This high-resolution image captured by NASA's New Horizons spacecraft shows the bright expanse of the western lobe of Pluto’s "heart," or Sputnik Planitia, which is rich in nitrogen, carbon monoxide and methane ices.
Johns Hopkins University scientist Kirby Runyon and his colleagues have proposed new criteria for classifying a planet that would not only label Pluto a planet again, but would label 100 other objects in the solar system as planets, too.
According to Tech Times, the current definition of a planet — last changed by the International Astronomical Union (IAU) in 2006 — requires that a celestial body is in orbit around the Sun, has sufficient mass for its self-gravity to overcome “rigid body forces” so that it retains a nearly round shape and has cleared the neighborhood around its orbit.
Under their new proposed criteria, a planet is “a sub-stellar mass body that has never undergone nuclear fusion” with enough gravitational heft to maintain a roughly round shape, Science Daily reported.
Based on this definition, there could be nearly 110 planets in the solar system, including both Jupiter’s and Earth’s moons.
According to Science Daily, the new definition doesn’t require approval from a central governing body and has already been adapted by scientists at the University of Hawaii.