A GIANT comet spotted between the orbits of Uranus and Neptune
is the first object known to have come from an exotic part of
the solar system called the inner Oort cloud. The 100-kilometre-
wide lump of ice was spotted two years ago in an oddly eccentric
orbit around the sun. The comet is now at its closest point,
about 24 astronomical units (AU) away (1 AU is the distance from
the sun to the Earth). The most distant point in its orbit is
nearly 1600 AU from the sun. Comets from the outer Oort cloud
are the only objects known to travel further from the sun,
reaching distances of between 20,000 and 200,000 AU. Theorists
have long predicted the existence of an inner Oort cloud, but
this is the first observation of a body coming from it. This may
be because the sun's gravity is still relatively strong at this
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