mars
The planet that moves through the background of stars most slowly is Mercury. This is because Mercury is the closest planet to the Sun and has a shorter orbit period than the other planets, resulting in a slower apparent motion against the background of stars as seen from Earth.
All of them.
The planet that has the slowest orbit would be Neptune due to the fact that is is furthest away from the sun. However, if you want to count dwarf planets, then Eris would be the slowest.
pluto... :)
Jupiter
A slug moves slowly and so does a snail
A planet's predominant movement (NOT the daily movement related to Earth's rotation, but the apparent movement compared to the background stars) is from west to east. If a planet moves in this direction it is said to be "prograde", if it moves in the opposite direction, it is said to be "retrograde".
Of the major planets, Neptune. The speed of planets in their orbits is directly related to their distance from the sun. The farther a planet is from the Sun, the slower its orbital speed.
Slowly. Their tinly little fins will flap like crazy, but the seahorse will move slowly through the water.
Molecules in a material move slowly through thermal energy. As temperature increases, the kinetic energy of the molecules increases, causing them to move faster.
Mercury moves most slowly around its orbit among all the planets in our solar system. It has the shortest orbital period (88 Earth days) and moves at a slower average speed compared to other planets like Venus, Earth, and Mars.
Neptune moves more slowly than Earth. The farther a planet is from the Sun, the longer its orbit. But the lesser gravity of the Sun at longer distances means that the planets also do not need to move as rapidly in their orbits. A planet farther from the Sun moves more slowly than one closer to the Sun.