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sea star

(Encyclopedia)sea star, also called starfish, echinoderm of the class Asteroidae, common in tide pools. Sea stars vary in size from under 1⁄2 in. (1.3 cm) to over 3 ft (90 cm) in diameter. They are commonly dull ...

feather star

(Encyclopedia)feather star, common name of a class of echinoderms that, as juveniles, are attached to the sea bottom by a stalk with rootlike branches; the mouth side faces upward. In the adult stage they break awa...

star

(Encyclopedia)star, hot incandescent sphere of gas, held together by its own gravitation, and emitting light and other forms of electromagnetic radiation whose ultimate source is nuclear energy. The universe co...

sea

(Encyclopedia)sea, term used as synonymous with ocean, or a subdivision of an ocean (Caribbean Sea, Yellow Sea), or erroneously designating a large salt lake (Caspian Sea, Dead Sea, Aral Sea). ...

dwarf star

(Encyclopedia)dwarf star: see white dwarf.

Dog Star

(Encyclopedia)Dog Star: see Sirius.

double star

(Encyclopedia)double star: see binary star.

circumpolar star

(Encyclopedia)circumpolar star, star whose diurnal circle lies completely above or completely below an observer's horizon. A star whose diurnal circle lies above the horizon never sets, even though it cannot be see...

evening star

(Encyclopedia)evening star or morning star, planet that becomes visible in the western sky shortly after sunset or in the eastern sky shortly before sunrise. It can usually be seen in twilight, when it is too light...

failed star

(Encyclopedia)failed star: see brown dwarf.