NASA星期五發射太陽能木星探測器

NASA's solar-powered Juno spacecraft is ready to blast off Friday on a landmark mission to Jupiter aimed gaining new insight into the origin and evolution of the solar system’s largest planet.

The unmanned U.S. space agency probe will launch aboard an Atlas V551 rocket ((Friday 1534 Universal Time/11:34 am Eastern time)) from Cape Canaveral in ((the southeastern U.S. state of)) Florida. Juno is scheduled to reach Jupiter in 2016.

But just minutes after it separates from the launch vehicle, NASA says Juno will begin opening its large solar arrays and begin powering up the nearly 19,000 solar cells that will be the spacecraft’s energy source for its more than six-year mission - a journey of nearly 3.5 billion kilometers. Previous NASA missions to the outer solar system relied on nuclear energy.

NASA says the probe will orbit around Jupiter’s poles and get closer to the planet than any spacecraft before it. At its nearest approach, Juno will fly a 5,000 kilometers above the gas giant, nearly skimming its dense, swirling cloud tops. Jupiter is the fifth planet from the Sun, orbiting between Mars and the ringed planet, Saturn.

In addition to learning more about Jupiter’s atmosphere, core, strong gravity and powerful magnetic field, scientists hope the Juno mission will unlock the mystery of the so-called Great Red Spot - an enormous cyclonic storm three times the size of the Earth that has raged on Jupiter for more than 300 years.美國航空航天局的太陽能航天器“朱諾號”已經爲星期五前往木星的極具里程碑意義的發射升空作好準備。“朱諾號”此行的使命是進一步瞭解木星這個太陽系最大行星的起源和進化情況。

“朱諾號”無人探測器將從美國東南部佛羅里達州的卡納維拉爾角搭載擎天神V551型火箭升空。預計，“朱諾號”將在2016年飛抵木星。

美國航空航天局說，在離開發射器幾分鐘後，“朱諾號”探測器將打開自己的巨型太陽能板。屆時，太陽能板上的19000個太陽能電池將會充電，併成爲朱諾六年多使命的能源來源。這次旅行的總行程將達到將近35億公里。美國航空航天局以往的前往太陽系外部空間使命都是依靠核能。

美國航空航天局說，這個探測器將環繞木星飛行，並比以往任何航空器都更接近木星。在距離木星最近時，“朱諾號”將在這個巨大行星上空5千公里的高度飛行，非常接近木星上空浮動的厚雲。木星是距離太陽第五遠的行星，在火星和帶有光環的土星之間運行。

除了瞭解有關木星大氣層、核、強大的引力以及磁場之外，科學家們還希望“朱諾號”的使命能夠揭開所謂“大紅斑”之謎。“大紅斑”是一個巨大的旋風暴，體積是地球的三倍，在木星上已經存在300多年。