An impeller (also written as impellor or impellar) is a rotor used to increase (or decrease in case of turbines) the pressure and flow of a fluid. An impeller for a dam turbine generator.
The smallest planet in the Solar System is Mercury (the biggest planet is Jupiter). For the longest time, the smallest planet was considered to be Pluto, but now Pluto isnât a planet any more, so weâre back to Mercury.Mercury measures 4879 km along its equator.Just for comparison, Earth is 12,742 km across.So Mercury is only 38% the diameter of Earth.or the longest time, the smallest planet was considered to be Pluto, but now Pluto isnât a planet any more, so weâre back to Mercury. Mercury measures 4879 km along its equator. Just for comparison, Earth is 12,742 km across.
These planets can be divided into terrestrial planets (Mercury, Venus, Earth, and Mars) and gaseous planets (Jupiter, Saturn, Uranus, and Neptune). The smallest planet is Mercury, which is closest to the sun. Venus is the second from the sun. It is similar to Earth in size and mass, but it is so hot, that lead would melt on its surface. The third from the sun is Earth. Its distance from the sun allows it to have liquid water and an atmosphere suitable for life.