This is how we can observe the life histories of galaxies.
What is we can look farther away to see how galaxies were in the past and look closer to see how they have developed?
100
The two factors that influence whether a galaxy is formed as a spiral galaxy or an elliptical galaxy.
What are protogalactic spin and protogalactic density?
100
Definition of a quasar.
What is a very bright active galactic nucleus (nucleus of a galaxy that is too far away to tell what shape it is) with huge energy outputs from huge accretion disks surrounding supermassive black holes with masses millions or billions of times the mass of the Sun? Also they radiate over a wide range of wavelengths and contain materials of different temperatures so they have multiple peaks on a light curve.
100
What a rotation curve shows.
What is rotational velocity of stars/clouds vs. distance from center of galaxy?
100
The role of dark matter in the creation of galaxies.
What is that dark matter provided most of the gravitational attraction responsible for creating protogalactic clouds; dark matter remained in the outskirts (halo) of the galaxy while hydrogen and helium collapsed inward and formed stars; brings galaxies together that end up in clusters?
200
When the universe was young, these gases filled space almost uniformly.
What are hydrogen and helium gas?
200
This is why collisions between galaxies were more common in the past.
What is because galaxies were all closer together in the past?
200
Are there quasars closer to us?
Maybe dead/dormant ones yup
200
What it means if the rotation curve flattens out.
What is that there is a ton of mass concentrated outside of the center of the galaxy, probably dark matter?
200
Maps of the universe who these two large-scale structures.
What are chains/sheets/walls and voids?
300
Certain regions in the universe started out with slightly more ___ than other regions.
What is density?
300
What is formed when 2 spiral galaxies collide and why?
Oops I messed up, sorry. An elliptical galaxy is formed because tidal forces tear apart the disks and gas sinks to the center while winds blow away the rest of the gas.
300
A radio galaxy.
What is a galaxy with an active nucleus shooting out jets of plasma in opposite directions that hit gas and create hot spots in lobes which make larger lobes but don't appear as quasars because dust blocks them?
300
The composition of a typical spiral galaxy.
What is 90% dark matter and 10% matter in stars?
300
Critical density.
What is the density of the universe that divides between ultimate collapse or expansion? If the density is greater than the critical density, then gravity can win out over expansion.
400
This is how protogalactic clouds were formed.
What is that the expansion of denser regions stopped and reversed because of gravity and contracted to form protogalactic clouds?
400
This is the reason why there are more elliptical galaxies at the centers of galaxy clusters.
What is because there are lots of collisions there?
400
The power source for quasars and other active galactic nuclei.
What is accretion of gas falling onto a supermassive black hole?
400
Gravitational lensing.
What is when massive objects bend passing light beams because their mass distorts spacetime and multiple images or single distorted images of galaxies behind the lensing clusters are visible?
400
The four expansion patterns.
What are recollapsing, critical, coasting, and accelerating? **know what they are too
500
The kind of stars that were initially formed in protogalactic clouds before gas settled into a rotating disk.
What are large, short-lived stars?
500
A starburst galaxy.
What is a galaxy that forms stars at a rapid rate, and the intensity of its supernovae can create strong galactic winds?
500
Mass of bulge is related to the mass of the galaxy's ___.
What is central black hole?
500
What ordinary and extraordinary dark matter is made of?
What are MACHOs (massive compact halo objects) that are too faint to see like brown dwarfs and WIMPs (weakly interacting massive particles) that are hypothetical but travel fast like neutrinos but are more massive?
500
What will happen to our universe?
What is never-ending expansion because gravity is too weak to stop it (we think)?