity, the density of the atmosphere surrounding NanoSail-D and the angle of the sail to the orbital track," said Dean Alhorn, principal investigator for NanoSail-D at Marshall Space Flight Center.

"It is astounding to see how the satellite reacted to the sun's solar pressure. The recent solar flares increased the drag and brought the nanosatellite back home quickly."

Japan's JAXA to launch Venus probe and solar sail

Japan to launch Venus probe and solar sail

Japan was set to launch its first Venus probe Tuesday, using a rocket that will deploy an experimental "space yacht" propelled by solar particles bouncing off its kite-shaped sail.

The H-IIA rocket was positioned at the Tanegashima space centre in southern Japan in fair weather Monday for its lift-off the next day at 6:44 am (2144 GMT Monday), said the Japan Aerospace Exploration Agency (JAXA).

It will blast off with the "space yacht" Ikaros -- an acronym for Interplanetary Kite-craft Accelerated by Radiation of the Sun -- which moves thanks to the pressure of sunlight particles hitting its square sail.

Ikaros, which has cost 1.5 billion yen (16 million dollars) to develop, will be the first use of the technology in deep space, as past experiments have been limited to unfolding its sail in orbits around the Earth.

The experimental spacecraft's sail, thinner than a human hair, is also equipped with thin-film solar cells to generate electricity, creating what JAXA calls "a hybrid technology of electricity and pressure".

The technology could enable space travel without fuel as long as there is sunlight, its developers say.

JAXA plans to control the path of Ikaros by changing the angle at which sunlight particles bounce off the silver-coloured sail.

Ikaros will initially be a short cylindrical shape when it is released into space, when it will extend its sail, which measures 14 metres (46 feet) on each side and 20 metres diagonally.

What is Solar Sailing?

Solar sail propulsion is simple in concept. Light photons bounce onto a mirror-like aluminized Mylar sail. As each photon hits, its momentum is transmitted to the spacecraft.

Photons have no mass but lots of energy, so a solar sail space probe requires no onboard fuel. The force acts continuously, meaning a solar sail can eventually reach speeds five to ten times greater than any chemical rocket.

Russia, the U.S. and the European Space Agency all started solar sail missions and technology programs but cut them back when money got tight. Japan, we are happy to say, is now moving ahead to develop an innovative solar sail and solar-powered ion drive hybrid.

Yet solar sail propulsion remains largely neglected. That's why the Society has long championed efforts to prove its value. We partnered with Cosmos Studios on the far-sighted Cosmos 1 solar sail project. But technology has advanced enormously since then. We can do more in a fraction of the size, with a fraction of the weight and at a fraction of the cost. This has led us to re-think everything…and what we've arrived at is far more advanced, and ultimately far more valuable.

This technology also opens up many new possibilities for piggyback launching into Earth orbit, which is desperately needed since launch vehicles have been a hindrance preventing solar sail flight. We're considering several launch possibilities and will select the most reliable one that matches our schedule and final orbit choice best.