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Scholz's star

(Encyclopedia)Scholz's star, dim binary star system, consisting of a red dwarf and brown dwarf, in the constellation Monoceros, apparent magnitude 18.3. The red dwarf is a tiny star, with less than ten percent the ...

solar time

(Encyclopedia)solar time, time defined by the position of the sun. The solar day is the time it takes for the sun to return to the same meridian in the sky. Local solar time is measured by a sundial. When the cente...

Kuiper, Gerard Peter

(Encyclopedia)Kuiper, Gerard Peter or Gerrit Pieter gĕrˈĭt pēˈtər kīˈpər [key], 1905–73, American astronomer, b. the Netherlands. Kuiper is considered to be the father of modern planetary science for his...

SETI

(Encyclopedia)SETI sĕtˈē [key] [Search for ExtraTerrestrial Intelligence], name given to a series of independent programs to detect radio signals from civilizations beyond the solar system. Modern SETI efforts c...

Lamont, Johann von

(Encyclopedia)Lamont, Johann von yōˈhän fən läˈmônt [key], 1805–79, Scottish-German astronomer and magnetician, b. Scotland. In 1817 he went to Ratisbon to study at the seminary. He remained in Germany to ...

day

(Encyclopedia)day, period of time for the earth to rotate once on its axis. The ordinary day, or solar day, is measured relative to the sun, being the time between successive passages of the sun over a stationary o...

sunstone

(Encyclopedia)sunstone. 1 Crystal mineral thought by some to have been used by the Vikings as an aid to navigation, especially in conditions of low visibility due to clouds or fog when the position of the sun was u...

perihelion

(Encyclopedia)perihelion pĕrˌəhēˈlēən [key], point nearest the sun in the orbit of a body about the sun. See apsis. ...

heliotrope

(Encyclopedia)heliotrope hēˈlēətrōpˌ [key] [Gr.,=sun-turning] or turnsole, name for any plant that turns to face the sun, especially members of the genus Heliotropium of the family Boraginaceae. The garden he...

solar wind

(Encyclopedia)solar wind, stream of ionized hydrogen—protons and electrons—with an 8% component of helium ions and trace amounts of heavier ions that radiates outward from the sun at high speeds. The continuous...