Web Results
Pluto does not meet all three criteria that now define a planet. A planet must orbit around the Sun, have sufficient mass to maintain a nearly round shape, and it must have cleared the neighborhood around its orbit.
Pluto has not cleared the neighboorhood around its orbit. It has been reclassified as a "dwarf planet". More >>

en.wikipedia.org/wiki/Pluto

Pluto (minor-planet designation: 134340 Pluto) is a dwarf planet in the Kuiper belt, a ring of ..... This alone is not enough to protect Pluto; perturbations from the planets (especially Neptune) could alter Pluto's ..... New Horizons in July 2015, because the two cameras on the HST used for these maps were no longer in service.

wonderopolis.org/wonder/why-is-pluto-no-longer-a-planet

The truth is, nothing about Pluto changed, but the definition of a planet did. Once these changes became official, Pluto no longer fit the definition of a planet.

www.bbc.com/news/science-environment-33462184

Jul 13, 2015 ... In 2006, Pluto was demoted from planet status. Why was it removed from the planet club?

www.universetoday.com/13573/why-pluto-is-no-longer-a-planet

Oct 16, 2016 ... Let's find out why Pluto is no longer considered a planet. Pluto was first discovered in 1930 by Clyde W. Tombaugh at the Lowell Observatory in ...

www.loc.gov/rr/scitech/mysteries/pluto.html

The International Astronomical Union (IAU) downgraded the status of Pluto to that of a dwarf planet because it did not meet the three criteria the IAU uses to ...

www.nasa.gov/audience/forstudents/k-4/stories/nasa-knows/what-is-pluto-k4.html

Pluto is a dwarf planet in our solar system. ... A drawing of the orbits of the planets and Pluto ..... Large debris could be satellites that are no longer working.

news.nationalgeographic.com/news/2006/08/060824-pluto-planet.html

Aug 24, 2006 ... Pluto is no longer a planet, according to a new official definition. Instead the icy sphere will be considered one of more than 40 "dwarf planets."

www.planetsforkids.org/why-is-pluto-no-longer-a-planet.html

Pluto used to be known as the smallest planet in our solar system, and the furthest planet from the sun. Pluto was discovered in 1930 by Clyde Tombaugh, ...

www.space.com/2791-pluto-demoted-longer-planet-highly-controversial-definition.html

Aug 24, 2006 ... Officially, Pluto is no longer a planet. "Pluto is dead," said Caltech researcher Mike Brown, who spoke with reporters via a teleconference while ...