Question

in general, galaxies are moving away from one another at an increasing rate, carried by the constant expansion of the universe. on smaller scales, however, the gravitational forces between galaxies can be strong enough to overcome this expansion and pull them closer together. astronomers often use redshift, the phenomenon where light stretches to longer, redder wavelengths as its source moves farther from the observer, to determine the distance between another galaxy and our own. the greater the redshift, the farther the galaxy. for instance, the galaxy gn - z11 has a redshift value of 11.1, making it one of the most distant and ancient galaxies observed. in contrast, galaxy m31, which is moving toward our milky way galaxy, has a negative redshift value, also known as a blueshift. what does the text indicate about gn - z11? choose 1 answer: a it is moving away from the milky way. b its blueshift value is larger than that of m31. c it is moving closer to m31. d it is one of the closest galaxies to the milky way.

Explanation:

• Option A: The text says redshift means a galaxy is moving farther from the observer (Milky Way here), and GN - z11 has a redshift of 11.1, so it's moving away from the Milky Way.
• Option B: GN - z11 has a redshift, not a blueshift, so this is incorrect.
• Option C: There's no information about GN - z11's movement relative to M31, so this is not supported.
• Option D: The text states GN - z11 is one of the most distant galaxies, so this is wrong.

Answer:

A. It is moving away from the Milky Way.