Why do some planets have longer years then others?

Answer 1

a planets year is determined by how long it takes the planet to circle its sun. As a general rule the farther the planet is from its sun the longer its year will be.

Answer 2

because the further away from the sun a planet is the longer the year

this happens because said planet is further or closer to the sun, therefore occupying an extended or shortened amount time to complete its rotation around the sun.

Answer 3

The length of a day, or even a year differ for each planet because the length of the orbital path around the Sun varies in length. For one planet, it may take 365 days for the planet to revolve around the Sun whereas another planet could take 472 days.

Edit : That's fine for the "year" which is the time to orbit the Sun.

How about the "day", though? There are two main definitions of a

day in astronomy :

1) The "sidereal day". That's the time for the

planet to spin once. That doesn't depend on

the length of the orbit.

2) The "Solar Day." That's the time the Sun

takes to complete its apparent daily journey,

noon to noon, around the sky. This time does

depend on both the spin and the orbit of the

planet.

Answer 4

The length of the year is determined by the planet's solar orbit. The further out the orbit, the longer the year.

Lengths of days are determined by rotational velocity. Mercury is locked in a tidal resonance with the sun, which governs the length of its day (a particular fraction of the length of its year). Venus barely rotates, so the length of its day is 243 times that of ours. The day on Mars is almost as long as ours, in fact just a little bit longer. Jupiter, big as it is, rotates very fast, about once every 10 hours. So its day is less than half the length of ours.

Answer 5

Year length is literally derived from how long it takes a planet to revolve around

the parent star once, in our case it takes the earth 365.24 days to revolve

around the sun, which is also why we have a leap year. Every 4 years we have

an extra day in the year to catch up with the solar calender. Therefore other

planets at a greater distance to the sun then the earth would have a longer

year. This would include Mars, Jupiter, Saturn, Uranus, and Neptune. Also

planets closer in would have a shorter year then the earth these planets would

be Mercury and Venus.

And now, to answer the question: Because that's how gravity works.

If you take Newton's formula for gravitational force, and if you have enough

calculus an geometry to massage Newton's formula for a while and look at it

from different angles, the formula predicts a lot of things about gravitational

orbits that can be confirmed just by observing the planets. One of the things

it accurately predicts is that a planet farther from the sun will take longer to

revolve around the sun ... not only because it has farther to go, but also

because it moves slower in its orbit. The actual relationship for all the orbits

around one star is:

(time for one revolution)2 / (average distance from the star)3

is the same number for every orbiting body in the same system.

Answer 6

What we describe as our year is the time taken for the Earth to travel around the sun once (365 and one quarter days). This circle around the sun is called the Earth's orbit. Different planets have different orbitals depending on the distance they are from the sun. Eg, mercury has the shortest orbital as it is so close. (The earth orbits the sun beacuase of gravity, which is the force between 2 large objects. The planets and sun are pulled towards each other but as the earth travels towards the sun, the curvature of the sun bends and the earth travels around it. We are continually travelling or, i suppose, falling towards the sun. One day, we could theoretically get there as we are gradually getting closer. Cool, huh?)

Answer 7

a year is defined by how long a planet takes to go around the sun. different planets have different years because some take longer to orbit the sun than others

This is due to the rotation around the the Sun. The Earth complete its rotation in 365.55 days, however Pluto (Dwarf Planet) complete its rotation in 365 years.

Answer 8

The further a planet is away from the sun, the longer it takes to orbit. Mars takes 1.8 years to orbit the sun. Jupiter requires 12 earth years, Saturn 30 earth years, Uranus 84 earth years, and Neptune 165 earth years.

The KBO dwarf planet Pluto requires about 250 earth years to make a single orbit of the sun.

Answer 9

A day is when a planet makes one full rotation on its axis.

A year is when a planet makes one full circuit around the sun.

The reason that each planet has a day and a year of different lengths are because each planet moves at a different speed. The planets which rotate slower on their axes have longer days, and the planets which move slower around the sun and are further away from the sun (therefore having a larger circuit to complete, which takes longer) have longer years.

This is why planets have days and years of different lengths.

Answer 10

A year is the time it takes for a planet to revolve around the Sun. Since every planet is at a different distance away from the Sun, the length of one year is different for each planet.