Fireballs

In order to define what a fireball is, we must first talk about meteorites and meteors. A meteoroid is generally defined as an asteroid or comet fragment that orbits the Sun and has an approximate size between ten microns and a meter or so. Meteors, or “shooting stars,” are the visible paths of meteoroids that have entered the Earth’s atmosphere at high velocities. A fireball is an unusually bright meteor that reaches a visual magnitude of -3 or brighter when seen. This would make them brighter than Venus! Objects causing fireball events can exceed one meter in size. Fireballs that explode in the atmosphere are technically referred to as bolides although the terms fireballs and bolides are often used interchangeably.

Asteroids

Asteroids are small, rocky objects that orbit the Sun. Although asteroids orbit the Sun like planets, they are much smaller than planets. They could have a diameter of hundreds of miles, or be as small as pebbles. Most of the asteroids in our solar system are found in the aptly named "Asteroid Belt", which is between Mars and Jupiter.

Comets

Comets are large objects made of dust and ice that orbit the Sun. Best known for their long, streaming tails, these ancient objects are leftovers from the formation of the solar system 4.6 billion years ago. They have orbits that are much longer than Neptunes. The comet with the longest known orbit takes more than 250,000 years to make just one trip around the Sun!