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新聞來源
Siliconrepublic INNOVATION

記者
Colm Gorey

標題
Star seen ‘dancing’ around supermassive black hole proves Einstein was right
繞著黑洞跳舞的恆星證明愛因斯坦是對的

完整連結
https://is.gd/zTmvyw



    A star was seen orbiting a supermassive black hole in the way that
     Einstein’s general theory of relativity had predicted.

觀察到有一顆恆星以愛因斯坦廣義相對論所預測的軌跡繞著超級黑洞運行。


    The European Southern Observatory’s (ESO) Very Large Telescope
    has revealed the first sighting of a star orbiting a supermassive
    black hole in a rather unique way at the centre of the Milky Way.
    This breakthrough, almost 30 years in the making, was predicted by
     Albert Einstein’s general theory of relativity.

ESO 超大望遠鏡揭露：在銀河系中心，首次觀察到一顆以相當獨特的軌跡繞著
超級黑洞的恆星。愛因斯坦的廣義相對論中預言了這個突破（將近30年的發展）。


    Writing in Astronomy and Astrophysics, a team of researchers
    described the star’s orbit as having a rosette shape, unlike the
    ellipse shape as predicted by Isaac Newton’s theory of gravity.

 研究團隊在<<天文學與天文物理學>> 寫道：這個恆星的軌跡不像是牛頓引力理論
預測的「橢圓形」;這個恆星軌跡是玫瑰(or 蓮葉)形狀。


    Located 26,000 light years from the sun, Sagittarius A* and its
    surrounding dense cluster of stars is described by ESO as being a
    “unique laboratory for testing physics” in an otherwise
    unexplored and extreme regime of gravity.

距離太陽約 26000 光年的人馬座A* 和周圍的星團在未知且極端的重力下，
被 ESO 形容是「檢驗物理學獨一無二的實驗室」


    One of these stars, named S2, sweeps towards the supermassive
    black hole and gets within 20bn km of it on the star’s closest
    approach. Equivalent to 120 times the distance from Earth to the
    sun, this makes it one of the closest stars ever found in orbit
    around the black hole.

至今發現最靠近黑洞的其中一顆恆星 S2 掃向超級黑洞，S2 軌跡掃過最近的距離
在 200 億公里以內（約為地球到太陽的距離的 120倍）

========

    4m times the mass of our sun
 比太陽重400萬倍


    When S2 is at its closest approach to the black hole, it is
    hurtling through space at 3pc of the speed of light, completing an
     orbit once every 16 years. Using these latest figures, the
    astronomers can predict that Sagittarius A* must have a mass 4m
    times that of our sun.

當 S2 離黑洞最近時，會以光速衝出 3 單位(秒差距) 至太空，每 16 年完成繞行一次。
若用這些最新的資料，天文學家預測射手座的A* 至少比太陽重400萬倍。


    The orbit of S2 makes it a significant outlier, as typically stars
     and planets will move closer to and further away from the object
    they are rotating around. However, S2’s orbit precesses, meaning
    that the location of its closest point to the supermassive black
    hole, change with each turn – resulting in the rosette shape.

S2 的玫瑰軌跡是一個顯著的異常值，一般來說，恆星跟行星的運行是靠近與遠離;
但是 S2 的軌跡顯示了當 S2 在最靠近超級黑洞時，每次的旋轉都會改變，最終
形成玫瑰型。


    This effect, known as Schwarzschild precession, had never before
    been measured for a star around a supermassive black hole.

這種效應(Schwarzschild precession)之前從來沒有對超級黑洞附近的恆星觀察過。


    Over 27 years of observations of the S2 star, ESO’s instruments
    made more than 330 measurements. Now, with the organisation’s
    upcoming Extremely Large Telescope, the team believes it will be
    possible to see even fainter stars orbiting the supermassive black
     hole.

使用超過 330 方法、經過了 27 年的觀察。之後會有更厲害的望遠鏡問世，研究團隊
相信我們可以看見更暗的恆星也繞著超大質量黑洞運行。


    “If we are lucky, we might capture stars close enough that they
    actually feel the rotation, the spin, of the black hole,” said
    Andreas Eckart from Cologne University, one of the lead scientists
     of the project. “That would be again a completely different
    level of testing relativity.”

 Cologne 大學的 Andreas Eckart 說：幸運的話，我們能很精確地捕捉到星體在黑洞旁
其實是自轉或自旋的。而到時候是對相對論完全不同層級的驗證。



https://imgur.com/xes3WP1

    This simulation shows the orbits of stars very close to the
    supermassive black hole at the heart of the Milky Way. Image:
    ESO/L Calçada/spaceengine.org
此為模擬圖，說明在銀河系中的星體，其軌跡非常靠近超級黑洞


https://imgur.com/HnNCglA


    Artist’s impression of S2’s orbit around the supermassive black
    hole. Image: ESO/L Calçada
專家對繞著超級黑洞的 S2 軌跡的模擬



6.備註:
    非本科，努力翻翻（就是不精準的意思啦 >w<）
來釣一下天文學大大，玫瑰型的軌跡 484 暨黑洞照的最新進展(?)

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