Existing or occurring between planets. A planet (from the Greek πλανήτης, planetes or wanderers) is a body of considerable mass that orbits a star and that produces very little or no energy through nuclear fusion. ...
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.
The temperature of the interplanetary medium is approximately 10,000 K, and its density is very low at about 5 particles per cm³ in the vicinity of the Earth; it decreases with increasing distance from the sun, in proportion with the inverse square of the distance.
The plasma in the interplanetary medium is also responsible for the strength of the Sun's magenetic field at the orbit of the Earth being over 100 times greater than originally anticipated.
New interplanetary superpowers, the Orbital States, Mars, and increasingly, the Belt and the Gas Giant Moons arose at the same time as the old superpowers of Earth continue to disintegrate.
Interplanetary age - the vanguard of humanity leaves the Earth to colonization of the solar system, tweaked and superior humans, and animal provolves, the rise of Cis-Lunar, Martian, and Jovian superpowers, entrenched inequality of rich and poor, the colonization of the nearest stars.
Interplanetary Dark Age (Nanoswarm period) - This is a dark age in the Sol System only - although since Solsys culture dominated the early federation, the name stuck despite the error.