The question says that there is an object that's in the solar system that's outside the solar system
for half the time. That's a lot like the statement that states: "This statement is false."
Jupiter is an outside planet. It is located beyond the orbit of Mars, making it one of the outermost planets in our solar system.
Pluto
You haven't said what exactly Mars may be inside or outside of; certainly it is inside our solar system. It is farther from the sun than the planet Earth and therefore it could be described as being outside the Earth's orbit. Comment: Mars is called an "inner planet", of course. Perhaps that helps.
Pluto comes inside Neptune's orbit for part of its rotation. Pluto is no longer considered a planet though (it is considered a dwarf planet). None of the current eight planets in our solar system have orbits that cross each other.
Venus is an inferior planet i.e.its orbit is inside the earth's orbit. It does not have a moon It rotates from east to west. Jupiter is a superior planet i.e.its orbit is outside the earth's orbit. It has 63 moons. It rotates from west to east.
Yes.
As of 6 December 2016, there are 3,545 known planets outside the solar system. These orbit 2,660 different stars.
Planets do not orbit the solar system: they orbit the sun and remain inside the solar system.Planetary motion can be calculated from Kepler's laws.
The outermost planet in our solar system, Neptune, is often referred to as the eighth planet. When Pluto was considered a planet (prior to 2006) during its orbit it would cross inside the orbit of Neptune making the latter the outermost planet.
All eight of them, plus (sometimes) the dwarf planet Pluto which has an orbit that brings it inside and outside the orbit of Neptune.
inside
pluto