26 terms

Unit 10

The distance that light can travel in one year is called a ____________________.
light year
What process creates energy the core of stars?
nuclear fusion
Stars are born from clouds of dust and gas called __________________.
What conditions are necessary for nuclear fusion to occur?
extreme heat and pressure
In a star's main sequence the element _____________ is being fused into the element _____________.
hydrogen, helium
A star enters its red giant stage when it begins fusing which element?
What do small stars become after their red giant stage?
white dwarf
What is the heaviest element that red supergiants can create by nuclear fusion?
How are elements heavier than iron created?
What object will be created by the supernova when the leftover core is more than 5 times the mass of the Sun?
black hole
What object will be created by the supernova when the leftover core is less than about 5 times the mass of the Sun?
neutron star
What is the name of the galaxy we live in?
Milky Way
One explanation for the accelerating expansion for the universe is an undiscovered form of energy called ________________________.
dark energy
Mysterious matter that doesn't emit light is called ______________________.
dark matter
What is the most widely accepted explanation for how the universe formed?
Big Bang theory
Approximately how old is the universe?
13.7 billion years
Which law states that the farther away a galaxy is, the faster it is moving away
Hubble's Law
What does redshift tell scientists about the universe?
the universe is expanding
A light source that is rapidly moving away from an observer will exhibit ____________.
What shape is the Milky Way galaxy?
Which theory explains that all matter in the universe expanded from a single point?
The Big Bang Theory
The larger a star is, the ____________ its main sequence will be.
The coolest stars burn ________, while the hottest stars burn ________.
red; (yellow, white); blue
From birth to death, our sun is expected to spend a total of __________________ years in its main sequence, before running out of Hydrogen fuel
10 billion years
Which is larger: a solar system or a galaxy?
a galaxy
What happens to the pitch of a car horn as it approaches a listener?
the pitch goes up (increases in frequency)