Pluto was once considered a planet but 13 years ago, the International Astronomical Union changed its status and classified it as a dwarf planet.

Bridenstine Supports Pluto's Planet Status

Many astronomers did not agree with the IAU decision to demote what once was the outermost planet of the Solar System.

NASA Administrator Jim Bridenstine is among those who think that Pluto should still be classified as a planet.

The NASA boss expressed his views on the Pluto debate during a tour of the Aerospace Engineering Sciences Building at the University of Colorado Boulder.

"Just so you know, in my view, Pluto is a planet," Bridenstine said. "You can write that the NASA Administrator declared Pluto a planet once again. I'm sticking by that, it's the way I learnt it, and I'm committed to it."

Bridenstine's view may not officially change the status of Pluto, but his statement supports the clamor to reclassify pluto as a planet.

Why Pluto Was Downgraded To Dwarf Planet

In 2006, the IAU adopted another definition for planethood. Its criteria require that a planet should orbit the sun, has a nearly round shape, and should have "cleared the neighborhood around its orbit."

Pluto did not meet the third criterion, which requires that a planet's orbit must be clear of other objects. Pluto's orbit happens to be filled with small, icy bodies, which resulted in Pluto being reclassified as a dwarf planet.

Scientists Disappointed Over Demotion Of Pluto

A number of scientists, including Alan Stern, principal investigator of the New Horizons mission, expressed their disappointment when Pluto's planet status was downgraded.

"We do not classify objects in astronomy by what they are near," Stern said in 2006 in response to the decision of the IAU. "We classify them by their properties."

In April, Stern engaged in a public debate with former IAU president Ron Ekers over the definition and status of Pluto

He argued that the IAU definition was adopted by the wrong group of astronomers, most of whom were not planetary scientists, but astronomers with other specialties.