Astronomy 101 Quiz: Gravity and Stars

Study Notes

Calculating gravitational force will be on the test. Equations for time until hitting the ground are not needed.
Nucleosynthesis is a topic on the exam.

Electrons jump to higher energy levels then release light as they fall to lower levels.
Blueshift is associated with Andromeda.
Maisie's galaxy is the farthest observed object.
Cosmic background radiation (2.75 Kelvin) is almost absolute zero.

Stars are huge orbs of plasma held together by gravity.
Saturn, Uranus, and Neptune are described.
Pluto is not considered a planet.
Stellar explosions can result in black holes or neutron stars.
Greenhouse gases like carbon dioxide and methane are mentioned.
Evidence of past water on Mars (deltas).
Jupiter has a large, long-lasting storm.
Galilean moons (Io, Ganymede, Callisto, Europa) are discussed, with Europa having a subsurface ocean.
Bennu's composition hasn't changed in 4.5 billion years.

Stars form from nebulae and eventually die, transforming into different objects (white dwarfs, neutron stars, black holes)
Stars fuse hydrogen into helium (fusion is essential)
Lifetimes depend on the mass of stars.
The stages of stellar evolution are discussed, including the core, radiative zone, convective zone, photosphere, and corona.
Stars start as a nebula. The gas clumps due to gravity to form nebulae and later many stars. The spinning disk attracts more mass and creates a protostar.
After millions of years, the core is hot enough for nuclear fusion.
Fusing elements results in heavier elements.
Fusion leads to lighter elements, not heavier ones
Fission is not present in stars.
Every star has had exoplanets.
Alpha Centauri is a trinary star system.
Stars frequently form in pairs.

Population I stars (like our Sun) have high metal content, and are found in spiral arms.
Population II stars have low metal content and are found in the galactic bulge.
Population III stars have not been seen and are hypothesized and are composed of no metal.
Population I, II, III stars have varying masses, lifetimes, and roles in nucleosynthesis of heavy metals.

The Hertzsprung-Russell Diagram (HR diagram) plotted and shows the relationship between star absolute magnitudes/luminosities and their spectral classifications/effective temperatures to understand the relationship between temperature & luminosity of stars.
Diagrams depict stars on a graph with luminosity on the y-axis and temperature (spectral type) on the x-axis.
The upper left corner includes hot, bright blue stars, and lower right contains cooler stars.