It saddens me that my children will grow up seeing only eight planets on the posters at school, whereas I grew up with nine. As of August 2006, Pluto has been classified as a dwarf planet. RTB astrophysicist Jeff Zweerink isn’t as sentimental as I am about Pluto—he understands and appreciates the reasons for the former planet’s demotion.
The discovery of the Kuiper belt brought Pluto’s qualifications as a planet into question. Since 1992, astronomers have cataloged more than 1,000 objects of substantial size occupying the region beyond Neptune. As an occupant of that region, Pluto is considered a member of the Kuiper belt.
This region helps answer a young-earth challenge to the old-earth view, namely the source of comets. It’s known that one class of comets is short-lived—yet we still see them in our solar system. Young-earth creationists argue that this circumstance indicates the solar system is far younger than scientists believe. How else can we account for the appearance of short-lived comets in our cosmic neighborhood?
The Kuiper belt provides an alternative explanation. Astronomers believe this object field comprises the source of the short-period comets that visit our planetary neighborhood. Thus, our solar system contains a mechanism for supplying short-period comets and asteroids, which have supplied Earth with water and other life-essential elements, despite being billions of years old.
Still, some in the young-earth camp have questioned the Kuiper belts’ supply of comet-sized objects. RTB physicist Dave Rogstad reports on research that answers these challenges.
“New Data on Comets”: Yet more research reveals objects small enough to be comets in the Kuiper belt
Pluto may be exiled from the planet club, but as a member of the Kuiper belt it looks like it’s still in good company.
— Maureen
Resources: Asteroids and comets played an important role in preparing Earth for advanced life. Search “bombardment” on the RTB website to get the details.
The universe is incredibly massive. Nevertheless, its mass must be spectacularly fine-tuned for life to be possible. Exactly how massive the universe is remained...
