CH 26 Quiz Astronomy

The first astronomer to show that spiral nebulae (today called spiral galaxies) have large Doppler shifts was

Vesto Slipher

Which type of galaxy is observed to contain mostly older stars?

elliptical

In a distant galaxy, whose light is just arriving from 10 billion light years away, our spectroscope should reveal that the most common element is

hydrogen

If a galaxy contains a great deal of dark matter, what will that do the galaxy's mass-to-light ratio?

increase quite a bit

Compared to the mass of our own Milky Way Galaxy, the total mass we estimate for the Andromeda Galaxy is

somewhat bigger

The Tully-Fisher relation (looking at rotation speeds) only works for:

spiral galaxies

The new instrument that made it possible for Edwin Hubble to demonstrate the existence of other galaxies in the early 1920's was:

the 100-inch reflector on Mount Wilson

Edwin Hubble developed a classification scheme for galaxies. By what characteristic did he classify galaxies?

their shape

Which of the following objects is considered useful to astronomers as a "standard bulb" for determining distances?

type la supernovae

Before you can use Hubble's Law to get the distance to a galaxy, what observation must you make of that galaxy?

you must take a spectrum of the galaxy and measure the red shift

Which of the following statements about the implications of Hubble's Law is FALSE?

if you were observing the universe from a distant galaxy, you would NOT see all the galaxies (except those in your own group) moving away from YOU

Which of the following statements about the different types (shapes) of galaxies is correct?

collisions and mergers between galaxies can sometimes change a galaxy's type (shape)

Which of the following was not done by Edwin Hubble?

discovering the relationship between period and luminosity of a cepheid variable

Which type of galaxy is very difficult to see, but (astronomers recently realized) may be very common?

dwarf elliptical

About two thirds of the nearby spiral galaxies (which we can study in more detail) don't have a round central bulge, but instead show

a central bulge with a bar of stars in the middle

One of the main projects being carried out by the Hubble Space Telescope is to measure the distances of galaxies located in groups dozens of millions of lightyears away. What method do astronomers use with the Hubble to find such distances?

finding Cepheid variables and measuring their periods