Separation Camera Takes Full Images and ‘Movie’ of IKAROS Solar Sail


Two small “separation cameras” were ejected from JAXA’s (Japan Aerospace Exploration Agency) IKAROS solar sail, which successfully took some amazing full images of the fully deployed sail. The cameras are quite small, cylindrical in shape about 6 cm in diameter and height. They were ejected from the sail using a spring, and then they looked back at IKAROS, and relayed the images wirelessly. The cameras are now floating off into space, having done their job of taking these images. Below, an animation, or movie made by combining several images.

An animation created from several pictures taken by the DCAM2 on IKAROS. The camera rotated as it was ejected from the solar sail, so it is rotating, not IKAROS. Credit: JAXA

From the JAXA press release:

We will measure and observe the power generation status of the thin film solar cells, accelerate the satellite by photon pressure, and verify the orbit control through that acceleration. Through these activities, we will ultimately aim at acquiring navigation technology through the solar sail.

So, now that we know the sail is fully deployed, next comes the big test of whether solar sailing will actually work. This is huge, to finally have the opportunity to test a solar sail in space.

Close-up of the middle of the IKAROS solar sail, taken by the DCAM2. Credit: JAXA

From the IKAROS blog, speaking as the cameras:

Unfortunately I only have the battery, and…working time is very short for about 15 minutes after I do my best work is a planets around the Sun, the world’s smallest man-made flying with IKAROS continue.

Translation: these tiny cameras only had about 15 minutes to do their job of taking pictures before becoming dead little satellites orbiting around the sun.

IKAROS was launched on May 21, 2010 from the Tanegashima Space Center in Japan.

We’ll keep you posted as JAXA begins testing the solar sail.

IKAROS graphic of how the sail deployed. Credit: JAXA

Japanese Solar Sail Deploys Successfully


New images and data from the IKAROS solar sail show the thin solar film has deployed and expanded successfully and is now generating power. Since its launch on May 21, 2010, teams from the Japan Aerospace Exploration Agency (JAXA), have been painstakingly checking out all the systems on IKAROS before deploying the sail, and even the process of unfurling the sail had been a slow process. JAXA began to deploy the sail on June 3, analyzing each step before proceeding. Yesterday, JAXA released a photo of a partially deployed sail (below), but didn’t offer much information as far as the status. But they now have confirmed that the sail was successfully expanded and is generating power. IKAROS is now about 7.7 million km from Earth.

In the image above, the harness is an electrical connection between the membrane and the main body, and the tether is the mechanical connection between the membrane and the main body.

And now comes the big test of the solar sail: will it provide the ability to navigate the spacecraft?

“We will measure and observe the power generation status of the thin film solar cells, accelerate the satellite by photon pressure, and verify the orbit control through that acceleration,” JAXA said in a press release. “Through these activities, we will ultimately aim at acquiring navigation technology through the solar sail.”

The craft will head towards Venus, and the exciting part will be finding out how fast and accurate the solar sail can fly.

Partial deploy of IKAROS, the first stage. Credit: JAXA

From the IKAROS blog (translated from Japanese):

First, the spin rate and learned that he had first IKAROS have successfully deployed from the attitude data. Then, I was part of the downlink data captured with the camera image monitor confirmed that the sail has been deployed from the image. On June 10 has been expanded to clean the sail, “stretched states” get the picture, confirmed the successful deployment of the sail after deployment finished the second check.

Also check the power of solar cells was carried out together, we achieved minimum success!

Power will be realized with the world’s first solar powered sail development.

Graphic showing the sail in full deployment. Credit: JAXA

See the IKAROS webpage for more info and detailed graphics.

Sources: JAXA, IKAROS blog

Planetary Society to Launch Three Separate Solar Sails

On the 75th anniversary of astronomer Carl Sagan’s birth, the Planetary Society announced their plans to sail a spacecraft on sunlight alone by the end of 2010. Called LightSail, the project will launch three separate spacecraft over the course of several years, beginning with LightSail-1, which will demonstrate that sunlight alone can propel a spacecraft in Earth orbit. LightSails 2 and 3, will travel farther into space.

Sagan, co-founder of the Planetary Society was a long-time advocate of solar sailing.

LightSail-1 Prior to Sail Deployment Credit: Planetary Society
LightSail-1 Prior to Sail Deployment Credit: Planetary Society

Lightsail-1 will fit into a volume of just three liters before the sails unfurl to fly on sunlight.

On today’s 365 Days of Astronomy podcast, Sagan’s widow and collaborator, Ann Druyan said this project is a “Wright Brothers Kitty Hawk-type” enterprise of inventing and proving a new way of moving through the cosmos.

“On one episode of Cosmos, we wrote ‘We have lingered too long on the shores of the cosmic ocean. It’s time to set sail for the stars,'” she said. “And that’s what I was thinking when it became clear that we had the resources to mount this expedition, that we are serious at The Planetary Society. And at Cosmos Studios, my company which provided the principal support for the first 10 years of this project, we’re really serious about giving our kids a future in which science and technology is used in its most wise and benign and forward-looking possible way. That’s why I’m so thrilled and I just think if Carl were alive he would have been absolutely overcome at the notion that The Planetary Society is mounting its own space program, let alone its own launch.”

The solar sail project was boosted by a one-million-dollar anonymous donation.

Taking advantage of the technological advances in micro- and nano-spacecraft over the past five years, The Planetary Society will build LightSail-1 with three Cubesat spacecraft. One Cubesat will form the central electronics and control module, and two additional Cubesats will house the solar sail module. Cameras, additional sensors, and a control system will be added to the basic Cubesat electronics bus.

Reflected light pressure, not the solar wind, propels solar sails. The push of photons against a mirror-bright surface can continuously change orbital energy and spacecraft velocity. LightSail-1 will have four triangular sails, arranged in a diamond shape resembling a giant kite. Constructed of 32 square meters of mylar, LightSail-1 will be placed in an orbit over 800 kilometers above Earth, high enough to escape the drag of Earth’s uppermost atmosphere. At that altitude the spacecraft will be subject only to the force of gravity keeping it in orbit and the pressure of sunlight on its sails increasing the orbital energy.

Lightsail-2 will demonstrate a longer duration flight to higher Earth orbits. LightSail-3 will go to the Sun-Earth Libration Point, L1, where solar sails could be permanently placed as solar weather stations, monitoring the geomagnetic storms from the Sun that potentially endanger electrical grids and satellite systems around Earth.

The Planetary Society’s attempt in 2005 to launch the world’s first solar sail, Cosmos 1, was scuttled when its launch vehicle, a Russian Volna rocket, failed to reach Earth orbit.

For more information, see the Planetary Society’s LightSail Page.