June 3, 2010

On IKAROS and Interplanetary/Interstellar Kites

I love kites. I have three stunt kites among others which I sometimes fly on summer weekends at the park near Liberty Science Center (overlooking New York City) where the constant breeze is best for kite-flying around the area. To this day, I am still amazed how the wind translates to flight.
As a child growing up in the Philippines, I often ran in the streets with a kite I made out of newspapers and "walis tingting". As I pulled on the string (which i stole from my grandmother's sewing kit), I wondered how high and how far my kites could go. I remember myself asking if they could go past the clouds, the blue sky, and out beyond the unknown expanse.
The answer came many years later, but its so much better than it could ever be.
On May 20, 2010, an interplanetary kite has been launched that will fly to another world. The IKAROS will go to Venus and beyond.
The IKAROS (Interplanetary Kite-craft Accelerated by Radiation Of the Sun) is a solar sail mission powered solely by sunlight. A solar sail is pushed by the photons from the Sun. In other words, it uses sunlight to sail.
When a photon is reflected it exerts a small force on the surface reflecting it. The Sun generates a lot of photons, so if you have a large, lightweight, reflective surface, it will be pushed by the force of many photons being reflected off it. It is the reflected photons that creates the "pushing" effect.
The solar sail hitched a ride aboard an H-2A rocket from Japan's Tanegashima Space Center. That rocket carries the main mission of the Japan Aerospace Exploration Agency (JAXA), the Venus Climate Orbiter called Akatsuki.
IKAROS is the first of it's kind to ever be launched and I hope it will work because it's success will pave the way for future solar sail missions that may even extend past our Sun into other stars. Thus, I have whimsically labeled a future acronym for it's successor: Interplanetary Kite ARound Other Stars (IKAROS).
I am very excited about IKAROS so I watched it's launch on a live feed. Perhaps watching its launch was related to the fact that launching my jetstream kite from the ground is also my favorite part.
My kite is initially in a launch position, facing the wind, facing me, and pointing up. I wait for a suitable gust of wind to pass through my back and reach the kite. At the right moment, I pull both strings and step backwards, I can feel the strength of the wind as I watch the kite accelerate upwards. For me, it is the most exhilarating part of flying kites. I advise you to try it.
By the way, did I mention that "Exoplanetology" is actually riding the IKAROS? Yes, a few months back I actually filled up a form at The Planetary Society's website to send a message to be carried along with IKAROS. Unfortunately, it wasn't encoded in the certificate of participation that was provided, but my message was "Interplanetary Now, Exoplanetary Next".
I hope that this short message encourages others in the hope that one day, we will have a probe exploring another solar system, and most importantly--an extrasolar planet!

Links:
Light Sail: Solar Sail from Planetary Society
From Centauri Dreams: http://www.centauri-dreams.org/?p=12588