Small solar system bodies orbiting the Sun
- Asteroids are also called planetoids or minor planets.
- Asteroids are similar to comets but do not have a visible coma, the tail.
- Majority of asteriods can be seen in the asteroid belt between the orbits of Mars and Jupiter or co-orbital with Jupiter (the Jupiter Trojans).
- Newly disoveried asteriods in the early days are assigned iconic symbols
- Ceres, discovered in 1801 by Giuseppe Piazzi, is the first asteroid.
- Ceres, is about the size of Texas.
- Astrophotography, introduced in 1891, is a method to detect asteroids.
- The dust covering an asteroid is called dust is called regolith.
- The Chicxulub impact crater, aging to be 65 million years old, is believed to be responsible for the extinction of all dinosaurs.