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A CLOSE-UP
VIEW OF AN
ODDBALL OF THE
SOLAR SYSTEM
TUDYING PLUTOS
I
n January 2006, NASA’s
New Horizons spacecraft
lifted off from Cape Canaveral
on a voyage to the planet Pluto
and beyond. The moment was
testament to the perseverance
of the principal investigator for
New Horizons, Alan Stern.Planetary demotion
At the time, nobody knew what Pluto
actually looked like. It was small
and far away on the inner rim of the
Kuiper belt, and even the mighty
Hubble Space Telescope could only
render it as a pixelated ball of light
and dark patches. Plans to explore
Pluto close-up were thwarted during
the 1990s as NASA budgets wereIN CONTEXT
KEY ASTRONOMER
Alan Stern (1957–)BEFORE
1930 Clyde Tombaugh
discovers Pluto, which is
named as the ninth planet.1992 Pluto is found to be
one of many Kuiper Belt
Objects orbiting the sun
beyond Neptune.2005 Another Pluto-sized
object is found beyond the orbit
of Neptune. It is called Eris.AFTER
2006 Pluto, Eris, and several
other objects are reclassified
as dwarf planets.2016 A skewing of the orbits
of Kuiper Belt Objects suggests
that there is a Neptune-sized
planet much farther out in
space, orbiting the sun every
15,000 years. The search is
now on for this object.