Are we alone in the
universe? All of us
have asked ourselves
this question at least
once in our lifetimes. Since
25/09/2016, science has had
at its disposal a powerful tool
with the help of which it will
one day be able to definitively
answer this question.
This is the Five-hundred-Meter
Aperture Spherical Radio Telescope,
or FAST for short, which
has been set up in a natural
depression near to Pingtang in
the south-western province of
Guizhou in China. FAST has a
diameter of 520 metres and is
therefore the largest radio telescope
with a spherical primary
reflector in the world. It thus
supersedes the radio telescope
that was built in Arecibo, Puerto
Rico in 1963 which, with a
diameter of 305 metres, has an
overall surface almost two-thirds
smaller. Indeed, there is an even
bigger radio telescope in the
world, the Ratan 600 in Russia; however, its reflector is not a dish but a ring
made of reflector panels with a diameter of
576 metres. In contrast, FAST’s primary mirror
is made up of 4,450 triangular elements
placed inside a cable mesh. The reflector is
the equivalent of some 30 football pitches.