Definitions
force that pulls matter together
gravity
a large group of stars, dust, dark matter, and gas
galaxy
Name at least 3 types of nebulae
Diffuse, Emission, Planetary, HII (H2), Bipolar, Reflection, Supernova Remnants, Pulsar Wind, Dark/Absorption
Which nebulae are dark and why? How would you be able to see it best?
Absorption nebulae appear dark, blocking the light behind it due to it being so thick. The best way to see them is with a field of stars or another nebula behind it, to see the edges of the dark nebulae.
How do nebulae form?
gravity pulls matter together
explosion of a star
supernova
an instrument that gathers radio waves from objects in space
radio telescope
How are nebulae classified?
Nebulae are classified by their composition
True or False: The way a nebula interacts with light gives information for their classification.
True
What are the two theories of galaxy formation?
- galaxies formed from many small lumps of matter and dark matter that were already clumped together.
- galaxies were born when vast clouds of dust and gas collapsed under their own gravitational pull.
cloud of interstellar gas and dust
nebula
an entity with gravity so strong that no light can escape it
black hole
What are the three major shape classifications for a galaxy? Briefly describe each.
spiral: center disc with fingers, elliptical: oval and large, irregular: no shape, scattered
What common event causes galaxies to grow in mass and size?
Galaxies collide and merge to form new galaxies, groups, and clusters. As they grow their gravitational pull gets stronger, pulling in more and more matter. Merging is a very slow process.
True or False: Typically, galaxies with relatively high amounts of dust and gas also have younger stars and active star formation.
True. Stars are born in nebulae, which are clouds of interstellar gas and dust.
area with NO matter
vacuum
Explain spaghettification.
when something/someone falls into a black hole and gets stretched to look like spaghetti
Name the four types of Black Holes. Which is the most common and how does it form?
stellar, supermassive, intermediate - mass, miniature
Supermassive; forms after a supernova
When galaxies merge, what does that entail?
mergers do not mean stars collide, because they would be too far spaced. This means the stars get redistributed through their gravitational pulls of energy and mass. This can also lead to more areas of stellar formation (nebulae)
How do black holes form?
after a star burns off its gas, the outward pressure from its radiation emission gets weaker, thus allowing gravity to compact the star and its mass, making it implode! The result is a black hole.
energy carried by fluctuating magnetic and electrical fields
electromagnetic radiation
What is an "event horizon"?
the light around the edges of a black hole
What is the difference between the top-down (outside - in) model and the bottom-up (inside - out) model?
Top down: large gas clouds collapse to form many stars, vs. smaller structures joining to form larger structures
DAILY DOUBLE (BOTH)
What marks the start of the DECLINE in galaxy evolution (a.k.a. "galaxy death")?
When galaxies deplete their gas and dust supply, star formation ends and the galaxy begins its stage of evolutionary death.
Name the order of intergalactic groups, with a brief description, starting with a star.
star: dust and gas; galaxy: stars, gas, dust, dark matter; galaxy group: collection of galaxies; galaxy cluster: collection of galaxy groups