No planets have a 29 earth-day year. The planet with the shortest year is Mercury, 'cause it's closest to the sun and has the highest orbital speed. It takes Mercury just a little bit short of 88 earth-days to complete a trip about the sun. In comparison, the earth's only natural satellite, the moon, takes about 27.32 days to orbit our planet.
Every 4 years February has 29 days!
The dwarf planet Pluto is the planet with a year 248 earth years long.
The dwarf planet Haumea is the planet with a year 280 earth years long.
The dwarf planet Makemake is the planet with a year 310 earth years long.
The dwarf planet, Pluto, has a year of 247.9 Earth years.
As of 2013, Pluto has been classed as a dwarf planet for 7 years.
The planet Uranus. Its year is about 84 of our years.
The smallest planet in our solar system 5 years ago was Mercury. Mercury is the smallest planet and the closest to the Sun in our solar system.
81 years ago, the PLANET Pluto was discovered. It wasn't reclassified as a "dwarf planet" until 2006.
Planet Gliese
The planet with a summer that last for 21 years is Uranus. All of the seasons on the planet last for this amount of time.
The planet you are referring to is the dwarf planet Pluto, which takes just over 248 years to orbit the Sun.