AS101 Lecture : September 13.docx
Document Summary
But, many kinds of astronomical objects, gaseous clouds, dust, energy and even dark matter in space. Sun: a large, glowing ball of gas that generates energy through nuclear fusion. Planet: a moderately large object, which orbits a star, it shines by reflected light. Planets may be rocky, icy, or gaseous in composition. Moon or satellite: an object that orbits a planet. Asteroid: a relatively small and rocky object that orbits a star. Comet: a relatively small and icy object that orbits a star. They come from orbits around neptune (and further away). Star system: a star or stars and all the material that orbits it, including planets and moons, comets, and asteroids.
