科学家认为，我们太阳系之外存在一些行星，那里的生命可能比地球上更丰富、更可持续。
Scientists believe there are planets outside our solar system where life is even more abundant and sustainable.
几年前，在柏林的一家实验室里，天体生物学家伊娃·维洛维奇（Iva Vilović）观察到，旱金莲在一种模拟“K型矮星”光线的灯光下发芽，她感到非常兴奋。K型矮星是一种橙色的恒星，比我们的黄色太阳更凉爽，燃烧得更缓慢。令她惊讶的是，这些旱金莲在模拟阳光下生长得更快、更高。
A few years ago, in a lab in Berlin, the astrobiologist Iva Vilović was thrilled when she observed garden cress sprouting under a light designed to mimic a “K-dwarf” star — an orange-hued star that’s cooler and slower burning than our yellow sun. To her surprise, the cress grew even faster and taller than it did under simulated sunlight.
她的研究结果表明，光合作用——为地球整个食物网提供能量的过程——可以在围绕这些橙色恒星运行的行星上发生。“在我看来，K型矮星的光是一种非常、非常有趣的光源，对于任何类型的地外生命搜索，都应该予以考虑，甚至应当优先考虑，”维洛维奇博士说，她目前在德国波茨坦的莱布尼茨天体物理研究所工作。
Her results suggested that photosynthesis, the process that supplies the energy for Earth’s entire food web, can happen on planets orbiting these orange stars. “K-dwarf light is a very, very interesting light source, and it should be considered, if not prioritized, for any type of search for extraterrestrial life, in my opinion,” said Dr. Vilović, now at the Leibniz Institute for Astrophysics in Potsdam, Germany.
特别是，外星生命可能在这些恒星的光芒下繁衍生息，栖息于比地球略大的行星上，这些行星被称为“超级地球”。像维洛维奇博士这样的科学家认为，围绕K型矮星运行的超级地球，实际上可能是银河系中最充满生机的地方——也许比地球更适合生命存在。
In particular, alien life may thrive in the light of these stars on planets that are slightly larger than Earth, known as super-Earths. Scientists like Dr. Vilović believe super-Earths that orbit K-dwarfs might, in fact, be the liveliest places in the galaxy — perhaps even more suitable for life than here.
科学家将这些行星称为“超宜居世界”，即能让碳基生命延续更长时间，并比地球上更加复杂和多样化的行星。
Scientists call these “superhabitable worlds,” planets that would allow carbon-based life to persist longer and become even more complex and diverse than on Earth.
科学家想象中的超宜居世界，直径比地球大20%到30%，质量是地球的两倍，并且位于与恒星的适当距离处，使得水可以在其表面流动。这颗更大的地球拥有更强的引力，能比地球更紧密地抓住周围的分子，从而拥有更厚的大气层和更温暖、更稳定的气候，滋养外星植物和动物（或其等价物）的生长。超级地球更大的铁核会在其周围形成更强的磁场，更好地阻挡宇宙辐射。
A superhabitable world — as scientists imagine it — is about 20 to 30 percent wider and twice as massive as Earth, and is placed at the right distance from its star for water to flow on its surface. The stronger gravity of this bigger Earth would hold on tighter to ambient molecules than Earth does, giving the planet a thicker atmosphere and a warmer and more stable climate, fueling the growth of extraterrestrial plants and animals (or their equivalents). The super-Earth’s bigger iron core would erect a stronger magnetic field around it, better blocking cosmic radiation.
至于这颗超级宜居行星的表面，可以想象成天堂。放大的星球会比地球更圆、更光滑，因为更强的重力会侵蚀大陆架并填平海沟。水会均匀地洒满其表面，形成浅湖和海洋。
As for the superhabitable planet’s surface, picture paradise. An enlarged orb would be rounder and smoother than Earth, as its stronger gravity erodes continental shelves and fills in trenches. Water would spill evenly over its surface as shallow lakes and seas.