<tt id="6hsgl"><pre id="6hsgl"><pre id="6hsgl"></pre></pre></tt>
          <nav id="6hsgl"><th id="6hsgl"></th></nav>
          国产免费网站看v片元遮挡,一亚洲一区二区中文字幕,波多野结衣一区二区免费视频,天天色综网,久久综合给合久久狠狠狠,男人的天堂av一二三区,午夜福利看片在线观看,亚洲中文字幕在线无码一区二区

          1st planet orbiting 2 stars discovered

          Updated: 2011-09-16 14:13

          (Xinhua)

            Comments() Print Mail Large Medium  Small 分享按鈕 0

          1st planet orbiting 2 stars discovered

          NASA handout image shows an artist's concept of the circumbinary planet Kepler-16b - the first planet known to definitively orbit two stars. [Photo/Agencies]

          WASHINGTON - A team of researchers has discovered a planet that orbits around a pair of stars, the US space agency NASA announced Thursday.

          This is the first instance of astronomers finding direct evidence of a so-called circumbinary planet. A few other planets have been suspected of orbiting around both members of a dual-star system, but the transits of the circumbinary planet have never been detected previously.

          The team, led by Laurance Doyle of the SETI Institute in California, used photometric data from the NASA Kepler space telescope, which monitors the brightness of 155,000 stars.

          They found the binary star system by detecting a system where the stars eclipsed each other from the perspective of the Kepler spacecraft. These stars have two eclipses: A primary eclipse when the larger star is partially blocked by the smaller star and a secondary eclipse where the smaller star is fully blocked by the larger star.

          But the researchers also noticed other times when the brightness of the two stars dropped, even when they were not in an eclipse position. This pattern suggested that there was likely a third object involved. The fact that these so-called tertiary and quaternary eclipses recurred after varying intervals of time, and were of different depths, indicated that the stars were in different positions in their orbit at each instance. This result showed that the tertiary and quaternary eclipses were being caused by something circling both stars, and not an object circling one or the other star.

          Measurements of the variations in the timing of all four types of eclipses, resulting from the mutual gravitational interactions of the two stars and the third body, demonstrated that the third object was, indeed, a planet. Their work indicates that the planet is less massive than Jupiter, possibly comparable in mass to Saturn, and that the larger of the two binary stars is smaller than our Sun.

          Their findings will be published Friday in Science.

          "This discovery confirms a new class of planetary systems that could harbor life," Kepler principal investigator William Borucki said in a statement. "Given that most stars in our galaxy are part of a binary system, this means the opportunities for life are much broader than if planets form only around single stars. This milestone discovery confirms a theory that scientists have had for decades but could not prove until now."

             Previous Page 1 2 Next Page  

          主站蜘蛛池模板: 亚洲国产精品日韩在线| 亚洲一区成人在线视频| 亚洲色成人一区二区三区人人澡人人妻人人爽人人蜜桃麻豆 | 欧美最大胆的西西人体44| 亚洲日产无码av| 久久综合色最新久久综合色| 夜夜爱夜鲁夜鲁很鲁| 亚洲综合色婷婷中文字幕| 狠狠色狠狠综合久久| 日韩有码av中文字幕| 成熟少妇XXXXX高清视频| 99久久亚洲综合精品成人| 国产亚洲av天天在线观看| 国产精品论一区二区三区| 九九热在线视频精品免费| 亚洲qingse中文字幕久久| 免费在线成人网| 色老头在线一区二区三区| 99久久婷婷国产综合精品青草漫画 | 国产成人精品一区二区秒拍1o | 精品亚洲精品日韩精品| 国产精品青青在线观看爽香蕉| 乱公和我做爽死我视频| 久久一亚色院精品全部免费| 又大又粗欧美成人网站| 日本中文字幕一区二区三| 尹人香蕉久久99天天拍| 久久精品视频一二三四区| 91香蕉国产亚洲一二三区| 久久久精品国产亚洲AV蜜| 九色国产精品一区二区久久| 亚洲国产精品嫩草影院久久 | 人人妻人人澡人人爽人人精品电影| 日本中文字幕一区二区三| 伊人av超碰伊人久久久| 国产玩具酱一区二区三区| 69精品丰满人妻无码视频a片| 中文字幕va一区二区三区| 视频一区视频二区在线视频| 天堂亚洲免费视频| 国产成人亚洲综合A∨在线播放|