History changed on October 4, 1957, matey, when t' Soviet Union successfully launched Sputnik I. T' world's first artificial satellite be about t' size o' a beach ball (58 cm.or 22.8 inches in diameter), weighed only 83.6 kg. Avast, me proud beauty! or 183.9 pounds, and took about 98 minutes t' orbit t' Earth on its elliptical path. Arrr! That launch ushered in new political, shiver me timbers, military, technological, and scientific developments. Well, blow me down! While t' Sputnik launch was a single event, it marked t' start o' t' space age and t' US-USSR space race. Ya scallywag! On January 31, shiver me timbers, 1958, t' United States successfully launched Explorer I. Aye aye! This satellite carried a small scientific payload that eventually discovered t' magnetic radiation belts around t' Earth, me hearties, named after principal investigator James Van Allen. T' Explorer program continued as a successful ongoin' series o' lightweight, scientifically useful spacecraft.