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Pleiades, in astronomy

(Encyclopedia)Pleiades plēˈədēz, plīˈ– [key], in astronomy, famous open star cluster in the constellation Taurus; cataloged as M45. The cluster consists of some 500 stars, has a diameter of 35 light-years, ...

plum, in botany

(Encyclopedia)plum, common name for a tree of any of many species of the genus Prunus of the family Rosaceae (rose family) and for its fruit, a drupe. The plum is generally cultivated in the temperate zones, though...

Pluto, in astronomy

(Encyclopedia)Pluto, in astronomy, a dwarf planet and the first Kuiper belt, or transneptunian, object (see comet) to be discovered (1930) by astronomers. Pluto has an elliptical orbit usually lying beyond that of ...

pod, in botany

(Encyclopedia)pod or legume, dehiscent fruit of a member of the family Leguminosae (pulse family). At maturity the pod splits along its two seams and releases the enclosed seeds. ...

rust, in botany

(Encyclopedia)rust, in botany, name for various parasitic fungi of the order Uredinales and for the diseases of plants that they cause. Rusts form reddish patches of spores on the host plant. About 7,000 species ar...

rye, in botany

(Encyclopedia)rye, cereal grain of the family Poaceae (grass family). The grain, Secale cereale, is important chiefly in Central and N Europe. It seems to have been domesticated later than wheat and other staple gr...

phase, in astronomy

(Encyclopedia)CE5 Phases of the moon phase, in astronomy, the measure of how much of the illuminated surface of a planet or satellite can be seen from a point at a distance from that body; the term is most ofte...

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