|
||||||
|
Jump to: Page 1: Intro, The Surface, Page 2: Composition, Brief History, Something Cool, Note COMPOSITION:
Both these models would support the idea
that Charon was formed as a result of an impact on Pluto. If Charon
did form as a result of an impact on Pluto, Pluto's interior
would be very hot. This would lead the softening of ice and
separation of rock from the core. BRIEF HISTORY: An American astronomer named Percival Lowell first documented the idea of a distant ninth planet in 1905. Based on erroneous calculations (although, Lowell did not know they were incorrect at the time), Lowell predicted a planet beyond Neptune that was affecting the movements of Neptune and Uranus. He proceeded to continue his search for his mysterious planet, going so far as predicting a possible area the planet could be found. However, it wasn't until the year 1930 that the planet was finally discovered by Clyde W. Tombaugh. In honor of Lowell, who had passed away in 1916 without fulfilling his dream, Tombaugh named the planet after the Roman god of the dead. However, this planet's mass was too small to be the one causing the discrepancies. The search for Planet X continued until Voyager 2 determined a new, correct mass for Neptune. Using the new mass of Neptune, there was no longer a discrepancy in calculations. In 1978, James Christy, an astronomer at the U.S. Naval Observatory in Flagstaff, Arizona, discovered a moon for Pluto. Named Charon, the moon had a diameter of only 740 miles(1,190 kilometers). SOMETHING COOL: Pluto's orbit takes it 249 years to complete and has a 3:2 resonance with Neptune. This means its orbital period is 1.5 times longer than Neptune's is. Usually, its orbit puts it as the farthest planet from the Sun. However, for 20 years of its trip around the Sun, its orbit takes it inside Neptune's orbit. For these 20 years, Pluto is the eighth planet from the Sun. The most recent orbit crossing took place on January 21, 1979 when Pluto came inside Neptune's orbit. They switched back on February 11, 1999. This will not occur again until September 2226. Pluto and Neptune never collide as their orbits cross because as Pluto reaches perihelion, the closest it ever comes to the Sun, it is at its maximum degree of inclination. When the two planets pass by each other, Pluto is usually well below or above the plane Neptune's orbit is on. The closest the planets come together is approximately 18 A.U.
NOTE: |
||||||
 |
 |
 |
|
Page 2 of 2 Home
Pluto-Kuiper
Intro
|
