|
}} Luna 15 was an unmanned space mission of the Soviet Luna programme. On 21 July 1969, while Apollo 11 astronauts finished the first human moonwalk, Luna 15, an unmanned Soviet spacecraft in lunar orbit at the time, began its descent to the lunar surface. Launched three days before the Apollo 11 mission, it was the second Soviet attempt to return lunar soil back to Earth with a goal to outstrip the US in sample return under Moon race. The Russian craft crashed into the Moon at 15:50 UT, hours before the scheduled American lift off from the Moon. ==Mission== Luna 15 was capable of studying circumlunar space, the lunar gravitational field, and the chemical composition of lunar rocks. It was also capable of providing lunar surface photography. Luna 15 was placed in an intermediate Earth orbit after launch and was then sent toward the Moon. After a mid-course correction the day after launch, Luna 15 entered lunar orbit at 10:00 UT on 17 July 1969. The spacecraft remained in lunar orbit for two days while controllers checked all on-board systems and performed two orbital manoeuvres. After completing 86 communications sessions and 52 orbits of the Moon at various inclinations and altitudes, it began its descent. Astronauts Armstrong and Aldrin had already set foot on the Moon when Luna 15 fired its main retrorocket engine to initiate descent to the surface at 15:47 UT on 21 July 1969. Transmissions ceased four minutes after de-orbit, at a calculated altitude of . The spacecraft had probably crashed into the side of a mountain. Impact coordinates were 17° north latitude and 60° east longitude, in Mare Crisium.〔 An audio recording of the minutes in which British technicians at the radio telescope facility in Jodrell Bank observed Luna 15's descent was first made available to the public on 3 July 2009.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Luna 15」の詳細全文を読む スポンサード リンク
|