Exam 18: Our Expanding Universe

Type I supernovae have an absolute magnitude of -20.If you discover a Type I supernovae in a distant galaxy that has an apparent magnitude of 22,then how far away is this galaxy?

The CBR contains photons left over from the epoch in the universe's history when electrons recombined with nuclei.

Name two predictions of the standard Big Bang theory that have been verified by observations.

What were the positions taken by Heber Curtis and Harlow Shapley in their "Great Debate," and how were both of them partially correct?

Why are some galaxies' spectra blueshifted rather than redshifted?

The current temperature of the cosmic background radiation of 2.73 K means that the peak of its spectrum occurs at a wavelength of

If the wavelength of the background radiation peaked at 1 $\mu$ m at the time of recombination,how old was the universe then compared to its age today?

In the early 1960s,physicists named Penzias and Wilson detected a persistent noise at a wavelength of 1 mm in their radio telescope that came from all directions in the sky due to

The spectra of most galaxies tell us that

If the distance of a galaxy at a redshift is 1,800 Mpc,how many years back into the past are we looking when we observe this galaxy?