The biggest thing that most associate with the re-entry of a
spacecraft into the Earth’s atmosphere is heat and friction. To
that end, one of the biggest concerns for the space shuttle fleet is
the integrity of the heat shield to allow re-entry without
catastrophic failure such as the Columbia suffered.
Japanese scientists have a wild idea that involves the ancient art
of paper folding known as origami. A prototype shuttle built from
folded paper that was made from sugar cane fibers and sprayed with a
special coating has been able to withstand durability tests in a wind
tunnel at the Tokyo University Department of Aeronautics and
Astronautics. Ultimately, the researchers
want to launch the plane from space and see if it can withstand
re-entry.
Project leader Shinji Suzuki is quoted by Boston.com as
saying, “It sounded like a simply impossible, crazy idea [origami
planes surviving reentry]. I gave it some more thought, and came to
think it may not be ridiculous after all, and could very well survive
if it comes down extremely slowly."
The researchers believe that if the origami planes enter the
earth’s atmosphere at slow enough speed that they would be subject
to much less friction and heat than a full-size space craft like the
space shuttle. Large spacecraft enter the Earth’s atmosphere at
tremendous rates of speed leading to copious amounts of heat
generated from friction.
The small origami paper shuttles measure about 2.8-inches long and
2-inches wide. In wind tunnel testing the origami shuttles survived
wind speeds of up to Mach 7 and temperatures up to 446 degrees
Fahrenheit. These conditions are said to approximate reentry into
Earth’s atmosphere from orbit.
The Japan Aerospace Exploration Agency (JAXA) has agreed to fund
the project for three years with a grant of $300,000 per year. The
program is getting stiff opposition from those who don't understand
why money would be wasted on such a proposal.
Opponents ask what’s the point of the study if the planes can’t
be tracked to determine if they survived reentry. The origami panes
would be launched by astronaut Koichi Wakata by throwing them into
the wake of the ISS as it hurtles through its 250 mile high orbit at
Mach 20.
Suzuki and fellow researchers plan to write messages of peace on
the origami shuttles, the exact number of which would be launched is
not yet determined. Messages on the origami shuttles will also
request that anyone finding the planes notify the researchers.
The launch of origami planes from the ISS would be a perfect use
for the Japanese Kibo lab's open section scheduled to be delivered to
the ISS next year. The first
section of the Kibo lab was delivered by the space shuttle
Endeavor in March 2008.
