Nereid has a long orbital period, but there are others with longer periods, for example Phoebe, a moon of Saturn.
If you count all the moons, including the really small ones, the answer is "Neso"
the outermost moon of Neptune. That has an orbital period of over 25 Earth years.
Neptune, since it is further away from the sun and since Pluto is not a planet anymore. According to Kepler's third Law of Planetary motion (The Harmonic Law). The more distance a planet's orbit is from the sun, the longer it's year.
Neptune is the gas giant furthest from the Sun and Kepler's third law tells us that the period of revolution of a planet around the sun increases as distance from the Sun increases. It does not matter if the planet is a gas giant or not. The law says period depends on distance and not mass.
It takes 60,190 days for Neptune to orbit the Sun which is about 165 Earth years. For that matter, one Neptune Year is 89,666 Neptune days.
If Pluto was still a planet, it would get the record for the longest year since it is, on the average, further than the other planets.
Pluto has an orbital period of 248 earth years. Since Pluto was discovered in 1930, it has only completed about 1/3 of a revolution.
Since Pluto is no longer considered a planet that title goes to Neptune, with an orbital period of 165 years.
Pluto! If it's still a planet, I think it is. Next in line is Neptune.
Neptune, the farthest planet from the Sun
venus
If you mean revolution on it axis (spin/day length) rather than orbital period, then the answer is the planet Mercury, where time between sunrises is roughly 176 Earth days.
''Mercury (shortest),''Neptune (longest)
The difference between the rotation and revoulution is that rotation is the spiinning of the planet on its axis and revoulution is the orbiting of the planet around the sun.
Jupiter has the smallest period of rotation. It is about 9 hours 50 minutes.
Neptune.
Pluto has the longest REVOLUTION period Venus has the longest ROTATION period
The planet with the largest (or longest) rotation period is Venus, at 243 Earth days (retrograde, meaning clockwise, instead of counterclockwise like the Earth).
Venus
venus
There is no such planet known. The planet with the longest rotation period is Venus. That rotates in about 243 Earth days.
Venus
If you count Pluto as a planet its Pluto :D
If you mean revolution on it axis (spin/day length) rather than orbital period, then the answer is the planet Mercury, where time between sunrises is roughly 176 Earth days.
chocolate pie... but that was 3 years ago...
The difference between the rotation and revoulution is that rotation is the spiinning of the planet on its axis and revoulution is the orbiting of the planet around the sun.
''Mercury (shortest),''Neptune (longest)
The difference between the rotation and revoulution is that rotation is the spiinning of the planet on its axis and revoulution is the orbiting of the planet around the sun.