Scientific Method
The first step of the scientific method is to make an _______.
observation
The Universe began with the ___ ____.
Big Bang
The disproven idea that the universe revolves around the Earth is known as the _____ view.
geocentric
Stars appear to move circularly in the sky each night because of Earth's ____.
rotation
Earth is closest to the Sun during ____.
perihelion
Before designing an experiment, you need to come up with a _____.
hypothesis
Protons, neutrons, and electrons make up _____.
atoms
Copernicus developed the ___ ____ model.
Solar System
Some constellations are only visible for part of the year because of the Earth's ____ around the Sun.
revolution
Earth is farthest from the Sun during ____.
aphelion
This variable is manipulated to test an outcome.
independent variable
The Milky Way is an example of a _____.
galaxy
During the 1400s and 1500s, tension arose between astronomers and the ______.
Church
These constellations remain visible in our sky throughout the year.
circumpolar
Planetary orbits are not circular, but instead are ____.
elliptical
This variable is actively studied in an experiment.
dependent variable
The universe is approximately ____ years old.
14 billion
Early astronomers believed that stars rotated around Earth as part of the ____ ____.
celestial sphere
This term refers to a star's horizontal angular distance from North.
azimuth
inertia
This type of variable is kept constant throughout an experiment.
control variable
The Earth is approximately ____ years old.
4.6 billion
This two-word phenomenon describes the periodic apparent backward motion of planets in our night sky.
retrograde motion
Astronomers "map" the stars using the
Horizontal Coordinate System
The apparent shift in a star's position due to Earth's revolution is called the ____ _____.
stellar parallax