How does an object’s motion change as a result of centripetal acceleration? the speed decreases in the same direction. the speed increases in the same direction. the direction changes along with the speed. the direction changes but not the speed.

When we look at centripetal acceleration, the acceleration is a change in velocity. Since velocity is a vector, when we change direction, we have an acceleration even if the speed is not changing. An object's motion changes direction but does not change in speed when looking at centripetal acceleration.

Neptune is the eighth planet from the sun. it was the first planet to get its existence predicted by  mathematical calculations  before it was actually seen through a telescope on sept. 23, 1846. irregularities in the orbit of  uranus  led french astronomer alexis bouvard to suggest that the gravitational pull from another celestial body might be responsible. german astronomer johann galle then relied on subsequent calculations to   spot neptune via telescope. previously, astronomer galileo galilei sketched the planet, but he mistook it for a star due to its slow motion. in accordance with all the other planets seen in the sky, this new world was given a name from greek and roman mythology — neptune, the roman god of the sea.