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Telescopes and space missions

Telescopes and space missions

Pluto relegated to dwarf status

25 Aug 2006 Hamish Johnston

Considered by many to be the ninth planet in the solar system, Pluto is now defined as a “dwarf planet” by the International Astronomical Union (IAU). The controversial decision was made yesterday and is based on the fact that Pluto’s orbital path overlaps with other objects such as asteroids and the planet Neptune.

Pluto and Charon
Dissenting astronomers have called the decision arbitrary, pointing out that some other planets (inc

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