In what year was Pluto reclassified as a dwarf planet?
1965
1970
2006
2010
Answer
In 2006, the International Astronomical Union (IAU) reclassified Pluto from a planet to a "dwarf planet." This change in classification was due to Pluto not meeting the IAU's criteria for a planet, which requires a celestial body to orbit the Sun, have sufficient mass to assume hydrostatic equilibrium (a nearly round shape), and have "cleared the neighborhood" around its orbit.
Stellar Sleuth: Unraveling the Legacy of Clyde Tombaugh!
Subscribe Now!
Learn something
new everyday
Playing quizzes is free! We send 1 quiz every week to your inbox