if a planet orbits farther from the sun, is it slower or does it orbit the same speed as earth does, but ...?

Question

their orbit is longer?

traveling speed slower or same speed as earth but orbit is longer(just repeating)

Answer 1

Actually, neither. The time it takes a planet to make one revolution around the sun is called a year and years are different from planet to planet. Since planets are neither in a fixed rotation with other planets or the sun, the length of their years are also not fixed with regards to eachother. So, not only do different planet travel different distances in their orbits, but they also travel in those orbits at different speeds.

For instance, as you may know, the horses on the inside ring of a typical merry-go-round actually travel at a slower speed than those on the outside ring. But if each of these rings were actually independent of eachother, they could travel around the sun at different speeds as well as travelling different lengths, which is what planetary rotation does.

Answer 2

No, the orbital speed is a direct function of the mass of the object being orbited and the distance from that object. In the case of the Sun, an orbit farther out than the Earth would have to be slower.

Answer 3

The planet in the orbit farther from the Sun actually moves slower. Fewer miles per hour. Plus it also has to go farther, so the time taken to complete one orbit is even longer because of that.

Answer 4

Mostly, the bigger the orbit, the slower the speed.

The Sun and all the planets orbit around the "barycenter" of the solar system. The distance and speed of all of them is constantly changing; here they are for Oct 19, 2007, at 00:00 UTC. Notice that the speed is lower the further away the planet is, except for Pluto which is moving faster than Neptune even though it is further away. Notice also that these speeds are a lot different than the average speed for a planet over the course of its year.

The median speed in this list is 1,112,291 km /day for Jupiter.

Ceres, Pluto, and Eris are "dwarf planets".

Planet / Distance (AU) / Speed (km / day):

Sun 0.0049 / 959
Mercury 0.35 / 4,546,037
Venus 0.73 / 3,034,412
Earth 1.00 / 2,583,782
Mars 1.50 / 2,130,890
Ceres 2.84 / 1,511,727
Jupiter 5.27 / 1,112,291
Saturn 9.25 / 859,689
Uranus 20.09 / 560,703
Neptune 30.04 / 470,109
Pluto 31.35 / 505,679
Eris 96.80 / 198,145

Answer 5

If it is further away, it's orbit takes longer and it's actual speed is slower. if Neptune (for example) traveled the same speed as the Earth, the sun's gravity at that distance would not be strong enough to keep it in orbit.

Answer 6

The orbital velocity is lower as you get further from the Sun. A lower velocity coupled with a longer path stacks up to make a much longer solar year.

Earth's speed around the sun averages about 30km/sec

Jupiter's is about 13km/sec. Jupiter is still pretty close to the sun compared with Neptune and Pluto.

A thought experiment that helps with this - think of highly elliptical orbits. (like comets) The objects speed up as they approach the sun, and slow back down as they get further away. Nothing's changing the total energy of the body, it's just being converted back and forth between potential energy and kinetic energy.