Hubble's Law
What is a good analogy for Hubble's law recession of the galaxies?
Raisins being carried apart by dough in a rising loaf of raisin bread
How long does the sun’s light take to reach Earth?
8 minutes
On larger scales (greater than 200 Mpc), we see what?
Random distribution
What year was the big bang theory was discovered?
1927
What is the end result of a closed universe?
The universe collapsing on itself
What equation determines how we get distance?
Distance = Speed / 70 (Hubble's Constant)
If we are looking at a galaxy that is 2 billion light years away, we see it at what age?
Two billion years younger
What kind of structure is a place in the universe that is almost completely empty of stars and galaxies?
Voids
What was formed about 1 billion years after the big bang?
The first galaxies
What is the actual end result of our universe?
We will keep expanding faster and faster
How long have we known Hubble’s Law within a 5% accuracy?
Within the last 10 years
How was the size of the universe in the past compared to the present?
Smaller
What fraction of the universe’s mass and energy is made of atoms?
4%
We are still unsure about whether or not what Epoch occurred?
The Epoch of Inflation
What is the end result of a flat universe?
The universe will stop expanding
The value of the Hubble constant is directly related to what property of the universe?
Age
Dark energy is measured by what?
Type 1 Supernova
What does Olber’s Paradox ask?
How can the sky be dark if the universe is infinitely old, unchanging, homogeneous, and isotropic?
Why were heavier elements not formed in the Big Bang?
Lighter elements are needed to build heavier elements
In a universe with a flat geometry, two laser beams would do what?
Stay parallel
If a galaxy appears to be moving at 140,000 km/s, what is its distance?
2,000 Mpc (140,000/70)
What two people from Bell Labs detected the cosmic microwave background?
Penzias and Wilson
What two properties being questioned in Olber’s paradox are false.
The universe being infinitely old and unchanging
The cosmic microwave background looks like what?
The surface of the star
If we took two laser pointers and pointed them straight out in what type of cosmic geometry would they cross over each other?
Positive curvature