早在19世纪便有天文学家声称发现了系外行星(太阳系之外的行星),不过人们普遍认为直到1992年才首次真正证实了系外行星的存在(环绕着脉冲星PSR B1257+12的天体)。自那之后,其他系外行星陆陆续续被人们揭开神秘面纱。截至2016年2月22日,总共有2085颗已确认的系外行星,而天文学家曾估计银河系可能包含多达4000亿颗系外行星。随着系外行星的发现,一个相当令人感兴 As early as the 19th century, astronomers claimed to have discovered extrasolar planets (planets outside the solar system), although it was generally accepted that the existence of extrasolar planets was not confirmed for the first time in 1992 (orbiting the pulsar PSR B1257 + 12 ). Since then, other extrasolar planets have been unveiled mysteriously. As of February 22, 2016, there are a total of 2,085 confirmed extrasolar planets, and astronomers have estimated that the Milky Way may contain up to 400 billion extrasolar planets. With the discovery of extrasolar planets, one is quite impressive