Hello,

It is unlikely that scientists will change the status of Pluto back to a planet. There were many scientifically sound reasons why Pluto was re-classified. Pluto is massive enough for its shape to be controlled by gravitation, but it has not cleared its orbit of other objects. Pluto's orbit crosses inside the orbit of the planet Neptune, which is a much larger object than Pluto, so Pluto is now designated as a dwarf or minor planet. Long before scientists decided that planets had to have cleared their orbits of other objects, we already knew that Pluto didn't quite fit in with the other planets. Pluto's orbit is very different from that of the planets. The major planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune all orbit around the Sun within a few degrees of what astronomers call the ecliptic plane. Pluto's orbit is inclined at about 17 degrees to the ecliptic. We don't know a lot about Pluto's composition, but it appears to be made of rock and ice similar to other Kuiper belt objects. This composition is very different from the inner, rocky planets Mercury, Venus, Earth, and Mars. Pluto's composition also does not fit with the compositions of the gas giant planets Jupiter, Saturn, Uranus, and Neptune.

Pluto is now known to have five natural satellites - Charon, Nix, Hydra, Kerberos, and Styx. These satellites have orbits that are unusually close to Pluto compared to the natural satellites or moons of the planets. Having moons is NOT a sufficient condition for an object in the solar system to be declared a planet. Even if additional natural satellites are discovered orbiting around Pluto, the status of Pluto will not be upgraded to major planet.

A lot of people have rejected the change in Pluto's designation for sentimental reasons. Unfortunately, this is not how science works. As we gain more knowledge about something, we may discover that our previous ideas were incorrect. Scientific progress can only be made if we let go of old ideas and make way for new ones. This does not just happen in the space sciences. After performing DNA analysis on various types of Laelia, Oncidium, and Vanilla orchids scientists are now reclassifying some of these plants into new genera.

Kris