Pluto re-classified as a dwarf planet
PTStaff: Members of the International Astronomical Union have finally voted on Pluto's status as a planet. Four competing proposals, one of which would have introduced four new planets called "plutons" to the solar system, and another in which a new sub-class of planets called dwarf planets, caused controversy in the astronomical and geophysical communities, as scientists argued over the new definitions. About 5% of the world's astronomers voted at IAU, to decide the new definition of a planet.
Under the new guidelines, a celestial body must have "cleared the neighbourhood around its orbit" to be called a planet. Pluto has an elliptical orbit that overlaps with Neptune, so is disqualified full planet status.
Previous Physics Today news picks on Pluto
Pluto will stay as a planet says IAU
Plutons, its not a particle, its the name of a new class of planets
Debate continues over Pluto definition
List of stories regarding today's vote
Pluto loses 'battle of the planets'
The Guardian
Solar System Shrinks with Pluto's Demotion
NPR
Pluto booted out of league of planets
The Register
Pluto Demoted: No Longer a Planet in Highly Controversial Definition
Space.com
Vote Makes It Official: Pluto Isn’t What It Used to Be
The New York Times
How the Facts Align - As Pluto Is Demoted, Some Look for Scientific Clarity
The Washington Post
