在銀河系中心發(fā)現(xiàn)的奇怪物體與銀河系中的其他物體完全不同
There's something really weird in the centre of the Milky Way.
銀河系的中心有個很奇怪的東西。
The vicinity of a supermassive black hole is a pretty weird place to start with, but astronomers have found six objects orbiting Sagittarius A* that are unlike anything in the galaxy. They are so peculiar that they have been assigned a brand-new class - what astronomers are calling G objects.
一開始,超大質(zhì)量黑洞附近是一個相當怪異的地方,但天文學家已經(jīng)發(fā)現(xiàn)了六個環(huán)繞人馬座a *運行的天體,它們與銀河系中的任何天體都不同。它們是如此特別,以至于被賦予了一個全新的類別——天文學家們稱之為G類天體。
The original two objects - named G1 and G2 - first caught the eye of astronomers nearly two decades ago, with their orbits and odd natures gradually pieced together over subsequent years. They seemed to be giant gas clouds 100 astronomical units across, stretching out longer when they got close to the black hole, with gas and dust emission spectra.
最初的兩個天體——G1和G2——在近20年前首次引起天文學家的注意,它們的軌道和古怪的性質(zhì)在隨后的幾年里逐漸拼湊在一起。它們似乎是巨大的氣體云,直徑為100個天文單位,當它們靠近黑洞時,隨著氣體和塵埃發(fā)射光譜的出現(xiàn),它們被拉長了。
But G1 and G2 weren't behaving like gas clouds.
但G1和G2的表現(xiàn)并不像氣體云。
These objects look like gas but behave like stars, said physicist and astronomer Andrea Ghez of the University of California, Los Angeles.
加州大學洛杉磯分校的物理學家和天文學家Andrea Ghez說:“這些物體看起來像氣體,但實際上卻像恒星。”
Ghez and her colleagues have been studying the galactic centre for over 20 years. Now, based on that data, a team of astronomers led by UCLA astronomer Anna Ciurlo have identified four more of these objects: G3, G4, G5 and G6.
Ghez和她的同事已經(jīng)研究銀河系中心超過20年了?,F(xiàn)在,根據(jù)這些數(shù)據(jù),一個由加州大學洛杉磯分校的天文學家Anna Ciurlo領導的天文學家小組已經(jīng)確定了另外四個這樣的天體:G3、G4、G5和G6。
And they're on wildly different orbits from G1 and G2 (pictured above); all together, the G objects have orbital periods that range from 170 years to 1,600 years.
它們的運行軌道與G1和G2截然不同(見上圖);總的來說,G星的軌道周期從170年到1600年不等。
It's unclear exactly what they are, but G2's intact emergence from periapsis in 2014 - that is, the closest point in its orbit to the black hole - was, Ghez believes, a big clue.
目前還不清楚它們到底是什么,但是G2在2014年完整地從periapsis(即其軌道上距離黑洞最近的點)的出現(xiàn),Ghez相信,是一個重要的線索。
The research has been published in Nature.
這項研究發(fā)表在《自然》雜志上。