Without the sun we would have no life forms on earth as the sun provides all the energy o the planet
Neptune. Because it was the farthest planet from the sun. So its orbit's length is long.
All the planets orbit in a perfect circle, so they always stay the same distance from the sun, except Pluto, which is why it is now a "Dwarf Planet".
Asteroids orbit the sun. Moons orbit planets and planets orbit the sun. So you could say the moons orbit the sun. However, moons are kept in their orbits by the gravity of their planet and planets are kept in orbit by the gravity of the sun. So in that sense, moons do not orbit the sun.
U answer
Each planet stays in its orbit because it is being pulled constantly by the Sun's gravity. The planet does not fall into the Sun because it has a velocity taking it along its orbit, so the effect of gravity is only to make the planet's path curve towards the Sun all the time.
Aphelion is the point in a planet's orbit where it is furthest from the Sun. So each planet has exactly one of them.
The comets in our Solar System orbit our Sun. Presumably, a comet could be trapped by a planet, so that it orbits that planet; and presumably, there are also comets around other stars.
Neptune takes approximately 165 years to orbit the sun, while the planet Uranus has an orbital period of about 84 years. Jupiter, on the other hand, takes around 12 years to complete one orbit around the sun.
No planet, under the 2006 IAU definition of a planet, takes 557 Earth years to orbit the Sun. Perhaps you are talking about dwarf planets. If so, please restate the question.
Pluto - though its no longer classed as a planet, more a dwarf planet. For 20 years of its 246 year orbit, it is actually closer to the sun than Neptune
As discovered by Johannes Kepler, the closer a planet is to the sun, the faster it's orbit becomes. As you might expect Mercury completes it's orbit (year) in the fastest time, and each outer planet does so progressively slower.
Mercury is the planet often hidden in the sun's glare due to its close proximity to the sun. Its orbit lies within Earth's orbit, so it is sometimes difficult to observe it in the bright sunlight.