No flies here.
The spider "Arabella" spins a web on Skylab.
Beyond the protective blanket of the
Earth's atmosphere, space is filled
with radiation of all kinds: the light
and heat from the Sun, radio waves
from Jupiter, X-rays and gamma rays
from the Sun and from energetic,
poorly-understood objects beyond
our solar system. This radiation not
only spans the electromagnetic spectrum,
but also includes atomic and
subatomic particles of all dimensions
and energies. Much of the radiation
is similar to that which can be produced
on Earth, using radar, cyclotrons,
or radioactive materials. The biological
effects of these radiations can
be studied in great detail. Other space
radiations, such as the highly energetic
HZE atomic particles, or cosmic
rays, are unique to space and can be
duplicated only imprecisely and with
the greatest difficulty on Earth.
Cosmic rays have been studied in
great detail, using a variety of detectors
carried into space. One very sensitive
detector turned out to be the
human eye. Cosmic rays apparently
are the cause of the "light flashes",
bright streaks seen by the astronauts
when their eyes were closed. Some
of the displays were striking. On one
lunar trip, brilliant green flashes were
seen, causing the astronauts to report,
"It looks like St. Patrick's Day."
There is no doubt that such penetrating
radiation can produce biological
damage. It is not yet clear that
this radiation is any barrier to our
progress into space, but we will need
to be protected against it. How the
radiation causes damage, what the
dangerous exposure times are, and
what the possible protective measures
may be are all subjects of in
tense scrutiny.
