Question

1. why are parsecs, megaparsecs, and gigaparsecs necessary in addition to the light - year when studying distances in space? different galaxies have different measurement systems. the parsecs, megaparsecs, and gigaparsecs are measurements used outside of the milky way galaxy. in space, the light - year is a small unit of distance, and additional measurements are necessary to be able to measure everything in space. the light - year is too massive of a measurement, and other smaller measurements are needed to measure things in space. parsecs, megaparsecs, and gigaparsecs are used to measure the speed of sound, and the light - year is used to measure the speed of light. both are necessary measurements in space.

Explanation:

Light - years are useful for general distance measurements in space, but for very large distances, especially those outside the Milky - Way galaxy, parsecs, megaparsecs, and gigaparsecs are more appropriate. A parsec is defined based on the parallax effect and is a more convenient unit for measuring the vast inter - galactic distances. These units are used to simplify the representation of extremely large cosmic distances.

Answer:

Parsecs, megaparsecs, and gigaparsecs are necessary for measuring extremely large distances in space, especially those outside the Milky - Way galaxy. The light - year is a good unit for general space distances but becomes cumbersome for very large scales. Parsec - based units are more suitable for the huge distances between galaxies and other far - flung celestial objects.