The minor planet Pluto has an orbit which is inclined to the plane of the ecliptic. It is also a highly eccentric ellipse, causing it sometimes to pass inside the orbit of Neptune.
You are thinking of Pluto. Pluto is now designated a minor planet.
The strange things are :1) Its orbit is inclined at a large angle to the plane that the major planets orbit in. There are several other small planetoids (plutoids) with similarly inclined orbits.2) There is a very large difference between its least and greatest distance from the Sun. This is referred to as a highly eccentric or highly elliptic orbit.
Triton orbits Neptune in the opposite direction from all of Neptune's other moons and has a highly inclined orbit.
in some parts of its orbit it is much closer to the Sun than in other parts.
its axis of rotation inclined 45 degrees to the plane of its orbit around the sun
A dwarf planet located in the Kuiper Belt, beyond the orbit of Neptune. It was discovered in 2007 and is the fifth-largest known trans-Neptunian object. Gonggong has a highly eccentric and inclined orbit and ranges from 34 to 101 astronomical units from the Sun. It has a diameter of about 1,230 km and is named after a Chinese water god.
Mercury isthe innermost planet,it is the smallest planet,it has the most eccentric orbit ,its own axis is the least inclined to the plane of its orbit (around 0.01 degrees).
It deviates from a perfect circle by a considerable amount.
Pluto has an eccentric and highly inclined orbit that takes it from 2,757,000,000 to 4,543,000,000 miles from the Sun.
Any time a planet has rings they will be aligned with the planet's equator. Uranus' axis is highly tilted such that its rings are almost perpendicular to its orbit.
Comets don't orbit a planet, they orbit the sun.