Clyde Tombaugh's discovery of Pluto in 1905 sparked discussions that are continuing today.
"Pluto is one of the awkward objects. It's not a proper planet because it's only got a quarter of the mass of the Moon and is quite likely a collection of condensed comets."
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9 minutes
Βι¶ΉΤΌΕΔ World Service Archive
This programme was restored as part of the World Service archive project
