My first Magazine 1930's quello verissimo | Page 6

Pluto’s
discovery
At first the existence of a ninth planet was
proposed by Percival Lowell: his theory was that
wobbles in the orbits of Uranus and Neptune
were caused by the gravitational pull of an
unknown planetary body. But in 1929, the
search for Pluto was resumed at the Lowell
Observatory in Arizona. On February 18, 1930,
Tombaugh discovered the planet with a new
astronomic technique of photographic plates
combined with a blink microscope. His finding
was confirmed by several other astronomers,
and on March 14, 1930 the discovery of Pluto
was publicly announced. This Planet was called
Pluto in 1930, a name suggested by an 11-year-
old girl in Oxford. This name was favored by
the astronomers of Lowell Observatory because
its first two letters were the initials of Percival
Lowell. In reality, the discovery had nothing to
do with Lowell's calculations.
http://pluto.jhuapl.edu/Participate/learn/
What-We-Know.php?link=Discovery-of-
Pluto