Which of the following best explains why the night sky is dark?

Which of these items is a key assumption in our most successful models for galaxy formation?

The current temperature of the universe as a whole is

_______________________   _________________ is a mathematical expression of the idea that more distant galaxies move away from us faster: v = H0 × d, where v is a galaxy’s speed away from us, d is its distance, and H0 is Hubble’s constant..

The types of stars called _____________________  ________________  __________________ (three words) are a particularly luminous type of pulsating variable star that follow a period–luminosity relation and hence are very useful for measuring cosmic distances.

The best measurements of the mass of the black hole at the galactic center come from

A method of measuring distances within the solar system by bouncing radio waves off planets is called _________________  ___________________ (two words).

The Model Minority myth is used in reference to which ethnic group in the United States?

Observing our galaxy at radio wavelengths allows us to see through the dust in the disk that obscures our view.

Stars in the _______________ region of the Milky Way galaxy are all old, having a very low proportion of heavy elements.