The Maturity Hypothesis

All of the recent controversy about whether Pluto should have the status of a planet opens up a new way of thinking about the Solar System.

We know that a star, such as the sun, in the process of formation undergoes coalescence by gravity. Matter outside the star but within it's field of gravity also undergoes coalescence of it's own, gradually forming into planets by gravitational attraction. The speed of coalescence depends upon getting matter to meet up with other matter. The process will be faster if there is more matter or if matter is moving faster in a given zone so that it becomes more likely to meet up with other matter and join by gravitational attraction. The result is concentric gravitational nodes around the sun or star that form what we know as planets.

Near the sun there is a sparse zone of matter because the sun's strong gravity can pull it in. This is reflected in the fact that Mercury is a small planet. Further out, there is a denser zone which gradually thins out as we get further from the sun and it's gravity thus becomes weaker. Thus, we find the largest planets in the Solar System outside the inner sparse zone but inside the outer sparse zone.

Of course, heat is another factor in planet size. Jupiter, Saturn, Uranus and, Neptune, the largest planets, exist in a zone where gases on earth such as methane are liquid or solid. You may notice that these four large planets get progressively smaller as we get further from the sun.

In deciding on Pluto's right to planethood, who says that the Solar System is finished? My hypothesis is that there is a "Zone of Maturity" that over billions of years moves outward from the sun. I will define the concept of maturity as the incorporation of all matter in a concentric zone from the sun into the main gravitational node in that concentric zone, namely a planet.

This, however, takes time. In fact, lots of time. It may go on for long after the sun ceases to shine. Since the planets closest to the sun move fastest and have the least orbital path distance, they will scoop up all the loose matter that they are ever going to in much less time than the outer planets.

A planet is a manifestation of a concentric gravitational node around a star or the sun. Not until maturity are the two one and the same. Pluto is maturing much slower than the earth did because it moves through space only about one sixth as fast as earth does and thus will take much longer to collect all of the matter that it ever will.

The Kuiper Belt, debris around and beyond the orbit of Pluto, is a sparse cold version of what the inner Solar System was once like. All planets are still growing due to the reception of materials from space but Pluto has a lot more growth to go than earth does because it moves so slow through space. In the outer reaches of the Solar System, planets orbit slowly over vast distances, matter is sparse and maturity is late.

It is well know that Pluto has not yet cleared all of the matter in it's path. This is, in fact, one of the reasons that many astronomers want to deny it planetary status. But that matter represents future growth for Pluto. This Solar System is only about five billion (5,000 million) years old. Pluto might need another ten or thirty billion to reach full maturity.

Another factor is moons. Under my hypothesis, a moon around a planet is a part of the gravitational node also. In perfect maturity, moons would not exist. But in practice, a moon is a part of a planet's "metropolitan area" and counts as a part of the gravitational node. Pluto's moon, Charon, is very large and adds a lot to the total mass of Pluto's gravitational node. Moons actually accelerate maturity because they spread the gravitational "net" over a wider area.

Under this hypothesis, not only Pluto but also Xena and Sedna are considered as planets. The factor that blinds us on earth to the concept of maturity is the asteroid belt between Mars and Jupiter. The asteroids are prevented from coalescing into a planet, maturing, by the powerful gravity of Jupiter. This leaves debris floating around the inner Solar System.

When Jupiter disrupts the orbits of some asteroids, some of which lands on earth. If not for these asteroids, we would see the relatively pure maturity of the Solar System and the Zone of Maturity moving slowly outward. We would see that the zone had not yet passed Pluto and would not be so quick to revoke it's planetary status.