月亮飞船的:宇宙探秘
Two Suns Set on Alien World
by Govert Schilling 胡德良 译
| Astronomers have discovered the first planet that, like Luke Skywalker's fictional home world in Star Wars, orbits two suns. The stars are a binary pair: They are about 1.5 and 4.5 times smaller than our own sun, and they orbit each other every 41 days, causing brightness dips that have been detected by the Kepler space telescope. Kepler also spied additional dips, produced when a Saturn-sized planet transits across the stars every 229 days. Both stars and planet orbit in the same plane, suggesting they formed together from a single spinning disk of gas and dust, researchers report today in Science. Until now, astronomers weren't sure whether or not planets would be able to form around binary stars. In particular, they thought that when the stars were in an eccentric orbit, as is the case here, they would strongly perturb dust particles that might prevent their coalescence into larger bodies. Kepler was lucky to find the Tatooine planet: Because of our slowly changing view of the system, there will be no planetary transits visible between 2018 and 2042. | 天文学家们发现了第一颗环绕两颗恒星的行星，如同《星球大战》中为卢克·天行者虚构的作为家园的星球一样。这两颗恒星是一对双星：它们大约比我们的太阳分别小1.5倍和4.5倍，每隔41天互相环绕一周，所引起的亮度变暗现象被开普勒太空望远镜探测到。开普勒望远镜还探测到其他的变暗现象：一颗土星大小的行星每隔229天在两颗恒星前面经过时产生的变暗现象。今天，研究人员在《科学》杂志上报道说，两颗恒星和该行星位于同一平面上，表明它们一起形成于同一个旋转的气体尘埃圆盘中。此前，天文学家们不能确定行星是否能够形成于双星周围。他们认为，特别是当恒星像该系统的情况一样处于奇怪的轨道上时，会大大地扰动尘埃粒子，阻碍尘埃粒子聚结成较大的天体。开普勒望远镜发现了这颗“塔图音”式的行星是幸运的：对于这个系统来说，我们的视野变更很慢，因此在2018年至2042年之间不看到行星凌日的现象。 |
译自：美国《科学》杂志网站（15 September 2011, 2:00 PM）
原著：Govert Schilling
庭院结构设计
评论