Can someone help me with these astronomy questions? I am stumped!
Which of the following is an actual observation that falsifies (is inconsistent with) the theory that the Milky Way galaxy originated from the collapse of a spherical gas cloud that flattened into a disk?
a. We observe fewer white dwarf stars in the galactic disk than there should be for an 11-billion year old galactic disk.
b. The globular cluster stars in the galaxy halo are all old.
c. The metallicity of globular cluster stars is about one tenth the Sun's value.
d. Nonsense - all of the above observations are consistent with the standard collapse-from-a-cloud theory.
Which of the following is a correct list of distance indicators (standard candles) used by astronomers?
a. emission and reflection nebulae in molecular clouds; nova explosions on white dwarfs; main-sequence stars
b. white dwarf stars; Cepheid variables; black hole binary systems; massive star supernovae
c. lyra and cepheid variable stars; white-dwarf supernovae
d. emission by super-massive black holes located at the center of nearly every large galaxy; spinning spiral galaxies
Which of the following arguments supports the idea that large elliptical galaxies formed by mergers of smaller galaxies?
a. Big ellipticals lack gas and dust, and galactic collisions can allow central supermassive black holes to consume all pre-existing gas and dust.
b. Big ellipticals are generally found near the center of rich galaxy clusters containing many individual galaxies.
c. Ellipticals have lots of gas and dust, and collisions can spur star formation that also forms gas and dust.
d. All the above arguments support the idea of galaxy mergers forming big elliptical galaxies.
Dwarf detonation supernovae (type Ia) are useful standard candles for measuring large distances because
a. the periodicity of the light curve is tightly correlated with the peak luminosity.
b. the exploding star has about the same mass and composition in each case, it is bright, and the light curve is always the same.
c. the explosion is recurrent, and the time between explosions correlates with the peak luminosity.
d. the rotation rate of the object is easily measured and correlates with the peak luminosity.
e. none of the above 鈥?supernovae are useless for measuring distances
Thanks!!|||We're not here to do your homework.
You could at lest break this up into several questions, and rephrase those questions so they aren't duplicates of your homework. Make your questions so that they help lead you to the right answer.|||You want me to do that much work for mere points?
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