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pianeta

Pianeta is the Italian word for planet, and in astronomy denotes a large body that orbits a star, has sufficient mass to assume a nearly round shape, and has cleared its orbital neighborhood of other debris. The International Astronomical Union formalized this definition in 2006.

Etymology traces the term to planētēs, a Greek word meaning wanderer, via Latin planeta and the Italian

In the Solar System, eight planets orbit the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and

Beyond the Solar System, planets orbiting other stars are called exoplanets. Thousands have been discovered through

Planet formation is believed to occur in protoplanetary disks around young stars, through accretion of material

pianeta.
The
name
reflects
the
historical
observation
that
planets
move
against
the
background
of
stars.
Neptune.
Pluto
was
reclassified
as
a
dwarf
planet
by
the
IAU
in
2006.
Planets
are
often
categorized
as
terrestrial
(rocky)
planets—Mercury,
Venus,
Earth,
and
Mars—and
giant
planets,
including
gas
giants
(Jupiter
and
Saturn)
and
ice
giants
(Uranus
and
Neptune).
They
vary
in
size,
composition,
and
distance
from
their
star,
and
many
host
moons
and,
in
some
cases,
ring
systems.
methods
such
as
transits,
radial
velocity,
direct
imaging,
and
gravitational
microlensing.
Exoplanet
discoveries
reveal
a
diversity
of
worlds,
from
small
rocky
bodies
to
massive
gas
giants,
with
many
in
or
near
the
habitable
zone
of
their
stars.
and,
in
some
cases,
migration
within
the
disk.
The
study
of
pianeti
encompasses
planetary
science,
astrobiology,
and
the
ongoing
search
for
life
beyond
Earth.