Can You Fly Using Only Light?

You bet you can!

The Japanese space agency (JAXA) recently launched a test vehicle for solar sail technology called IKAROS. (Read about it here in a previous post)

IKAROS. Photo: JAXA

The solar sail was unfurled and, a few days ago, JAXA confirmed that IKAROS was indeed accelerating!

Due to the pressure light from the sun striking the solar sail, IKAROS is accelerating at 0.00000356 meters per second per second.

For comparison, if you were to drop a cup in the kitchen, it will accelerate toward the floor at 9.8 meters per second per second. Pretty fast. Thats about 2,750,000 times faster than IKAROS is accelerating now.

So, how could IKAROS possibly be useful? Well take into account that the cup only accelerates toward the floor for about a tenth of a second or so before it shatters in a brilliant display.

IKAROS, on the other hand, is constantly accelerating. And it will continue to accelerate as there is nothing in space to stop it.

So if IKAROS were to accelerate at the same rate for the next year, it will end up moving at a speed of over 100 meters per second and would have travelled over 1,770,000 km.

All without using a drop of fuel!

And IKAROS is just a test vehicle. Further iterations of the design will involve bigger and more efficient sails, resulting in bigger accelerations.

I firmly believe that the first generation of deep space explorers will be using solar sail technology to get where they are going.

Exciting stuff people!