An astronomer discovers a new galaxy using a telescope. The astronomer wants to investigate how the galaxy is moving relative to the Milky Way galaxy. In one or two sentences, make a hypothesis about the movement of the galaxy and explain at least one way to test the hypothesis.
Hypothesis: The newly discovered galaxy is moving away from the Milky Way galaxy due to the expansion of the universe. One way to test this hypothesis is by analyzing the redshift of the galaxy's light, which should indicate if the galaxy's light is stretched towards longer wavelengths, confirming its movement away from us.
Shorter
Shorter answer
Hypothesis: The newly discovered galaxy is moving away from the Milky Way due to the expansion of the universe.
To test this hypothesis, the astronomer can measure the galaxy's redshift. By observing the light emitted by the galaxy, they can examine the shift of the spectral lines towards longer wavelengths. A larger redshift would indicate that the galaxy is moving away from the Milky Way.