yes
Yes, Neptune has 13 moons.In order of orbital distance from Neptune, they are :NaiadThalassaDespinaGalateaLarisaaProteusTritonNereidHalimedeSaoLaomedeiaPsamatheNeso
Asteroids, comets, minor or dwarf planets, and even some artificial spacecraft orbit the Sun but are not considered true planets.
The distances between planets depend on where in their orbit they are.
The terms "inferior planet" and "superior planet" were originally used in the geocentric cosmology of Claudius Ptolemy to differentiate those planets (Mercury and Venus) that were between the stationary Earth and the orbiting Sun from those planets (Mars, Jupiter, and Saturn), which lay beyond the Sun's orbit.The terms are now used with the heliocentric model."Inferior Planets" have orbits closer to the Sun than the Earth's orbit.They are Mercury and Venus.The "Superior Planets" have orbits outside the Earth's orbit.They are Mars,Jupiter, Saturn, Uranus and Neptune.So, the meaning is slightly different from "Inner Planets" and "Outer Planets".
They are approximately spherical.They orbit the sun.
No, the statement is not always true. While some planets, like Jupiter and Saturn, have numerous moons, not all planets in our solar system have 12 moons. Some planets, like Earth and Mars, have fewer moons, while others have none at all.
Planets further out from the sun have a larger orbit to travel around, which takes more time. This is because their orbital path is longer, meaning they move at a slower average speed compared to planets closer to the sun. This results in different orbital periods for different planets.
there is no true relationship between distance from the sun and orbit time as some planets go revolves at a different velocity.
Of what we have found most are the size of Jupiter or larger. But we know many more extrasolar planets exist that we simply cannot detect. If we were to draw hypotheses on what planets are most abundant they would either be similar to dwarf planets. Or, if the reader does not view dwarf planets as true planets then planets the size of ones in the terrestrial zone like: Mercury, Venus, or Earth. Are probably the most abundant.
No, gravity holds planets in orbit around the sun because the sun's gravity pulls on them. This gravitational force between the sun and planets keeps them in their respective orbits. The force between planets themselves is much smaller and mainly affects their interactions with each other rather than their orbits around the sun.
Titan and Ganymede are both larger (but less massive) than Mercury and could certainly be called planets if they qualified under the IAU criteria. The conditions include a requirement that they orbit the Sun, and not Saturn or Jupiter, respectively, which currently make them moons, not true planets. They would further need to have cleared their orbits if they were in solar orbit.
Planets are large celestial bodies that orbit a star and have cleared their orbit of other objects, while asteroids are smaller rocky or metallic bodies that also orbit a star but have not cleared their orbit. Planets are typically round due to their gravitational pull, while asteroids can have irregular shapes.