Chap 3 locating places
What you need to know to pass the test!. Light year: the distance light travels in one year Light is the fastest-moving stuff in the universe. It travels.
A scientific model. Why do we use the model of the celestial sphere when studying the night sky, even though it does not accurately represent three-dimensional.
Celestial Sphere Facts: It’s an imaginary sphere with earth in the center. It is useful for locating constellations and stars on a star map.
ASTRONOMY
Astrophysics --- History of Exploring the Universe
