Five very old galaxies are now known to astrophysicists, thanks to Albert Einstein. A century ago, Einstein predicted an effect called cosmic gravitational lensing. Picture a massive galaxy out in space. From our [--1--], a second galaxy happens to be behind the first galaxy. That second galaxy should be hidden to us. Except that the nearer galaxy [--2--] the light of the far galaxy coming our way. That light can sometimes become so [--3--] that it actually appears to ring the nearer galaxy. It’s called an Einstein ring, because he predicted that, too.
In the new study, researchers used the Herschel Space Observatory. The brightest spots on their sky map all turned out to be gravitationally [--4--] galaxies. The study is in the journal Science.
The observatory is really detecting infrared info, or heat, rather than visible light from the newly discovered galaxies. That radiation [--5--] when the universe was only two to four billion years old, less than a third of its current age.
Researchers expect to find hundreds of new, old galaxies this way, along with new info about the early universe.
【視聽版科學(xué)小組榮譽出品】
vantage point
bends
distorted
magnified
started coming our way
透鏡效應(yīng):揭開古老星系面紗
多虧愛因斯坦,5個古老的星系在天體物理學(xué)家們中耳熟能詳.一個世紀(jì)以前,愛因斯坦預(yù)言了一種宇宙引力透鏡效應(yīng).想象宇宙中有一個巨大的星系,從我們的有利觀測點看,第二個星系恰巧就在第一個星系后面.而這第二個星系應(yīng)該是在跟我們”躲貓貓”.只是近星系彎曲了從遠星系過來的光線.這個光線有時候會變得十分扭曲,使其看起來就像是近星系的一個環(huán).這就是愛因斯坦環(huán),因為這也是他預(yù)言的.
在一項新研究中,研究人員使用赫歇爾空間天文臺.他們的天圖上所有最亮的點都被證明是引力放大星系.這項研究收藏在<科學(xué)>期刊中.
天文臺時刻都在探測紅外信號和熱信號,而不僅僅探測從新發(fā)現(xiàn)的星系發(fā)出的可見光.這些星系發(fā)出的光到達我們星球時,它們才二十到四十億歲,不足它們現(xiàn)有現(xiàn)有年齡的三分之一.研究人員期望用這種方式從上百個新舊星系中發(fā)現(xiàn)一些關(guān)于早期宇宙的新信息.