我们发现了三颗岩石系外行星，它们围绕着一颗12光年外的恒星运行

Three new exoplanets have been found orbiting a nearby star, and one of them is ranked pretty highly for potential habitability.

三颗新的系外行星围绕着附近的一颗恒星运行，其中一颗行星的潜在宜居性非常高。

All three are rocky, and within the vicinity of Earth-sized - and the outermost is orbiting the star in the habitable zone, where temperatures are compatible with the possibility of liquid water on the surface.

这三颗行星都是岩石构成的，而且都在地球大小的范围内——最外层是围绕恒星运行的宜居带，那里的温度与表面液态水存在的可能性相匹配。

The star is Gliese 1061, at a distance of 3.67 parsecs - around 12 light-years away - making it the 20th closest star to the Solar System. And its three planets are Gliese 1016 b, Gliese 1016 c and Gliese 1016 d.

颗恒星是Gliese 1061，距离为3.67秒秒，大约12光年，是离太阳系最近的第20颗恒星。它的三颗行星是Gliese 1016b, Gliese 1016c和Gliese 1016d。

The research team also found evidence that could indicate a fourth planet, but ultimately ruled it out as stellar activity. The findings are reported on preprint server arXiv, and have been submitted to the Monthly Notices of the Royal Astronomical Society.

研究小组还发现了可能存在第四颗行星的证据，但最终排除了它是恒星活动的可能性。这些发现已在预印本服务器arXiv上发表，并已提交给英国皇家天文学会(Royal Astronomical Society)的月报。

Gliese 1061 is a red dwarf. These stars are cool and faint, which means their habitable zone is a lot closer to the star than a hotter, brighter star - like the Sun, for instance. And planets orbiting their stars closely are easier to find than stars much farther out.

格利泽1061是一颗红矮星。这些恒星又冷又暗，这意味着它们的宜居带比更热、更亮的恒星(比如太阳)离恒星更近。而且，与距离较远的恒星相比，距离较近的行星更容易被发现。

This makes them a great target for habitable exoplanet searches, but that doesn't mean they're necessarily hospitable.

这使得它们成为寻找宜居系外行星的绝佳目标，但这并不意味着它们一定适合居住。

Red dwarfs are often restless and wild, lashing the space around them with stellar flares.

红矮星通常是不安分和狂野的，用恒星耀斑猛烈地冲击着它们周围的空间。

Such is the case with Proxima b, the rocky exoplanet found orbiting in the habitable zone of our nearest stellar neighbour, Proxima Centauri.

比邻A B就是这样一个例子，它是一颗多岩石的外行星，在我们最近的恒星邻居比邻A半人马座的可居住区域中被发现。

Gliese 1061 is a lot like Proxima Centauri, but there is one key difference: it's a heck of a lot quieter. Which means - you guessed it - potentially higher chances of habitability.

Gliese 1061很像比邻星，但有一个关键的区别:它要安静得多。这意味着——你猜对了——潜在的更适合居住的机会。

All three planets were detected using the radial velocity, or "wobble", method.

所有三颗行星都是用径向速度(或称为“摆动”)方法探测到的。

While many exoplanets are identified by looking at dips in light as the planets pass between us and their star (the transit method), in this instance, the stars' orbits are angled so that they never pass between us and the star. That means we have to detect them using gravity.

虽然许多系外行星是通过观察行星在我们和它们的恒星之间运行时的光线变化来确定的(凌日法)，但在这种情况下，恒星的轨道是有角度的，因此它们永远不会在我们和恒星之间运行。这意味着我们必须利用重力来探测它们。

You see, although it seems like a star might be more or less fixed in position, the planet and the star actually orbit a mutual centre of gravity. This is usually inside the star, since it is so much more massive than its planets, but the tug of the planet is enough to pull the star just ever-so-slightly off-centre as it moves around.

你看，虽然看起来恒星或多或少固定在某个位置上，但行星和恒星实际上绕着一个相互的重心运行。这通常是在恒星内部，因为它比行星要大得多，但是行星的引力足以使恒星在移动时稍微偏离中心。

If you have precise enough detection methods - which we do - this wobble can be used not just to infer the presence of a planet (or several planets), but to calculate their mass, based on how much the star is wobbling.

如果你有足够精确的检测方法——我们有——这种摆动不仅可以用来推断行星(或几个行星)的存在，而且可以根据恒星摆动的程度来计算它们的质量。

This returned some pretty interesting masses for Gliese 1061's planets. Gliese 1016 b - the innermost planet - is 1.38 times the mass of Earth. The middle planet, Gliese 1016 c, is 1.75 times the mass of Earth. And the outermost planet, Gliese 1016 d, is 1.68 times the mass of Earth.

这为Gliese1061的行星返回了一些相当有趣的质量。最里面的行星gliese 1016 b是地球质量的1.38倍。中间的行星gliese 1016 c是地球质量的1.75倍。最外层的行星gliese 1016 d是地球质量的1.68倍。

This is also how we infer the planets are rocky, since those masses are rarely seen in gaseous exoplanets.

这也是我们推断行星是多岩石的原因，因为这些质量在气态系外行星中很少见到。

All three planets orbit the star much closer than any of the Solar System's planets. Gliese 1016 b whips round every 3.1 days; Gliese 1016 c every 6.7 days; and Gliese 1016 d every 13 days. The star is so cool that these orbits place Gliese 1016 d in the habitable zone, and Gliese 1016 c is right on the innermost cusp of the habitable zone.

所有三颗行星围绕恒星运行的轨道都比太阳系的任何一颗行星都要近得多。Gliese 1016 b每3.1天旋转一次;Gliese 1016 c每6.7天;格利泽1016 d每13天。这颗恒星是如此的冷，以至于这些轨道将Gliese 1016d置于宜居带，而Gliese 1016c正好位于宜居带的最深层。

Of course, this doesn't mean life is waiting for us to find it just 12 light-years away.

当然，这并不意味着生命正等着我们在12光年之外找到它。

As the researchers note, the star may be relatively quiet now, but it probably was quite active in its recent past. If it has been bathing its planets in stellar radiation, any life that was there is unlikely to have survived.

正如研究人员所指出的，这颗恒星现在可能相对比较安静，但在它最近的过去可能相当活跃。如果它一直将行星沐浴在恒星辐射中，那里的任何生命都不太可能存活下来。

But it does add to the tally of rocky planets in nearby space. According to the Exoplanet Archive, somewhere in the vicinity of 70 exoplanets have been located within 10 parsecs (32.6 light-years) of the Solar System, many of them small and possibly rocky.

但它确实增加了附近太空中岩石行星的数量。根据系外行星档案，大约有70颗系外行星位于距太阳系10秒(32.6光年)的范围内，其中许多都很小，可能是岩石构成的。

And just a couple of months ago, astronomers revealed the presence of two Earth-like planets orbiting Teegarden's star 12.5 light-years away. With at least half of all red dwarf stars thought to have rocky planets, our local neighbourhood suddenly seems quite bustling, really.

就在几个月前，天文学家们发现了两颗类地行星的存在，它们围绕着蒂加登12.5光年远的恒星运行。至少有一半的红矮星被认为有岩石行星，我们的邻居突然变得非常热闹，真的。

The research has been submitted to the Monthly Notices of the Royal Astronomical Society, and is available on arXiv.

这项研究已提交给英国皇家天文学会的月报，可在arXiv上找到。