Purchasing new hardware? Read our latest product comparisons

NASA to fly largest solar sail ever, in 2014


February 5, 2013

The 20-meter (65.6-ft) solar sail and boom system, developed by L'Garde Inc. of Tustin, California (Image: NASA)

The 20-meter (65.6-ft) solar sail and boom system, developed by L'Garde Inc. of Tustin, California (Image: NASA)

Image Gallery (2 images)

NASA is getting ready to ride the “winds” of space on sails lighter than gossamer, yet large enough to cover a small field. The space agency’s Solar Sail Demonstration, also known as the Sunjammer Project, may launch as early as 2014 when it will send the largest solar sail yet built into orbit, to demonstrate the technical viability of the device.

Sunjammer and the term “solar sailing” were coined by Sir Arthur C. Clarke in his 1964 short story, The Sunjammer. It’s an idea that goes back to Johannes Kepler, though it was James Clerk Maxwell whose theory of electromagnetic fields and radiation showed that a sail could be pushed by sunlight.

It’s an unbelievably tiny push, so the payload must be very small and the sails very large and light, but over time it can really add up. A typical spacecraft on the way to Mars can be pushed as much as 1,000 kilometers during the journey even without solar sails. NASA’s Messenger probe, for example, used its solar panels as sails for making course corrections.

The basic design of a solar sailing spacecraft is an ultralight mirrored Mylar sail controlled by spider thread-like lanyards, that is propelled by the pressure of light from the sun. The term solar sailing is apt because the principle is exactly the same as with nautical sailing, with the same maneuvers of tacking, luffing and running before the "wind." The hard part is coming up with a design that is light enough to be pushed by sunlight, yet that can maintain its shape without collapsing, so solar sails tend to be either web-like affairs or spun to keep their shape through centrifugal force.

In Sir Arthur’s short story, the solar sails were used to propel manned space yachts in a race around the Moon. NASA is much less ambitious. The Sunjammer’s "In-Space Demonstration of a Mission-Capable Solar Sail" is intended simply to test the feasibility of solar sails, and the design of the unmanned craft reflects this. It’s seven times larger and weighs ten times less than previous solar sails. Measuring approximately 124 feet (38 m) on a side, it covers almost 13,000 square feet (1207 m²) or a third of an acre. Despite this, it weighs only 70 pounds (32 kg) and collapses to the size of a dishwasher. It uses vanes for attitude control, and the total force that it’s designed to deal with is only about 0.01 newton – or around the weight of a packet of artificial sweetener.

Sunjammer is being built by L'Garde Inc. of Tustin, California in association with the National Oceanic and Atmospheric Administration. Its design advances on 2005-2006 vacuum chamber ground tests by L’Garde at NASA’s Plum Brook Facility in Sandusky, Ohio, and the deployment of the 100-square foot (9.2 m²) NanoSail-D sail in Earth orbit in early 2011.

The Sunjammer will go into Earth orbit as a secondary payload on a Falcon 9 rocket. Once in orbit, the Sunjammer will unfurl its sail and then it will go through its paces as the attitude controls, sail stability and trim are tested and a navigation sequence is executed.

According to NASA, the Sunjammer technology is suitable for a wide range of missions including deployment of space weather systems to warn satellites of solar storms, and as a means of cleaning up space debris, hovering at high altitudes, and propelling deep space missions.

Source: NASA via Dvice

About the Author
David Szondy David Szondy is a freelance writer based in Monroe, Washington. An award-winning playwright, he has contributed to Charged and iQ magazine and is the author of the website Tales of Future Past. All articles by David Szondy

Ok I give up, how do you tack without a keel and something for it to push against ?


I remember seeing Echo, a giant orbiting mylar balloon, crossing the skies. This should be pretty easy to spot.

John Hagen-Brenner

I can see this type of craft being more useful towards the sun than away from it. square of the distance from the light source should reflect the power? could they also be used to cool the Earth by sending a bunch of them towards the sun? climate control ! wasn't this sort of thing also in a sci-fi story? only i think it was controlling sunspots to contol the weather down to towns and countries, not the whole planet.


How can something be ten times less? If it's one times less, it's zero. What's wrong with using clear english? Is it that hard to understand that it's one-tenth the weight?


"Ok I give up, how do you tack without a keel and something for it to push against ?"

The keel on a boat is there mosly to keep the boat from capsizing when the wind pushes on the sail. You don't have to worry about that in space because the medium you are navigating through is all around the vessel instead of just beneath the vessel.

The steering mechanisms I've read about for solar sails involved methods of changing the reflectivity of the sail so that pressure on the sail is uneven.


The thing kinda reminds me of Iclarus in James Bond's Die Another Day...


Roma Khudoleyev

nicho the "vessel" is pushing against the earth's gravity to stay in orbit. BTW boats that can sail upwind effectively are a relatively recent invention.

Post a Comment

Login with your Gizmag account:

Related Articles
Looking for something? Search our articles