Interplanetary Medium

The interplanetary medium is the material which fills the solar system and through which all the larger solar system bodies such as planets, asteroids and comets move.
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Noun
1. interplanetary space including forms of energy and gas and dust
(hypernym) interplanetary space
(part-holonym) solar system
(part-meronym) interplanetary dust

The diffuse matter found between the planets in the solar system. Dust is present as fragments from collisions in the asteroid belt and also as dust from comets which break up during their passage through the inner solar system. Charged particles are provided by the Sun in the form of the solar wind. There are also neutral gas atoms present which are destroyed close to the Sun but are replenished from the interstellar medium.