Review Questions - Formative Library | Library

1

Describe the main distinguishing features of spiral, elliptical, and irregular galaxies.

1

Why did it take so long for the existence of other galaxies to be established?

1

Explain what the mass-to-light ratio is and why it is smaller in spiral galaxies with regions of star formation than in elliptical galaxies.

1

If we now realize dwarf ellipticals are the most common type of galaxy, why did they escape our notice for so long?

1

What are the two best ways to measure the distance to a nearby spiral galaxy, and how would it be measured?

1

What are the two best ways to measure the distance to a distant, isolated spiral galaxy, and how would it be measured?

1

Why is Hubble’s law considered one of the most important discoveries in the history of astronomy?

1

What does it mean to say that the universe is expanding? What is expanding? For example, is your astronomy classroom expanding? Is the solar system? Why or why not?

1

Was Hubble’s original estimate of the distance to the Andromeda galaxy correct? Explain.

1

Does an elliptical galaxy rotate like a spiral galaxy? Explain.

1

Why does the disk of a spiral galaxy appear dark when viewed edge on?

1

What causes the largest mass-to-light ratio: gas and dust, dark matter, or stars that have burnt out?

1

What is the most useful standard bulb method for determining distances to galaxies?

1

When comparing two isolated spiral galaxies that have the same apparent brightness, but rotate at different rates, what can you say about their relative luminosity?

1

If all distant galaxies are expanding away from us, does this mean we’re at the center of the universe?

1

Is the Hubble constant actually constant?

Please take the time to check out the source for this material from Openstax if you plan to use this in your lesson plan!: https://openstax.org/books/astronomy/pages/26-review-questions