Stars
What stage is a star, like our sun, in if it is only going through hydrogen fusion?
Main sequence
What do we call the apparent change in frequency of a wave due to motion?
Doppler effect
What is a huge cloud in deep space consisting of dust and gas; birthplace of stars.
Nebula
What are the kinds of galaxies?
Elliptical, spiral and irregular
What elements make up a main sequence star?
Hydrogen and helium
The larger a star is, the ___________ it's lifespan?
shorter
What theory describes the formation of the universe?
Big Bang Theory
What is an icy body with a tail that has a highly elliptical orbit around the sun?
Comet
What galaxy do we live in
Milky Way
When a main sequence star runs out of this fuel, it cools and expands to form a red giant.
Hydrogen
What process creates the energy that fuels stars?
nuclear fusion
What do we call the microwave radiation that is believed to be left over from the big bang?
Cosmic background radiation
What is a rocky or metallic body that is often referred to as a shooting star?
Meteor
What type of Galaxy do we live in?
Spiral
supernova
What two conditions are necessary for nuclear fusion?
intense heat ( >15 million Kelvin)
pressure
What 3 things can we learn from a stars spectrum?
motion, speed, distance, chemistry
What large rocky objects in space are leftover from planet formation
Asteroids
What is at the center of galaxies?
Black hole
What type of star can create elements up to the atomic mass of iron?
Supergiant
What pathway in the star cycle would a super-massive star take?
Main sequence- supergiant-supernova-black hole
How do we know the universe is expanding?
red shift and Hubbles law
How old is the universe?
13.8 billion or 12-14 billion years
According to Hubbles law, galaxies that are farther away from us are....
moving faster
When a star starts to fuse this element, it's core begins to collapse catastrophically,
Iron