explorer

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Explorer 10 satellite undergoing testing in a NASA laboratory prior to being launched in 1961. (credit: NASA)

Any of the largest (55-member) series of unmanned U.S. spacecraft, launched between 1958 and 1975. Explorer 1, the first satellite sent into orbit by the U.S., discovered the innermost Van Allen radiation belt. Other notable craft in this series include Explorer 38 (1968), which measured galactic radio sources and studied low radio frequencies in space, and Explorer 53 (SAS 3; 1975), which investigated X-ray and gamma-ray sources within and beyond the Milky Way Galaxy.

For more information on Explorer, visit Britannica.com.

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A dental instrument with a slender head that is honed to a fine point, used to conduct a tactile examination and appraisal of pits and fissures, carious lesions, root surfaces, and margins of restoration.

Explorers. (Daniel/Harfst, 2002)

• Space Exploration and Rocketry - Explorer: first series of NASA space probes

Dansk (Danish)
n. - opdagelsesrejsende

Nederlands (Dutch)
ontdekkingsreiziger, onderzoeker, deelnemer aan programma voor beroepskeuze (V.S.)

Français (French)
n. - explorateur

Deutsch (German)
n. - Forschungsreisender

Ελληνική (Greek)
n. - εξερευνητής

Italiano (Italian)
esploratore

Português (Portuguese)
n. - explorador (m), sonda (f)

Русский (Russian)
исследователь

Español (Spanish)
n. - explorador

Svenska (Swedish)
n. - utforskare, upptäcktsresande

中文（简体）(Chinese (Simplified))
探险家, 探测者

中文（繁體）(Chinese (Traditional))
n. - 探險家, 探測者

한국어 (Korean)
n. - 탐험가, 탐색기구, 탐침

日本語 (Japanese)
n. - 探検家, 調査する人

العربيه (Arabic)
‏(الاسم) مسبار, المستكشف‏

עברית (Hebrew)
n. - ‮חוקר ארצות‬

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