nonluminous
Gives no light
Nonluminous describes something that produces no light of its own.
The moon is nonluminous—it only reflects sunlight.
The term appears in astronomy and physics to distinguish objects that emit light (stars, flames) from those that don't: nonluminous matter, nonluminous celestial bodies.
Dark matter is sometimes described as nonluminous because it neither emits nor absorbs light.
Light blocked by object
- eclipseCelestial body blocks another
- twilightLight after sunset
- midnightTwelve o'clock at night
- moonlessLacking lunar presence
starless · blackout · void · abyss · pitch · tenebrous · crepuscular · gloaming
Lacking vertical variation
- eggshellBrittle ovum casing
- satinGlossy-surfaced woven cloth
- unreflectiveNot given to self-examination
- unshinyNot reflecting light
drab · subdued · lackluster · tarnished · lusterless · unpolished · unglazed · brushed
Impossible to notice
- hiddenKept out of sight
- camouflagedVisually hidden by coloring
- concealedMade invisible deliberately
- obscuredMade hard to perceive
shrouded · imperceptible · latent · unseen · indiscernible · unobservable · stealth · passive
Perfect thermal emitter
- absorptionProcess of taking in
- infraredHeat-bearing electromagnetic waves
- thermalPertaining to warmth
- radiationEnergy propagation through space
heat · spectrum · wavelength · emission · photon · energy · opaque · nonreflective
shadow
Light blocked by object
moonless · starless · blackout · void · abyss · pitch · tenebrous · crepuscular · gloaming · nocturnal
flat
Lacking vertical variation
- eggshellBrittle ovum casing
- satinGlossy-surfaced woven cloth
- unreflectiveNot given to self-examination
unshiny · drab · subdued · lackluster · tarnished · lusterless · unpolished · unglazed · brushed · textured
undetectable
Impossible to notice
- hiddenKept out of sight
- camouflagedVisually hidden by coloring
- concealedMade invisible deliberately
obscured · shrouded · imperceptible · latent · unseen · indiscernible · unobservable · stealth · passive · dormant
blackbody
Perfect thermal emitter
- absorptionProcess of taking in
- infraredHeat-bearing electromagnetic waves
- thermalPertaining to warmth
radiation · heat · spectrum · wavelength · emission · photon · energy · opaque · nonreflective · dark matter
nonluminousluminous
Emitting or reflecting light
glowing · radiant · incandescent · light-emitting · phosphorescent
illuminate, luminous, illumination, elucidate, luminary, luminosity, luminescent, luminescence, illumine