... Explorers 1/3 . ... Orbit . ... Launch of Explorer 1 . ... The USSR was first, sending off its first "Sputnik" ("satellite") on October 4, followed by Sputnik II on November 3. ... The spacecraft, named Explorer 1, was launched 31 January 1958 and was designed and built by a group of scientists from the University of Iowa, led by James Van Allen . ... the launch of Explorer 1;Click . ... Explorer 2 failed to orbit, but Explorer 3, launched March 26, was successful, and it did carry a tape recorder. ...

Lanzamiento del Explorer 1 . Pulse aqu para ver una versi n . ... Por lo que se autoriz a otra misi n de veh culos espaciales, iniciada no oficialmente unos a os antes por Wernher Von Braun. ... lanzamiento del Explorer 1; . ... A diferencia de las rbitas de los Sputniks, la del Explorer 1 era muy el ptica y ascendi hasta una altitud de unos 2500 km. ... Un sitio web con una imagen del cohete Explorer-1 y enlaces. ... Para saber m s sobre la historia de los Explorer 1 y Sputnik, pulse aqu . ...

Magellan to Venus . ... The spacecraft carried a sophisticated imaging radar, which was used to make the most highly detailed map of Venus ever captured during its four years in orbit around Venus from 1990 to 1994. After concluding its radar mapping, Magellan also made global maps of Venus's gravity field. ... The Magellan mission was divided up into "cycles" with each cycle lasting 243 days (the time necessary for Venus to rotate once under the Magellan orbit). ... Magellan Orbiting Venus . ...

Cosmic Research, Vol. 42, No. 5, 2004, pp. 435­488. Translated from Kosmicheskie Issledovaniya, Vol. 42, No. 5, 2004, pp. 453­508. Original Russian Text Copyright © 2004 by Veselovsky, Panasyuk, Avdyushin, Bazilevskaya, Belov, Bogachev, Bogod, Bogomolov, Bothmer, Boyarchuk, Vashenyuk, Vlasov, Gnezdilov, Gorgutsa, Grechnev, Denisov, Dmitriev, Dryer, Yermolaev, Eroshenko, Zherebtsov, Zhitnik, Zhukov, Zastenker, Zelenyi, Zeldovich, Ivanov-Kholodnyi, Ignat'ev, Ishkov, Kolomiytsev, Krasheninnikov, Kudela,