Galaxies
Galaxy with arms coming from the center
Spiral
Which piece of evidence supports the Big Bang theory
The Universe is expanding
What did the Heliocentric Universe Theory state?
The Sun is the center of the solar system
The closest star to Earth is
The sun
What is the primary force that keeps galaxies, such as the Milky Way, held together?
Gravitational attraction
Circular or oval-shaped
Elliptical
How is the temperature of the universe different now from when it began
It was hot, and now it is cold
Early astronomers once believed Earth was the center of the universe. What was this model called
Geoncentric Model
According to the H-R diagram, where would you find the majority of stars based on their life cycle stage?
Main Sequence
What does the electromagnetic spectrum organize by wavelength?
Forms of energy that travel through space in waves
No clear disk or shape
Irregular galaxy
What is the estimated age of the universe based on the most distant objects observed by astronomers?
~13.7
Which model was replaced by Nicolaus Copernicus's model of the universe?
Geocentric
On an HR diagram, where are the hottest stars usually located?
blue side
Scientists believe that the universe is expanding. Which of the following theories about the formation of the universe best supports this theory
Big Bang Theory
Most abundant type of galaxy
Spiral
Using modern tools, what have astronomers discovered about the expansion of the universe?
The universe expanded rapidly initially and then slowed down, or the universe is expanding at an accelerating rate.
What invention helped with the model of the universe
Telescopes
What is Lumonisty on the H-R Diagram
Brightness
What characteristics do scientists use the electromagnetic spectrum to determine?
The arrangement of different wavelengths of energy.
The types and origins of energy emitted by astronomical objects.
The result of two galaxies colliding
Elliptical
What did the universe begin as
a hot dense point
Why do planets orbit the sun
gravitational pull
A star that is very bright but has a relatively cool surface temperature would most likely appear in which region of an HR diagram and what groupof stars would it belong to
Top right corner (giant)
Which of the following statements correctly describes what a light-year measures
The distance light travels in one year