A candidate planet that might be remarkably similar to Earth, HD 137010 b, has one potentially big difference: It could be colder than perpetually frozen Mars.
HD 137010 b 是一颗可能与地球非常相似的候选行星，但它有一个潜在的巨大差异：它可能比永久冰冻的火星还要冷。
Scientists continue to mine data gathered by NASA’s Kepler Space Telescope , retired in 2018, and continue to turn up surprises. A new paper reveals the latest: a possible rocky planet slightly larger than Earth, orbiting a Sun-like star about 146 light-years away.
科学家们继续挖掘 NASA 于 2018 年退役的开普勒太空望远镜收集的数据，并不断发现惊喜。一篇新论文揭示了最新的情况：一颗可能比地球稍大的岩石行星，围绕着一颗距离我们约 146 光年的类太阳恒星运行。
The orbital period of the planet — listed as a “candidate” pending further confirmation — is likely to be similar to Earth’s, around one year. Planet HD 137010 b also might fall just within the outer edge of its star’s “habitable zone,” the orbital distance that could allow liquid water to form on the planet’s surface under a suitable atmosphere.
这颗行星的轨道周期（被列为“候选行星”，有待进一步确认）可能与地球相似，约为一年。 HD 137010 b 行星也可能恰好落在其恒星“宜居带”的外缘内，该轨道距离可以让液态水在合适的大气层下在行星表面形成。
Planets orbiting other stars are known as “exoplanets.” And this could turn out to be the first exoplanet with Earth-like properties that, from our vantage point, crosses the face of a Sun-like star that is near enough and bright enough for meaningful follow-up observations.
绕其他恒星运行的行星被称为“系外行星”。这可能是第一颗具有类似地球特性的系外行星，从我们的有利位置来看，它穿过一颗类太阳恒星的表面，该恒星足够近且足够明亮，可以进行有意义的后续观测。
Now the bad news. The amount of heat and light such a planet would receive from its star is less than a third of what Earth receives from the Sun. Although of a stellar type similar to our Sun, the star, HD 137010, is cooler and dimmer. That could mean a planetary surface temperature no higher than minus 90 degrees Fahrenheit (minus 68 degrees Celsius). By comparison, the average surface temperature on Mars runs about minus 85 degrees Fahrenheit (minus 65 degrees Celsius).
现在是坏消息。这样的行星从其恒星接收到的热量和光量还不到地球从太阳接收到的热量和光量的三分之一。虽然 HD 137010 的恒星类型与太阳相似，但它的温度较低且较暗。这可能意味着行星表面温度不高于-90华氏度（-68摄氏度）。相比之下，火星的平均表面温度约为-85华氏度（-65摄氏度）。
Planet HD 137010 b also will need follow-up observations to be promoted from “candidate” to “confirmed.” Exoplanet scientists use a variety of techniques to identify planets, and this discovery comes from a single “transit” — only one instance of the planet crossing its star’s face in a kind of miniature eclipse — detected during Kepler’s second mission, known as K2. Even with just one transit, the study’s authors were able to estimate the candidate planet’s orbital period. They tracked the time it took for the planet’s shadow to move across the star’s face — in this case 10 hours, while Earth takes about 13 — then compared it to orbital models of the system itself. Still, though the precision of that single detection is much higher than most transits captured by space-based telescopes, astronomers need to see these transits repeat regularly in order to confirm that they are caused by a real planet.
HD 137010 b 行星还需要后续观测才能从“候选”升级为“确认”。系外行星科学家使用多种技术来识别行星，而这一发现来自于开普勒第二次任务（称为 K2）期间发现的一次“凌日”——只有一个行星在一种微型日食中穿过恒星表面的实例。即使只有一次凌日，该研究的作者也能够估计候选行星的轨道周期。他们追踪了行星阴影穿过恒星表面所需的时间（在本例中为 10 小时，而地球大约需要 13 小时），然后将其与系统本身的轨道模型进行了比较。尽管如此，尽管单次探测的精度远高于天基望远镜捕获的大多数凌日现象，但天文学家需要定期观察这些凌日现象的重复，以确认它们是由真实的行星引起的。
And capturing more transits is going to be tricky. The planet’s orbital distance, so similar to Earth’s, means such transits happen far less often than for planets in tighter orbits around their stars (it’s a big reason why exoplanets with Earth-like orbits are so hard to detect in the first place). With luck, confirmation could come from further observation by the successor to Kepler/K2, NASA’s TESS (the Transiting Exoplanet Survey Satellite), the still-functioning workhorse for planetary detection, or from the European Space Agency’s CHEOPS (CHaracterising ExOPlanets Satellite). Otherwise, gathering further data on planet HD 137010 b might have to wait for the next generation of space telescopes.
捕捉更多的凌日现象将会很棘手。这颗行星的轨道距离与地球非常相似，这意味着这种凌日发生的频率远低于围绕恒星运行的更紧密轨道的行星（这就是为什么具有类似地球轨道的系外行星很难被发现的一个重要原因）。运气好的话，可以通过开普勒/K2的后继者、美国宇航局的TESS（凌日系外行星勘测卫星）（仍在运行的行星探测主力卫星）或欧洲航天局的CHEOPS（系外行星特征卫星）的进一步观测来证实。否则，收集 HD 137010 b 行星的进一步数据可能需要等待下一代太空望远镜。
Despite the possibility of a frigid climate, HD 137010 b also could turn out to be a temperate or even a watery world, say the authors of the paper on this exoplanet. It would just need an atmosphere richer in carbon dioxide than our own. The science team, based on modeling of the planet’s possible atmospheres, gives it a 40% chance of falling within the “conservative” habitable zone around the star, and a 51% chance of falling within the broader “optimistic” habitable zone. On the other hand, the authors of the study say the planet has about a 50-50 chance of falling beyond the habitable zone entirely.
关于这颗系外行星的论文作者表示，尽管 HD 137010 b 可能存在寒冷气候，但它也可能是一个温带世界，甚至是一个水世界。它只需要一个比我们自己的二氧化碳含量更丰富的大气层。科学团队根据对行星可能大气层的建模，得出其有 40% 的可能性落在恒星周围的“保守”宜居带内，有 51% 的可能性落在更广泛的“乐观”宜居带内。另一方面，该研究的作者表示，这颗行星有大约 50-50 的机会完全脱离宜居带。
An international science team published a paper on the discovery, “A Cool Earth-sized Planet Candidate Transiting a Tenth Magnitude K-dwarf From K2,” in The Astrophysical Journal Letters on Jan. 27, 2026. The team was led by astrophysics Ph.D. student Alexander Venner of the University of Southern Queensland, Toowoomba, Australia, now a postdoctoral researcher at the Max Planck Institute for Astronomy, Heidelberg, Germany.
一个国际科学团队于 2026 年 1 月 27 日在《天体物理学杂志快报》上发表了一篇关于这一发现的论文，“一颗酷地球大小的候选行星从 K2 转变为十级 K 矮星”。该团队由天体物理学博士领导。澳大利亚图文巴南昆士兰大学的学生亚历山大·文纳 (Alexander Venner)，现为德国海德堡马克斯·普朗克天文学研究所的博士后研究员。
Other authors include several volunteers from NASA’s Planet Hunters citizen science project — Hans Martin Schwengeler, Martti H. Kristiansen, Mark Omohundro, and Ivan A. Terentev. Veneer also participated in the Planet Hunters project before he completed his Ph.D.
其他作者包括来自美国宇航局行星猎人公民科学项目的几位志愿者——汉斯·马丁·施文格勒、马蒂·H·克里斯蒂安森、马克·奥莫亨德罗和伊万·A·特伦捷夫。在完成博士学位之前，Veneer 还参与了行星猎人项目。