protoplanetary
Before planets form
Protoplanetary describes the early stage of planetary formation, when gas and dust orbit a young star in a flattened disk.
A protoplanetary disk contains the raw material that may eventually clump together to form planets, moons, and asteroids.
The term appears almost exclusively in astronomy and astrophysics.
Growth through external addition
- nebulaInterstellar gas formation
- dustFine settled particles
- gasFormless, expanding substance
- circumstellarSurrounding a star
debris · ring · gap · spiral · temperature · pressure · hydrostatic · equilibrium
Primordial orbiting rock
- embryoOrganism before birth
- asteroidSun-orbiting rocky mass
- cometIcy orbiting body
- meteoroidSmall body in space
chondrite · olivine · pyroxene · moonlet · rubble pile
Uniting into one mass
- condensationVapor turning to liquid
- nucleationInitial cluster formation
- aggregationCombined collection of items
- collapseSudden structural failure
instability · differentiation · cooling · heating · rotation · angular momentum · fragmentation · clumping
Instrument magnifying faraway objects
- HubbleRenowned astronomer's surname
- JWSTInfrared space observatory
- spectroscopyStudy of light-matter interaction
- infraredHeat-bearing electromagnetic waves
submillimeter · imaging · interferometry · transit · coronagraph
accretion
Growth through external addition
circumstellar · debris · ring · gap · spiral · temperature · pressure · hydrostatic · equilibrium · turbulence
planetesimal
Primordial orbiting rock
meteoroid · chondrite · olivine · pyroxene · moonlet · rubble pile
coalescence
Uniting into one mass
- condensationVapor turning to liquid
- nucleationInitial cluster formation
- aggregationCombined collection of items
collapse · instability · differentiation · cooling · heating · rotation · angular momentum · fragmentation · clumping · settling
telescope
Instrument magnifying faraway objects
- HubbleRenowned astronomer's surname
- JWSTInfrared space observatory
- spectroscopyStudy of light-matter interaction
infrared · submillimeter · imaging · interferometry · transit · coronagraph
hydrogen
Simplest atomic element
iron · nickel · carbon · oxygen · nitrogen · volatiles · refractories · organics · isotopes · grains
protoplanetaryformed
Given definite shape
consolidated · coalesced · differentiated · structured · solid
- protoplanetary disksGas and dust orbiting newborn stars
planets, planetary, exoplanet, interplanetary, exoplanets, planetology, protoplanet