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Ra,symbol for the element radiumradium
[Lat. radius=ray], radioactive metallic chemical element; symbol Ra; at. no. 88; mass number of most stable isotope 226; m.p. 700°C;; b.p. 1,140°C;; sp. gr. about 6.0; valence +2. Radium is a lustrous white radioactive metal.
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Re(rā), in Egyptian religionEgyptian religion,
the religious beliefs of the ancient inhabitants of Egypt. Information concerning ancient Egyptian religion is abundant but unsatisfactory. Only certain parts of Egyptian religious life and thought are known; whole periods remain in the dark.
..... Click the link for more information. , sun god, one of the most important gods of ancient Egypt. Ra was chief of the cosmic deities and was sometimes called the creator and father of all things. Early Egyptian kings alleged descent from him and added his name to their own royal titles. Ra had several manifestations, the most common being those of the hawk and the lion. He was depicted as sailing across the sky in a celestial barge during the day and battling the forces of evil and darkness by night. Various other Egyptian gods were frequently identified with him, such as Amon and Atum.
RAAbbrev. for right ascension.
the name of a boat built, like ancient Egyptian vessels, out of Ethiopian papyrus, aboard which the Norwegian ethnologist and explorer T. Heyerdahl attempted to cross the Atlantic Ocean in 1969. The attempt was unsuccessful owing to defects in the construction of the boat. Heyerdahl’s aim was to prove that the ancient Egyptians could have been in contact with the early inhabitants of America.
In 1970, Heyerdahl undertook a new expedition with seven companions. Ra II, which left Safi, Morocco, on May 17, reached the island of Barbados in the Antilles on July 12. Among the crew members was the Soviet physician Iu. A. Senkevich.