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The Solar System
Minor Bodies: Remnants from the Beginning
The Solar System Guide

Although they lack the glamour of the major planets and moons, the ‘leftover' asteroids and comets contain clues to the birth of the solar system, and present both threats and opportunities for the future. More »


Pluto
After 76 years of glory, the small ball of rock and ice known as Pluto was relegated to the solar system backwaters in 2006 when astronomers dropped it from the list of planets.
After 76 years of glory, the small ball of rock and ice known as Pluto was relegated to the solar system backwaters in 2006 when astronomers dropped it from the list of planets. More»		 Charon: Double Planet?
While some scientists say that Pluto should not be considered a planet at all, others think of it as a double planet.
While some scientists say that Pluto should not be considered a planet at all, others think of it as a double planet. More»
Great Dates

1705
Edmund Halley calculates that a previously seen comet will return in 1758; when it does, astronomers name it in Halley's honor

1801
Giuseppi Piazzi discovers Ceres, the first asteroid

1898
Gustav Witt discovers 433 Eros, the first near-Earth asteroid; a spacecraft lands on it more than a century later

1950
Fred Whipple describes comets as ‘dirty snowballs'

1980
Father-and-son team of Luis and Walter Alvarez suggest that an asteroid impact killed the dinosaurs

1991
Galileo makes the first flyby of an asteroid, Gaspra

1994
The fragments of Comet Shoemaker-Levy 9 hit Jupiter

2005
Mike Brown and colleagues discover a possible 10th planet in the Kuiper Belt

 
Comets
Comets
With the possible exception of Saturn's rings, comets are the most beautiful objects in the solar system. More» 		Asteroids
Eros
Asteroids are made of rock and metal. More»
Meteorites
Mars meteorite
Most meteorites are pieces of asteroids. More

See Also...

FAQs about the solar system.

Featured images about the solar system.

Keywords about stars and nebulae.

  

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