Rocket propellant has barely changed in the more than 50 years since the launch of the first artificial satellite Sputnik.

自第一颗人造卫星史泼尼克发射以来，火箭推进剂在超过50年的时间内变化不多。

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Sputnik - the first artificial satellite - is launched by the Soviet Union on October 4, 1957, as a global positioning system for precise weapon delivery and paves the way for GPS as we know it today.

1957年10月4日，苏联发射了首颗人造卫星“斯普特尼克”作为精准武器的全球定位系统，为我们今天所知的GPS铺平了道路。

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Do you know when the first artificial satellite of America was launched?

你知道美国的第一颗人造卫星是什么时候发射的吗？

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Twelve years before the historic Apollo 11 mission, the Soviets successfully launched the first artificial satellite called Sputnik into Earth's orbit.

VOA: standard.2009.07.16

Our scientists and technicians have succeeded in launching the first artificial satellite aboard a multi-stage rocket into orbit.

BBC: Satellite 'transmitting revolutionary hymns'

The successful launch of the first artificial satellite in the DPRK greatly encourages the Korean people in the efforts to build a powerful socialist state under the wise leadership of the great leader Kim Chong-il.

BBC: Satellite 'transmitting revolutionary hymns'

And after the Soviet launch of Sputnik, the first artificial satellite to orbit the Earth, the United States went about winning the Space Race by investing in science and technology, leading not only to small steps on the moon but also to tremendous economic benefits here on Earth.

WHITEHOUSE: President Obama Pushes Clean Energy