会懂英语的童鞋翻译翻译
From:WWW.NASA.GOV
The 2012 Transit of Venus
2012年金星凌日
On June 5th, 2012, Venus will pass across the face of the sun, producing a silhouette that no one alive today will likely see again.
Transits of Venus are very rare, coming in pairs separated by more than a hundred years. This June's transit, the bookend of a 2004-2012 pair, won't be repeated until the year 2117. Fortunately, the event is widely visible. Observers on seven continents, even a sliver of Antarctica, will be in position to see it.
The nearly 7-hour transit begins at 3:09 pm Pacific Daylight Time (22:09 UT) on June 5th. The timing favors observers in the mid-Pacific where the sun is high overhead during the crossing. In the USA, the transit will be at its best around sunset. That's good, too. Creative photographers will have a field day imaging the swollen red sun "punctured" by the circular disk of Venus.
Observing tip: Do not stare at the sun. Venus covers too little of the solar disk to block the blinding glare. Instead, use some type of projection technique or a solar filter. A #14 welder's glass is a good choice. Many astronomy clubs will have solar telescopes set up to observe the event; contact your local club for details.
Transits of Venus first gained worldwide attention in the 18th century. In those days, the size of the solar system was one of the biggest mysteries of science. The relative spacing of planets was known, but not their absolute distances. How many miles would you have to travel to reach another world? The answer was as mysterious then as the nature of dark energy is now.
Venus was the key, according to astronomer Edmund Halley. He realized that by observing transits from widely-spaced locations on Earth it should be possible to triangulate the distance to Venus using the principles of parallax.
The idea galvanized scientists who set off on expeditions around the world to view a pair of transits in the 1760s. The great explorer James Cook himself was dispatched to observe one from Tahiti, a place as alien to 18th-century Europeans as the Moon or Mars might seem to us now. Some historians have called the international effort the "the Apollo program of the 18th century."
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A double transit: the International Space Station and Venus on June 8, 2004. Photo courtesy of Tomas Maruska. In retrospect, the experiment falls into the category of things that sound better than they actually are. Bad weather, primitive optics, and the natural "fuzziness" of Venus’s atmosphere and other factors prevented those early observers from gathering the data they needed. Proper timing of a transit would have to wait for the invention of photography in the century after Cook’s voyage. In the late 1800s, astronomers armed with cameras finally measured the size of the Solar System as Edmund Halley had suggested.
This year’s transit is the second of an 8-year pair. Anticipation was high in June 2004 as Venus approached the sun. No one alive at the time had seen a Transit of Venus with their own eyes, and the hand-drawn sketches and grainy photos of previous centuries scarcely prepared them for what was about to happen. Modern solar telescopes captured unprecedented view of Venus’s atmosphere backlit by solar fire. They saw Venus transiting the sun’s ghostly corona, and gliding past magnetic filaments big enough to swallow the planet whole.
2012 should be even better as cameras and solar telescopes have improved. Moreover, NASA’s Solar Dynamics Observatory is going to be watching too. SDO will produce Hubble-quality images of this rare event.
谷歌给的翻译:
2012年6月5日,金星将通过跨面对太阳,生产,没有人今天还活着,可能会再次看到一个人影。
金星的过渡是非常罕见的,在相隔超过一百年的对未来。 今年6月的过境,在2004-2012年对一个书夹,不会被重复直到在2117年。 幸运的是,该事件是随处可见。 七大洲,甚至南极洲的条子,观察员将在位置看到它。
近7个小时的过境6月5日开始在3:09 PM太平洋夏令时(UT斯达康22时09分)。 时机主张在中太平洋,太阳是高开销在路口的观察员。 在美国,过境将在其周围日落最好的。 那太好了,太。 创意的摄影师将有一个重要的日子成像肿的红太阳“刺破”金星圆盘。
观测提示:不要盯着太阳金星占地面积太少阻挡眩目强光的太阳盘面。 相反,使用某种类型的投影技术或太阳能过滤。 #14焊工的玻璃是一个很好的选择。 许多天文俱乐部将成立太阳望远镜观察的事件;详情请洽询您当地的俱乐部。
金星第一次过境,在18世纪获得了全世界的关注。 在那些日子里,太阳系的规模最大的科学奥秘之一。 被称为行星的相对间距,但不是绝对的距离。 你有多少公里才能到达另一个世界吗? 答案是那样神秘暗能量的性质是现在。
金星是关键,根据天文学家埃德蒙·哈雷。 他意识到,从地球上观测广泛行距位置的过渡,它应该是可能的三角测量距离金星利用视差的原则。
的想法镀锌设置在世界各地的探险队,以查看在18世纪60年代对过境的科学家。 伟大的探险家詹姆斯·库克本人被派往观察从塔希提岛,外国人到月球或火星可能在我们看来,现在18世纪的欧洲人的地方。 一些历史学家称为“18世纪的阿波罗计划的国际努力。”
双过境:国际空间站,并于2004年6月8日,金星。 照片托马斯Maruska提供。回想起来,实验分为类的事情,声音比他们实际上是。 恶劣的天气,原始的光学和自然的金星大气层和其他因素的“模糊性”,阻止那些早期的观察员,收集他们所需要的数据。 过境的适当时机将不得不等待在新的世纪摄影术发明后,库克的远航。 在19世纪末期,用相机武装的天文学家终于测量太阳系的大小埃德蒙·哈雷曾建议。
今年的运输是一个8年对第二个。 预期于2004年6月,金星接近太阳。 没有人活着的时候曾见过金星凌日,用自己的眼睛和手绘草图和过去几百年的颗粒感的照片几乎没有准备,他们是即将发生。 现代太阳望远镜拍摄的金星大气层的太阳火背光前所未有的看法。 他们看到金星过境太阳的幽灵般的日冕,滑翔过去大到足以吞下地球整个磁场细丝。
2012年应该是更好的相机和太阳望远镜改善。 此外,美国宇航局的太阳动力学天文台将要看着太。 SDO会产生这种罕见的事件哈勃图像质量。
好像是能看到的地图:
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