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Article HERE:
Japan will launch the
world's first spacecraft tomorrow drawing its energy from a huge solar-powered
sail. The craft will be launched aboard an H-IIA rocket before unfurling its
ultra-thin membrane 'sail' half the thickness of a human hair once it is in
space Ikaros – which stands for Interplanetary Kite-Craft Accelerated by
Radiation of the Sun – works on the same principle as a yacht, according to the
Japan Aerospace Exploration Agency.
It will be launched
from the island of Tanegashima aboard an H-IIA rocket before unfurling its
ultra-thin membrane "sail" – half the thickness of a human hair –
once it is in space.
Solar particles
emitted by the sun will hit the 66ft sail to propel it through space towards
Venus. Photons bounce off thousands of tiny mirrors to push it through the
resistance-free environment. And as the force acts continuously, a solar sail
will eventually be able to reach speeds that are up to ten times greater than
any rocket powered by conventional chemicals. The 307kg craft also has engines
that draw their energy from solar cells on the craft and act as a
"hybrid" engine, primarily for steering it on its mission.
Yuichi Tsuda, deputy
manager for the project, said: "We believe Ikaros will take six months to
reach Venus, which we will use to test the craft and its responses, but after
that we want it continue to fly for as long and as far as possible."
The team hopes to be
able to operate the vehicle for at least one year after which they expect to
lose contact.
Plans are already
under way for its successor which will be launched towards the end of the
decade and be equipped with a solar power sail with a diameter of 160ft.
The idea for this
form of propulsion has been around since Lithuanian scientist Fredrich Tsander
proposed it in the early 1920s, although the technology required to put the
theory into practice is far more recent, dating from the early 1990s.
NASA and its European
counterpart, the European Space Agency, have suspended research into solar
sails due to budgetary constraints.
Yet the technology is
widely considered to be crucial for space travel in the future, with laser
light replacing sunlight as the ultimate aim. That would enable a future craft
to travel at tens of thousands of miles an hour.
The technology is not
presently suitable for manned missions, according to JAXA's Tsuda, because of
the length of time required to build up power from solar photons in order to
reach acceleration speed.
"In
the future, we hope a larger craft equipped with this technology will be able
to explore Jupiter and we want that mission to go ahead by 2020," he said.
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