天文学家们发现了一种奇特的新型恒星，它只在一侧脉动

天文学家们发现了一种奇特的新型恒星，它只在一侧脉动

The Universe has yielded another surprise, and this time, it's practically under our very noses. Just 1,500 light-years away, astronomers have found a star that pulsates - but only on one side. Although such an object was predicted decades ago, this is the first time we've actually seen it.

宇宙带来了另一个惊喜，而这一次，它就在我们的眼皮底下。就在1500光年远的地方，天文学家们发现了一颗跳动的恒星，但它只在一边。尽管早在几十年前就有人预测到这样一个天体，但这是我们第一次真正看到它。

"We've known theoretically that stars like this should exist since the 1980s," said astronomer Don Kurtz of the University of Central Lancashire in the UK.

英国中央兰开夏大学的天文学家唐·库尔兹说:“从理论上讲，我们从20世纪80年代就知道这种恒星应该存在。”

The star is called HD74423, an A-type main-sequence star about 1.7 times the mass of the Sun, and younger, too (although it's hard to age it precisely).

这颗恒星被称为HD74423，是一颗A型主序恒星，质量约为太阳的1.7倍，而且也更年轻(尽管很难精确地确定年龄)。

Its strange pulsing behaviour was first spotted by citizen scientists poring over data from NASA's exoplanet-hunting space telescope TESS, looking for anomalies.

它奇怪的脉冲行为最初是由平民科学家发现的，他们仔细研究了NASA的外行星搜寻太空望远镜TESS的数据，寻找异常现象。

Unsure of what they were seeing, they took their findings to professional astronomers, ultimately looping in Kurtz and astronomer Gerald Handler of the Nicolaus Copernicus Astronomical Centre in Poland.

由于不确定自己看到了什么，他们把自己的发现交给了专业天文学家，最终在库尔茨和波兰哥白尼天文中心的天文学家杰拉德·汉德勒(Gerald Handler)那里得到了证实。

Pulsations within a star aren't unusual. Many stars - maybe even all stars - oscillate in rhythmic patterns, caused by waves bouncing around inside the star. These waves are thought to be created by convection and the star's magnetic field; like earthquakes can be used to probe Earth's guts, the waves can reveal what's going on in stellar interiors.

恒星内部的脉动并不罕见。许多恒星——甚至可能是所有的恒星——都在有节奏地振动，这是由恒星内部的波动引起的。这些波被认为是由对流和恒星磁场产生的;就像地震可以用来探测地球内部一样，这些波也可以揭示恒星内部的情况。

But in all other stars prior to HD74423, these oscillations could be detected globally; that is, over the entire surface of the star. So why is HD74423 such a weirdo?

但在HD74423之前的所有其他恒星中，这些振荡可以在全球范围内被探测到;也就是说，在恒星的整个表面。那么，为什么HD74423如此古怪呢?

Well, it has a friend. A really close friend. The pulsating star's binary companion is a red dwarf, and the two are locked in a super-tight orbit of just 1.6 days. At that proximity, the gravity of the red dwarf is distorting HD74423, pulling it into more of an egg or teardrop shape.

嗯，因为它有一个朋友，一个非常亲密的朋友。这颗脉动恒星的双星伴侣是一颗红矮星，这两颗星被锁定在一个超紧密的轨道上，周期只有1.6天。在这个距离上，红矮星的引力使HD74423变形，使它更像一个鸡蛋或泪滴形状。

But that's not the only thing weird about HD74423. As researchers started examining the object more closely, astronomer Simon Murphy of the University of Sydney in Australia was noticing some unusual chemical abundances.

但这并不是HD74423唯一奇怪的地方。当研究人员开始更仔细地研究这个物体时，澳大利亚悉尼大学的天文学家西蒙墨菲(Simon Murphy)发现了一些不寻常的化学物质丰度。

"What first caught my attention was the fact it was a chemically strange star," Murphy said. "Stars like this are usually fairly rich with metals - but this is metal poor, making it a rare type of hot star."

墨菲说:“首先引起我注意的是，这是一颗化学性质奇特的恒星。”“像这样的恒星通常含有丰富的金属，但这颗恒星缺乏金属，这使得它成为一种罕见的热恒星。”