number the planets farthest to closest to earth
Mercury and Earth are the two planets closest to Venus.
The inner planets
Venus and Mars are the neighbouring planets of Earth
In the past some planets or protoplanets did collide with each other. Indeed we believe that the Earth/Moon system was created by just such a collision. We can also see comets crashing into planets to this day. However, the solar system is now much more stable and the major planets now orbit the Sun (because of the Sun's gravity), each following their own orbital path. Each orbital path is separated by millions of miles and while the planets' gravities do tug one on another, this is not enough to destabilize the orbits.
Protoplanets are very small planets, about the size of a moon. Astronomers believe these celestial objects are formed during the creation of a solar system.
The inner planets are Mercury, Venus, Earth and Mars. They are the rocky, solid planets of the solar system. Following them are the gas giants Jupiter, Saturn, Uranus and Neptune. Sometimes Uranus and Neptune are called ice giants because while they originated from gaseous materials, they are cold enough to have (probably) an icy or slushy consistency.
number the planets farthest to closest to earth
Mercury and Earth are the two planets closest to Venus.
Mercury is the planet closest to the sun. Next is Venus and then Earth, therefore, they are the closest planets to Mercury.
perihelion is the point in a planets orbit when it is closest to the sun
The first four planets closest to the Sun are the four terrestial planets.
They are rocky planets.
In order, the list of planets closest to the sun (from closest to farthest), Mercury, Venus, Earth, Mars.
Actually, there are 18 known planets in our solar system, as well as two known protoplanets. For a complete list of objects in the solar system, see the related links.
The four inner planets are closest together: Mercury, Venus, Mars & Earth
The inner planets