By Arata Yamamoto, NBC News Producer
TOKYO – Interplanetary travel using a solar-powered space yacht?
That is exactly what Japan's Aerospace Exploration Agency, JAXA, will be testing this week when it launches its H-IIA rocket from Tanegashima Island.
One of the payloads it will be sending towards Venus' orbit is a spacecraft dubbed IKAROS, for Interplanetary Kite-craft Accelerated by Radiation of the Sun, which will unfurl in space a 46 by 46 foot sail equipped with razor-thin solar cells.
Utilizing the force generated by photons, or sunlight particles bouncing off of its sail, IKAROS will propel through space, navigating its course solely by adjusting the angle of its massive canvas relative to the sun.
Or to put it more simply, if yacht sailing takes advantage of the wind to navigate its direction, in much the same way, IKAROS will be remotely controlled from Earth to align its sail to take advantage of the sun's power.
|VIDEO: Japan to launch solar space yacht|
Dr. Yuichi Tsuda, a scientist with JAXA, explained why they developed the project. "The United States has already launched several space explorers to Jupiter [and] Saturn, but all of these spacecrafts utilize radio-thermal generators. That's atomic power to generate electricity. So what we want to realize is an alternative way to reach the outer planets. That's why we are pursuing this technology, just using the energy of the sun."
Several nations, including the U.S., have tested solar sails but all within Earth's orbit and never to the point of space travel.
One of the main challenges will be unfolding the delicate sail in outer space; it has a thickness of just 7.5 micrometers or about one-tenth the thickness of a human hair.
The deployment will begin about a week after launch when the spacecraft starts rotating at a speed of 25 rpm, releasing the four weighted-latches that are attached to the sail. Using only the centrifugal force of the spin, over the course of several weeks, the canvas will unwrap itself until the entire tarp is fully extended.
If all goes well, in three weeks time, cameras attached to the spacecraft documenting the deployment will begin sending images back to earth.
It has taken JAXA $14 million and two and a half years to develop IKAROS. But if the mission proves to be successful, this may provide a new, more efficient means of space expedition. "In this way we can reduce launch cost, because we do not need a massive launch vehicle," said Tsuda.
Depending on how IKAROS performs, the next goal for the agency will be to develop a sail 10 times larger to navigate towards Jupiter, furnished with more sophisticated research and sampling equipment.
They will still need to improve and modify their flexible solar cell technology to take maximum advantage of the sun as more distant travel will mean weaker energy from the sun.
But Tsuda welcomes the challenge. "In the actual story, as you know Icarus reaches the sun and falls into the sun. But in this IKAROS project, we do not want to do that. We just want the determination and the will of the Icarus story."