Intro Astronomy chapter 1

Smallest to largest; galaxy, solar system, asteroid and universe

Asteroid, solar syatem, galaxy, universe

Which of the following is a distance?
A) 500 ly
B) 500 years

500ly

Astronomy

The study of the universe

Light-year

Distance light travels in a year

Massive

Containing Mass

Satellite

A body that orbits another body

Scientific Method

Is a systematic way of testing new ideas

Hypothesis

An idea that can explain a phenomenon

Falsified

Proven wrong

Theory

Hypothesis which test have failed to disprove

Cosmological principle

The testable assumption that the same physical laws that apply here and now also apply everywhere and at all times

Occam's Razor

The principle that the simplest hypothesis is the most likely

T/F: A light year is the distance light travels in one year?

True

The milky way galaxy?

Contains about 100 billion stars

How may cm in a km?

100000