Association of British Scrabble Players

Science & Tech > Physics > Astronomy


Now updated for CSW19. New words, if any, and new inflections of existing words, are shown in red.


achondrite a stony meteorite without rounded grains.
achondritic of or like an achondrite, a stony meteorite without rounded grains.
acronically (Adv.) ACRONICAL, occurring at nightfall.
almacantar (Arabic) a circle of altitude, parallel to the horizon.
almagest (Arabic) a textbook or handbook, esp dealing with astronomy.
almucantar (Arabic) a circle of altitude, parallel to the horizon.
analemma (Greek) the figure-8 on a map showing the sun's seasonal course > ANALEMMAS or ANALEMMATA.
anomalistic anomalous.
ansa (Lat.) part of Saturn's rings >ANSAE or ANSAS.
antipodal situated at the opposite side of the earth or moon; diametrically opposed; (noun) in flowering plants, a type of cell.
antisolar opposite to the sun, said of the point in the heavens 180° distant from the sun.
aphelian relating to an aphelion, the point when the earth is farthest from the sun during its annual orbit.
aphelion (Greek) the point when the earth is farthest from the sun during its annual orbit > APHELIA or APHELIONS.
apoapsis (Lat.) the high point in an orbit > APOAPSES.
apocynthion the point at which a spacecraft in lunar orbit is furthest from the moon.
apogaeic relating to an apogee, the outermost point in an orbit.
apogeal relating to an apogee, the outermost point in an orbit.
apogean relating to an apogee, the outermost point in an orbit.
apogee the outermost point in an orbit.
apogeic relating to an apogee, the outermost point in an orbit.
apolune the point in the orbit of a body revolving round the moon that is farthest from the centre of the moon.
appulse the close approach of a planet or asteroid to a star without the occurrence of an eclipse.
appulsive relating to an appulse, the close approach of a planet or asteroid to a star without the occurrence of an eclipse.
appulsively (Adv.) APPULSIVE, relating to an appulse, the close approach of a planet or asteroid to a star without the occurrence of an eclipse.
apsis (Lat.) the point at which a heavenly body is most or least distant from the centre of attraction > APSIDES.
archeoastronomy the scientific study of the beliefs and practices concerning astronomy that existed in ancient and prehistoric civilizations.
areocentric of a coordiante system based on the planet Mars.
areographic relating to areography, the description of the physical features of the planet Mars.
areography description of the physical features of the planet Mars.
areology the study of Mars. [From Ares, the Greek equivalent of Mars in classical mythology) + logy (study)].
ascendant rising (noun) the part of the ecliptic just risen or about to rise above the horizon
ascendantly (Adv.) ASCENDANT.
ascendent the part of the ecliptic just risen or about to rise above the horizon.
asterism a constellation of stars; a group of asterisks.
asteroid a type of celestial body.
asteroidal of or pertaining to an asteroid, or to the asteroids.
astrally (Adv.) ASTRAL, related to stars.
astrobleme the wound left by a meteorite strike.
astrohatch a domed window in an aircraft for astronomical observations.
astrometry the art of making measurements among the stars, or of determining their relative magnitudes.
astronaut a person engaged in space travel.
astronautic relating to astronautics.
astronautical relating to astronautics.
astronomer a person who is skilled in astronomy or who makes observations of celestial phenomena.
astronomic related to astronomy.
astronomical related to astronomy.
astronomically (Adv.) ASTRONOMICAL, of or relating to astronomy.
astronomise to study astronomy.
astronomize to study astronomy.
astronomy the study of the celestial bodies and the heavens in all scientific aspects.
azimuth (Arabic) the angle a celestial object makes from due north, when measured in an eastwards direction along the horizon.
azimuthal of or pertaining to the azimuth.
azimuthally (Adv.) AZIMUTHAL, of or pertaining to the azimuth.
biosatellite an artificial satellite containing living organisms to be studied during flight.
blazar a type of active galaxy that is a more energetic source of radiation than a quasar.
blueshift a shift of the spectrum towards the blue.
bolide a large meteor that bursts; a fireball.
canicular pertaining to the dog star, or the dog days of summer.
capcom a ground-based NASA communicator who maintains contact with astronauts during space missions.
cepheid a star of a type having regular cycles of brightness which can be used to deduce their distances.
chondrite a meteoric stone characterized by the presence of chondrules.
chromosphere the region of the atmosphere of a star between the star's photosphere and its corona.
chromospheric relating to the chromosphere.
circumlunar situated or moving round the moon.
circumsolar situated or moving round the sun.
coelostat an astronomical instrument used to reflect light on to a telescope.
collapsar a black hole.
collimator a telescope arranged and used to determine errors of collimation, both vertical and horizontal.
colure a celestial circle that intersects another at the poles.
coma (Lat.) a spherical cloud of material surrounding the head of a comet.
comal relating to a coma, a spherical cloud of material surrounding the head of a comet.
comet a celestial body.
cometary pertaining to, or resembling, a comet.
cometic relating to a comet.
cometography the description of comets.
cometology the study of comets.
coronagraph an instrument for viewing the corona of the sun.
coronograph a special telescope used to observe prominences and the corona around the edge of the sun.
cosmic of or pertaining to the universe as an ordered system or totality.
cosmical of or pertaining to the universe as an ordered system or totality.
cosmically (Adv.) COSMIC, of or pertaining to the universe as an ordered system or totality.
cosmologic relating to cosmology.
cosmological relating to cosmology.
cosmologically (Adv.) COSMOLOGICAL, relating to cosmology.
cosmologist one who studies cosmology.
cosmology the study of the cosmos.
cosmos (Greek) the world or universe.
cosmosphere an apparatus for showing the position of the earth at any given time with reference to the fixed stars.
coude (Fr.) a reflecting telescope in which one or more plane mirrors reflects the light down the polar axis.
dayside the side of a planet facing the sun.
daystar the planet Venus.
deorbit to come out of an orbit.
discless having no disc; appearing as a point and not expanded into a disk, as the image of a faint star in a telescope.
diskless having no disk; appearing as a point and not expanded into a disk, as the image of a faint star in a telescope.
earthlight the faint light visible on parts of the moon not illuminated by the sun.
earthlike like the planet earth.
earthrise the rising of the earth as seen from the moon.
earthset the setting of the earth as seen from the moon.
earthshine the faint light visible on parts of the moon not illuminated by the sun.
eclipse the total or partial disappearance of a heavenly body by the interposition of another between it and the spectator; (verb) to obscure.
ecliptic an imaginary circle which the sun follows from Earth perspective.
ecliptically (Adv.) ECLIPTIC, like an imaginary circle which the sun follows from Earth perspective.
emersion the act of emerging esp the reappearance of a heavenly body after eclipse or occultation.
ephemeris (Greek) a table giving the positions of celestial bodies at different times > EPHEMERIDES.
ephemerist one who studies the daily motions and positions of the planets.
equant (Lat.) a term in Ptolemy's astronomical system.
evection a lunar inequality, the combined effect of the irregularity of the point of the moon's orbit at which it is nearest to Earth and the alternate increase and decrease of the eccentricity of the moon's orbit.
evectional relating to evection, a lunar inequality.
exoplanet a planet that orbits a star in another solar system.
extragalactic originating or existing outside the Milky Way galaxy.
extrasolar beyond the solar system.
facula (Lat.) an unusually bright spot on the sun's surface.
facular of or pertaining to faculae, groups of small shining spots on the surface of the sun.
galaxy a star system.
geoprobe a space probe for exploring space near the earth.
geostationary of or pertaining to a satellite that travels about the earth's equator at an altitude of at least 35,000 kilometers at a speed matching that of the earth's rotation, thus maintaining a constant relation to points on the earth.
gibbosity the state of being gibbose, of a moon, between half and full.
heliac solar; coincident with that of the sun, or as nearly as could be observed.
heliacal solar; coincident with that of the sun, or as nearly as could be observed.
heliacally (Adv.) HELIACAL, relating to the sun.
heliology the science of the sun.
helioscope an instrument for observing the sun without injury to the eyes.
helioscopic related to a helioscope.
hypernova an exploding star than produces even more energy and light than a supernova.
inerrant unerring, fixed (of a star).
intercrater (of a flat plain on a planet's surface) situated between two large craters.
intergalactic situated in or relating to the spaces between galaxies.
interstellar in the intervals between the stars.
interstellary in the intervals between the stars.
intramercurial within Mercury's orbit.
isophotal relating to an isophote, a line connecting points of equal light intensity from a given source.
isophote a line connecting points of equal light intensity from a given source.
kosmos (Greek) the universe, everything.
loadstar the polestar; one that serves as an inspiration, model or guide.
lodestar the polestar; one that serves as an inspiration, model or guide.
lunanaut one who travels to the moon.
lunar relating to the moon; (noun) a lunar distance.
lunarnaut one who travels to the moon.
lunet a little moon or satellite.
lunisolar relating jointly to the moon and sun.
lunitidal pertaining to tidal movements dependent on the moon.
magnetar a type of neutron star that has a very intense magnetic field.
magnetosphere a region of space surrounding a celestial object that is dominated by the object's magnetic field such that charged particles are trapped in it.
magnetospheric relating to the magnetosphere.
mare a sea on the moon a female horse
marsquake a violent tremor on Mars.
mascon a concentration of dense mass beneath the moon's surface.
metagalactic relating to a metagalaxy.
metagalaxy the whole universe considered as a system of galaxies; any system of galaxies.
meteor a small celestial body that enters the earth's atmosphere.
meteoroid a meteor that has not reached the earth's atmosphere.
meteorous of the nature or appearance of a meteor.
micrometeorite a very small meteorite.
micrometeoritic of or like a micrometeorite.
micrometeoroid a small meteoroid.
moon the satellite of a planet (verb) to spend time idly
moondust soil from the moon.
moonless lacking the light of the moon.
moonlet a small moon.
moonlike resembling the moon.
moonphase a phase of the moon.
moonscape a view of the moon's surface.
moonset the setting of the moon.
multiverse the sum of all universes.
nadir (Arabic) the point of the heavens diametrically opposite to the zenith.
nadiral of or like a nadir, the point of the heavens diametrically opposite to the zenith.
nebula (Lat.) a hazy or indistinct luminous area in the night sky representing a distant cluster of stars.
nebular of or like a nebula, a hazy or indistinct luminous area in the night sky representing a distant cluster of stars.
nebulose like a nebula, cloudy.
nebulous like a nebula, cloudy.
nebulously (Adv.) NEBULOUS, cloudy, vague.
nodical of or pertaining to the nodes, as, the nodical revolutions of the moon.
nonagesimal ninetieth; (noun) the point of the ecliptic 90° from its intersection by the horizon.
nonsolar not solar.
nonstellar not stellar.
nova (Lat.) an exploding star.
novalike like a nova.
orbit the path in which a celestial body moves round another; (verb) to move or revolve around.
orbital relating to an orbit (noun) an orbit
orbitally (Adv.) ORBITAL, relating to an orbit.
orrery an apparatus showing the relative positions and motions of bodies in the solar system by balls moved by wheelwork.
pallasite a class of stony meteorite.
parallax the seeming change of an object's position due to the observer moving.
paraselene a mock moon; bright patch on a lunar halo.
paraselenic relating to the paraselene, a mock moon; a bright patch on a lunar halo.
periapsis the closest point to a central body reached by a body in orbit.
periastron that point, in the real or apparent orbit of one star revolving around another, at which the former is nearest to the latter.
pericenter the point in the path of a body revolving round a centre at which it is nearest to the centre.
pericentre the point in the path of a body revolving round a centre at which it is nearest to the centre.
pericynthion the point at which a spacecraft in lunar orbit is nearest to the moon.
perigeal relating to a perigee, the point of the moon's orbit at which it is nearest the earth.
perigean relating to a perigee, the point of the moon's orbit at which it is nearest the earth.
perigee (Greek) the point of the moon's orbit at which it is nearest the earth.
perihelial relating to the perihelion.
perihelion the point of the orbit of a planet or a comet at which it is nearest to the sun, as opposed to aphelion.
perilune the point in the path of a body orbiting the moon that is nearest to the centre of the moon.
periselenium in an elliptical orbit about the moon, that point which is closest to the moon.
photosphere the sun's luminous envelope.
photospheric relating to the photosphere.
plage a bright area on the sun.
planet a celestial body.
planetary of or pertaining to the planets; (noun) a train of planetary gears.
planetesimal an asteroid or similar tiny celestial body.
planetic of or pertaining to planets.
planetical of or pertaining to planets.
planetlike like a planet.
planetoid a body resembling a planet; an asteroid.
planetoidal like a planetoid.
planetological relating to planetology.
planetologist one who studies planetology.
planetology the study of planets.
planetwide extending throughout or involving an entire planet.
planisphere a sphere projected onto a plane; a map of the heavens.
planispheric relating to the planisphere.
plenilunar of or relating to the full moon.
plerion a supernova remnant emitting radiation from both centre and shell.
plutoid any dwarf planet beyond Neptune.
polestar a guide or director.
protogalaxy a galaxy in its initial state of formation.
protoplanet a planet in its initial state of formation.
protoplanetary of or like a protoplanet.
protostar a condensing mass of gas in the early formation of a star.
pulsar a rapidly rotating neutron star.
quasar a celestial object that resembles a star optically but is inferred to be an extremely remote and immensely powerful source of light and other radiation.
redshift the displacement of the light a receding object emits toward the red end of the spectrum.
redshifted of eg a star, having its light shifted towards the red.
retroengine a small rocket on a spacecraft which is fired to alter its course or slow it down.
rille one of certain narrow, crooked valleys seen, by aid of the telescope, on the surface of the moon.
satelles (Obs.) a satellite.
satellite a body revolving around a planet; (verb) to transmit by satellite.
satellitic of or like a satellite.
selenian lunar.
selenic (Greek) of or relating to the moon.
selenocentric pertaining to moon's centre; having moon as centre.
selenograph a delineation of the moon.
selenographic relating to selenography, the mapping of the moon.
selenographical relating to selenography, the mapping of the moon.
selenography the branch of astronomy dealing with the physical features of the moon.
selenological relating to selenology.
selenologist one who studies the moon.
selenology the study of the moon.
septentriones the seven stars of the Plough, the Great Bear.
shergottite a type of meterorite, composed of solidified lava from celestial bodies other than earth.
sidereal of or relating to the stars; measured by apparent motion of the stars.
sidereally (Adv.) SIDEREAL, of or relating to the stars.
siderolite a meteorite made up partly of stone, partly of iron.
siderostat a mirror, or telescope with a mirror, for reflecting the rays of a star in a constant direction.
siderostatic of or like a siderostat, a mirror, or telescope with a mirror, for reflecting the rays of a star in a constant direction.
skylab an orbiting experimental space station.
skywatch to observe the sky for heavenly bodies or aircraft.
solunar relating to sun and moon.
spacecraft a vehicle or device designed for travel or operation outside the earth's atmosphere.
spacetime time and three-dimensional space regarded as fused in a four-dimensional continuum.
spacewalk an excursion by an astronaut outside his or her craft while in space; (verb) to walk in space.
spacewalker one who walks in space.
spaghettify to make into spaghetti, with particular reference to black holes.
spinar a rapidly spinning galactic body.
sputnik (Russian) an orbiting spacecraft.
stardrift a common proper motion of a number of stars in the same region.
stardust cosmic dust, meteoric matter in fine particles.
stargaze to observe stars.
starnie (Scots) a small star.
starshine the light of stars.
starspot an area of relative darkness on the surface of a star.
stellar relating to stars.
subcluster a group of galaxies within a cluster of galaxies; (verb) to form part of a cluster.
subdwarf a star smaller than a dwarf star.
subsolar directly under the sun, as a point on the earth's surface where the sun is vertically overhead.
sun the star that is the source of light (verb) to expose to the sun's rays
sunlike like or resembling the sun.
sunspot a dark spot on the surface of the sun.
sunspotted showing sunspots.
supercluster a group of gravitationally associated clusters of galaxies.
supergiant a very bright star of enormous size and low density, such as Antares.
supermoon an instance of the moon appearing particularly large in the sky due to its closest approach to the earth (the perigee) coinciding with a full moon.
supernova (Lat.) a very brilliant nova resulting from an explosion which blows the star's material into space, leaving an expanding cloud of gas.
swingby the passing of a spacecraft near a planet to use its gravitational pull.
syzygal related to a syzygy.
syzygetic relating to a syzygy.
syzygetically (Adv.) SYZYGETIC.
syzygial related to a syzygy.
syzygy (Greek) conjunction or opposition.
teinoscope (Obs.) a prism telescope.
terraform to make (another planet) earthlike.
thindown a lessening in the number of atomic particles and cosmic rays passing through the earth's atmosphere.
topocentric Relating to, measured from, or as if observed from a particular point on the earth's surface.
transit the apparent passage of a smaller planet, etc over the disc of a greater; (verb) to pass across or through (something); to traverse.
translunar of or relating to the region beyond the moon's orbit.
translunary of or relating to the region beyond the moon's orbit.
triones the seven stars of the Plough. [L. triones plough-oxen]. N.B. no TRIONE*.
universe the totality of all existing things.
unsphere to draw or remove from its sphere.
uranographer one who maps the constellations.
uranographic relating to uranography, descriptive astronomy and mapping.
uranographical relating to uranography, descriptive astronomy and mapping.
uranographist one who practises uranography, descriptive astronomy and mapping.
uranography descriptive astronomy and mapping.
uranology the study of the heavens.
ursid a meteor.
zenith the highest point.
zenithal of or pertaining to the zenith.