AST101H5 Lecture : AST101-Chapter 7&9.txt
Document Summary
Solar system has many objects smaller than the major planets: Aster (=star) + oid (=body) - an object that looks like a star, but it orbits t he sun. 1. largest (now known) = 1000 km in diameter. 3. more than 400,000 asteroids have been catalogued, but many more have been detected. 4. there are probably more than 1 million asteroids larger than 1km. Most asteroids orbit between mars and jupiter = main asteroid belt . Jupiter"s powerful gravity controls the spacing of these orbits. These are captured by gravity of jupiter + sun. Orbit from close to sun and to beyond jupiter. Meteoroids are tiny asteroids, rocks too small to observe from earth -m -> dust. Meteoroids orbit at ~ 30 km/s - like earth. 2. it gives off a flash of light as it disintegrates, called a meteor or shooti ng star .
