00:00How does radiation from the Sun affect the Moon?
00:10Our Sun emits not only light and heat, it also sends high-energy gamma and X-rays out
00:17into space, along with a stream of electrically charged particles we call the solar wind.
00:25Unlike Earth, the Moon has no magnetic field or atmosphere, so radiation from the Sun and
00:32the solar wind bombard its surface constantly.
00:36When the Sun shines, the Moon's surface quickly heats up to around 130 degrees Celsius, where
00:43their shadow temperatures fall to minus 160 degrees.
00:49The extreme temperature swings cause stress to build up in the lunar soil, and tremors
00:55can occur.
00:57Cracks form as the rock crumbles into dust.
01:00The entire Moon is covered in it, in some places up to 15 meters high.
01:07And this dust has sharp edges, posing a danger to both technology and astronauts.
01:17Radiation from the Sun and the solar wind also change the chemical composition of the
01:22Moon's surface.
01:24They can give rise to tiny nanoparticles of iron in the lunar dust, making it darker
01:30and reddish over time.
01:33This process has been studied with probes in lunar orbit.
01:37They show that in the bright highlands, which are exposed to lots of sunlight, the rock
01:42weathers much more quickly.
01:46When the solar wind grows powerful, its electrically charged particles can also knock atoms out
01:53of the lunar rock and blow them into space.
01:56The Moon can then lose as much as 200 tons of material in just a couple of days.
02:04The solar particles can also cause water to form in the rock, and then break it down again.
02:11And in the polar regions, where the solar wind only grazes the surface, craters can
02:16even grow electrically charged.
02:19Radiation and particles from the Sun will present a major challenge to Moon exploration.
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