So, it’s goodbye to 2010, the Year of the Tiger, and hello to 2011, the Year of the Rabbit.
Chinese astrology is fun. Like the Western kind, you can make pretty much anything fit its predictions, which is convenient as I look back on the last 12 months in Japanese science: A year that should be regarded as triumphant, at least for Japanese space exploration.
In Chinese astrology, the tiger is supposed to represent movement, restlessness, and travel — which, happily, is perfect for my purpose. And that’s all the more so since 2010′s tiger was actually a metal one — metal being one of five “elements,” along with wood, fire, earth and water, that is associated with each year in the Chinese zodiac.
One of the year’s most exciting stories was the saga of Japan’s space probe, Hayabusa. Unfortunately, the name means “peregrine falcon,” not “tiger” — but it was in large part metallic. And if anything represented movement and travel — not to mention restlessness — it was Hayabusa.
Launched from the Kagoshima Space Center, Uchinoura, in Kyushu in 2003 by the Japan Aerospace Exploration Agency (JAXA), the spacecraft traveled 2 billion km to reach its destination — the near- Earth asteroid Itokawa (named after renowned rocket scientist Hideo Itokawa, popularly known as “Dr Rocket”). Then it became the first probe to ever land on and attempt to take samples from an asteroid.
Even after it had gathered its sample from the 500-meter-long, potato-shaped asteroid some 290 million km from Earth (as the crow flies, that is, if not the space rocket) — with which it stayed for three months in 2005, and on which it landed that November — Hayabusa had to get home safely. There were numerous problems with communication and propulsion systems that delayed its scheduled return in 2007, but JAXA scientists solved them elegantly. Then, in June 2010 — right at the end of what ended up being a 6 billion km voyage — came the most dangerous part of all: re-entry into Earth’s atmosphere.
With Hayabusa traveling at 12.2 km per second, JAXA technicians had to ensure it entered the atmosphere at a very specific point in order to land on target in the Australian Outback.
Peregrine falcons are the fastest-flying birds on Earth, but Hayabusa was traveling at interplanetary speed. It was the second-highest-velocity re-entry of any capsule in history, and it lit up the night sky in southern Australia on June 13 as it tore through the atmosphere, reaching 3,000 degrees C.
We are still waiting to see if the heroic return of Hayabusa will yield scientific data. The idea was to collect samples of material from the surface of Itokawa, but we don’t yet know for sure if the mission succeeded, though it is believed some dust particles were brought back.
Success or not, Hayabusa 2 is already being developed, at an estimated cost of ¥16.4 billion. It could launch as soon as 2014 — the Year of the Horse. Should the new probe be renamed uma (horse)?
Its predecessor was designed to collect samples that will help us both to investigate how the Earth formed, and provide insights into asteroid composition — which may help if we are threatened by an asteroid impact and Bruce Willis isn’t around to save us. However, Hayabusa 2, which will land on a kilometer-sized asteroid with the prosaic name of 1999 JU3, has a different mission. It will search for organic molecules that might have seeded life on Earth. The rock has a boring name, but the visit could more than make up for that.
Metal tiger also works as an image for another Japanese space mission, IKAROS. The acronym stands for Interplanetary Kite-craft Accelerated by Radiation Of the Sun, though to me it seems to be tempting fate to name a solar spacecraft (almost) after the myth of the man who flew too close to the sun and died. But what do I know.
Launched in May 2010, IKAROS became the first spacecraft to successfully demonstrate solar-sail technology in interplanetary space. This is sci-fi technology come to life. Solar sails generate power like solar panels, and are propelled by the pressure of sunlight alone. This means that in theory they can drive spacecraft vast distances without fuel.
Marvel for a moment on what was achieved: A 20-meter sail made of polyimide resin just 0.0075 mm thick was packed into a payload, launched on the back of a rocket, and unfurled in space. The craft rotated 25 times per minute, and extended four “arms” of material folded origamilike, which unraveled and started generating power.
We now have a working model of a spacecraft that could result in a sun-driven mission to Jupiter.
On then, to 2011.
For the Year of the Rabbit, JAXA has a plan for Moon exploration that is more rabbitlike than tigerish. It will hopefully avoid the problems that have hit NASA’s wheeled Mars rovers, which often got stuck in the soft surface dust of the red planet: JAXA wants to use bipedal robots to explore the surface.
Atsuo Takanishi at Waseda University in Tokyo has simulated the conditions of gravity on the Moon to develop ways in which robots could explore the surface. At the moment it looks like the best form of bipedal lunar locomotion — given the Moon’s low gravity and uneven surface — is to make a robot that hops, rabbitlike, with both feet.
I don’t want to get carried away with excitement about Japan’s space exploration, though, because 2010 also saw new hardships appear in the nation’s aging social fabric.
The phrase muen shakai (society of no relationships) has recently become commonplace since it was discovered that some families — the exact number is unknown — had been keeping the dead body of a parent at home, the deaths undeclared, in order to continue to claim the deceased’s state pension.
Japan’s economy and society are nothing like they were a generation ago, and adapting to the changes is an urgent problem. These are massive issues, and the country’s successful year in space exploration tells us little about how to fix them.
Little other than this: At least there exists still the will, desire, inspiration — and funding — to reach for the stars.
Follow Rowan Hooper on Twitter @rowhoop. The second volume of Natural Selections columns translated into Japanese is published by Shinchosha at ¥1,500. The title is “Hito wa Ima mo Shinka Shiteru” (“The Evolving Human”).