planetary scientist

(uncommon) Those things that are planets; the state of being a planet.

plural of planetologist

(astronomy) A nebulosity surrounding a dying red giant, consisting of material expelled by the star.

Of or pertaining to planetology.

plural of planetary ring

Alternative spelling of extraplanetary

plural of planetoid

(astronomy) The branch of astronomy concerned with the description of the physical features of planets

Of or pertaining to planetography / Describing a coordinate based on the direction of a perpendicular at a point on a planet's surface