what was one of the great discoveries in astronomy during the 20th century?
One of the great discoveries in astronomy during the twentieth century was that
A) there used to be life on Mars.
B) at the largest scale, galaxies are randomly distributed in space.
C) our star, the Sun, is located outside of the Milky Way.
D) our galaxy is alone amongst the other galaxies; it is not part of a cluster of galaxies.
E) our galaxy is only one of many billions in the universe.
e
A and C i believe
E is the only accurate one.
Ignore the first answerer, they don’t know what the hell they’re talking about.