Asteriods are small rocky objects that are thought to be left over 4.6 billion years ago from the beginning of the solar system.They are round or irregular shapes up to several hundred km across but most of them are quite small. There are more than 10,000 asteriods lying in the space between Mar and Jupitor.
Scientists believe that these asteriods may be the remains of planets in the space between Mar and Jupitor,which broken up early in the solar system.Thousands of large asteriods have been named. Changes of asteriods colliding with Earth are very small.But some of th asteriods do come close to the Earth,such as Hermes closest appoach of 777,000km.
This an
image of the asteriod