NASA Administrator Jared Isaacman Calls for Pluto’s Re-Classification as a Planet

On 28 April 2026, NASA Administrator Jared Isaacman testified before the Senate Appropriations Subcommittee on Commerce, Justice, Science, and Related Agencies while presenting the FY 2027 budget request. Republican Senator Jerry Moran asked about Pluto’s status, referencing its discovery by Clyde Tombaugh. Isaacman answered that he supports restoring Pluto’s planetary status.

Space.comNASA Chief Isaacman backs Pluto’s return as planet, reigniting decades-old classification debateThe Independent

In 2006 International Astronomical Union (IAU) re-classified Pluto as a dwarf planet using three criteria: orbit the Sun, be spherical, and clear its orbit of debris. Pluto meets the first two but shares the Kuiper Belt, failing the third. Critics note Earth and Jupiter also share orbital space with asteroids, questioning the consistency of the clearing rule.

NASA Chief Isaacman backs Pluto’s return as planet, reigniting decades-old classification debateThe Independent

Clyde Tombaugh discovered Pluto in 1930 at Lowell Observatory. New Horizons’ July 2015 flyby showed a 1,400-mile-wide world with five moons, nitrogen-ice glaciers, mountains up to 11,000 feet, and the heart-shaped Tombaugh Regio, indicating active geology but not changing its IAU status.

Space.com

Isaacman said NASA is preparing papers to advance a reconsideration of Pluto’s status and to restore Tombaugh’s credit. IAU press and media coordinator Ramasamy Venugopal acknowledged public sentiment, stating that Pluto now leads a newly defined class of solar-system bodies.

NASA Chief Isaacman backs Pluto’s return as planet, reigniting decades-old classification debate

Planetary scientist Mike Brown, a co-author of the 2006 IAU decision, warned that nostalgia does not alter classification criteria. Astrophysicist Adam Frank called the demotion “really important and really exciting,” emphasizing its scientific value. Their comments illustrate the split between geologic and orbital definitions of a planet.

The Independent

The community remains divided over whether the IAU’s orbital-clearing rule or a geologic definition should decide planethood. Restoring Pluto could raise the planet count to twelve or more, complicating education. No consensus exists on a revised IAU definition, leaving the status debate unresolved.

The Independent

Isaacman’s upcoming papers aim to spark peer-reviewed discussion. Any reclassification will require a formal IAU proposal and vote at a future assembly, where scientific consensus will decide.

Space.com

• “Senator, I am very much in the camp of 'make Pluto a planet again.'” — Jared Isaacman, NASA Administrator

NASA Chief Isaacman backs Pluto’s return as planet, reigniting decades-old classification debate

• “And I would say, we are doing some papers right now on, I think, a position that we would love to escalate through the scientific community to revisit this discussion and ensure that Clyde Tombaugh gets the credit he received once and rightfully deserves to receive again.” — Jared Isaacman, NASA Administrator

NASA Chief Isaacman backs Pluto’s return as planet, reigniting decades-old classification debate

• “While NASA administrators are free to wax nostalgic for the days when Pluto was a planet, the actual scientists working in the field will continue to try to explain and classify objects in the solar system in the way that actually helps us understand the world in which we live,” — Mike Brown, professor of planetary astronomy, Caltech

The Independent

• “really important and really exciting.” — Adam Frank, professor of astrophysics, University of Rochester

The Independent