We say that a planet is in conjunction with another planet or object when the two are positioned in line, or very close, as viewed from Earth. Such alignments are of no real astronomical importance, except that a planet in conjunction with the Sun is not visible in the night sky. Planets in conjunction with each other, or with the Moon, make an attractive spectacle.
As inner planets, Mercury and Venus have inferior and superior solar conjunctions. Inferior conjunction is when a planet lies between Earth and the Sun and superior conjunction is when a planet lies behind the Sun. The outer planets may only have superior conjunctions with the Sun.
Below is a table of the planetary conjunctions.
