Galaxies
These galaxies are populated with dim, red stars and spherical in shape.
What are elliptical galaxies?
This special relativistic phenomenon causes an observer in a moving reference frame to experience time differently than a stationary observer.
What is time dilation?
These objects were first discovered by William Parsons, aka Lord Rosse, from his "Leviathan" observatory.
What are spiral nebulae?
The lowest rung on the distance ladder which allows astronomers to measure the distance to nearby stars?
What is parallax?
True or False: The Big Bang can best be described as an explosion of fully formed galaxies and stars.
False
These galaxies are composed of spiral arms, a halo, and a bulge.
What is a spiral galaxy?
This experiment showed that the speed of light is the same in every direction, irrespective of the Earth's motion.
What is the Michelson-Morley experiment?
The positions of this class of objects seem to suggest that we are on the edge of the Milky Way.
What are globular clusters?
The highest rung on the distance ladder which allows astronomers to measure distances to distant galaxies.
What are Type Ia supernovae?
What is cosmological redshift?
The Milky Way is this type of galaxy.
What is a barred-spiral galaxy?
This prediction from General Relativity is verified by images of background quasars formed by foreground galaxies.
What is gravitational lensing?
This bright radio source is actually a supermassive black hole at the center of our galaxy.
What is Sgr A*?
A galaxy 125 Mpc away is receding at 8750 km/s. What is the Hubble constant?
This prediction from the Big Bang Theory explains how the Universe was initially composed of hydrogen, helium, and a little Lithium.
Big Bang Nucleosynthesis
This type of matter is evidenced by flat galactic rotation curves.
What is dark matter?
This phenomenon revealed the presence of dark matter in the colliding bullet cluster.
What is gravitational lensing?
This led Harlow Shapley to believe spiral nebulae could not possibly be outside the Milky Way.
All galaxies seem to moving away from us, with more distant galaxies moving faster. Does this mean we are the center of the Universe?
No, there is no center.
Radial velocity measurements shows a star oscillating with amplitude 5 km/s. If the planet orbits the star at 500 km/s, what is the planet's projected mass relative to the star?
1/100
Most of the matter in a galaxy is concentrated in this region.
What is a halo?
52.0 kpc
This observation led Heber Curtis to believe that the Milky Way was an "island universe" and Andromeda was outside the Milky Way.
What are detections of novae in Andromeda?
This cosmological parameter causes an accelerating expansion rate of the Universe.
What is dark energy?
A planet transiting a star blocks 1% (0.01) of the star's light. What is the ratio of the planet to stellar radii?
0.10