The likelihood of this explanation has been underscored by the actual observation of comet [[Shoemaker-Levy]] hitting the planet [[Jupiter]] in 1994. This event made huge marks on Jupiter that could be seen by amateur astronomers with backyard telescopes. It has also been underscored by the recent realization that large numbers of asteroids come surprisingly close to Earth. | The likelihood of this explanation has been underscored by the actual observation of comet [[Shoemaker-Levy]] hitting the planet [[Jupiter]] in 1994. This event made huge marks on Jupiter that could be seen by amateur astronomers with backyard telescopes. It has also been underscored by the recent realization that large numbers of asteroids come surprisingly close to Earth. |