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天文学家也许已经捕捉到附近系外行星”Proxima C”的第一张图像

Astronomers May Have Captured the First Ever Image of Nearby Exoplanet Proxima C

Little is more enticing than the prospect of seeing alien worlds around other stars—and perhaps one day even closely studying their atmosphere and mapping their surface. Such observations are exceedingly difficult, of course. Although more than 4,000 exoplanets are now known, the vast majority of them are too distant and dim for our best telescopes to discern against the glare of their host star. Exoplanets near our solar system provide easier imaging opportunities, however. And no worlds are nearer to us than those thought to orbit the cool, faint red dwarf Proxima Centauri—the closest star to our sun at 4.2 light-years away.

没有什么比看到其他恒星周围的外星世界更吸引人的了——也许有一天甚至可以仔细研究它们的大气层并绘制它们的表面;当然,这样的观察是极其困难的,尽管目前已知的系外行星有4000多颗,但绝大多数都是太过于遥远、太暗(亮度),用我们最好的望远镜都无法分辨它们的主恒星所发出的强光;然而,太阳系附近的系外行星提供了更容易的成像机会,没有哪个星球比那些被认为围绕着寒冷、暗淡的红矮星比邻星(Proxima centauri)运行的星球离我们更近了——比邻星是离我们太阳最近的恒星,它距离我们4.2光年。

In 2016 astronomers discovered the first known planet in this system: the roughly Earth-sized Proxima b. But because of its star-hugging 11-day orbit around Proxima Centauri, Proxima b is a poor candidate for imaging. Proxima c, by contrast, offers much better chances. Announced in 2019, based on somewhat circumstantial evidence, the planet remains unconfirmed. If real, it is estimated to be several times more massive than Earth—a so-called super Earth or mini Neptune—and to orbit Proxima Centauri at about 1.5 times the span between Earth and the sun. Its size and distance from its star make the world a tempting target for current and near-future exoplanet-imaging projects. Now, in a new preprint paper accepted for publication in the journal Astronomy & Astrophysics, some astronomers say they might—just might— have managed to see Proxima c for the first time.

2016年,天文学家发现了这个星系中已知的第一颗行星:近似地球大小的Proxima b。但由于它围绕着比邻星(Proxima Centauri)运转了11天,所以Proxima b不太适合成像;相比之下Proxima c则提供了更好的机会;根据一些间接证据表明,这颗行星于2019年被宣布存在了,但至今仍未得到证实;如果是真的,那么它的质量估计是地球的几倍——所谓的“超级地球”或“迷你海王星”——它围绕着比邻星(Proxima Centauri)公转的距离大约是地球和太阳距离的1.5倍,它的大小和离恒星的距离使它成为当前和不久的将来外行星成像项目的诱人目标;现在,在一篇即将发表在《天文学与天体物理学》杂志上的预印本上,有一些天文学家说他们可能,仅仅是可能第一次看到了Proxima C。

Read more at Scientific American