知识世界

Astronomy:Spacefiles — Asteroid

Out here， in the great void before Jupiter， is the asteroid belt. It's a vast disk of rocks — a ring of so-called minor planets. Were it not for the disruptive pull of Jupiter， the asteroid belt might have formed a single planet. As it is， orbiting between Mars and Jupiter， the belt is an array of potential projectiles.

• 01

  Astronomy： Threat from Space

  
• 02

  Astronomy： Galileo and the Milky Way

  
• 03

  Astronomy： Spacefiles — Lord of the Rings

  
• 04

  Astronomy： Spacefiles — Venus

  
• 05

  Astronomy： Spacefiles — Sun

  
• 06

  Astronomy： The Story of Aviation

  
• 07

  Astronomy： Spacefiles — Galaxy

  
• 08

  Astronomy： History of the Race to the Moon

  
• 09

  Astronomy： Deep Impact

  
• 10

  Astronomy： Edwin Powell Hubble and the Expanding Universe