4000颗系外行星

2022年8月14日

4000 Exoplanets
Video Credit: SYSTEM Sounds (M. Russo, A. Santaguida); Data: NASA Exoplanet Archive

Explanation: Over 4000 planets are now known to exist outside our Solar System. Known as exoplanets, this milestone was passed last month, as recorded by NASA’s Exoplanet Archive. The featured video highlights these exoplanets in sound and light, starting chronologically from the first confirmed detection in 1992 and continuing into 2019. The entire night sky is first shown compressed with the central band of our Milky Way Galaxy making a giant U. Exoplanets detected by slight jiggles in their parents-star’s colors (radial velocity) appear in pink, while those detected by slight dips in their parent star’s brightness (transit) are shown in purple. Further, those exoplanets imaged directly appear in orange, while those detected by gravitationally magnifying the light of a background star (microlensing) are shown in green. The faster a planet orbits its parent star, the higher the accompanying tone played. The retired Kepler satellite has discovered about half of these first 4000 exoplanets in just one region of the sky, while the TESS mission is on track to find even more, all over the sky, orbiting the brightest nearby stars. Finding exoplanets not only helps humanity to better understand the potential prevalence of life elsewhere in the universe, but also how our Earth and Solar System were formed.

Tomorrow’s picture: wall of stars

4000颗系外行星
影片提供: SYSTEM Sounds (M. Russo, A. Santaguida); 数据: NASA Exoplanet Archive

说明: 在我们太阳系的外头，目前已找到超过4,000颗通称为系外行星的天体。根据美国国家航空航天局的系外行星资料库，这个里程碑达成于2019年6月。上面这部主题影片，以1992年第一次确认侦测为起点，依照发现的时间序，以声和光突显这些系外行星。影片首先呈现整个经过压缩的夜空，在其中，我们的中央盘面形似一庞大的U字。由量测母星色泽（径向速度）受到的轻微扰动，所侦测到的系外行星以粉红标示，侦测母星亮度（凌星）的微量下降，而侦测到的系外行星以紫色标示。因直接成像而发现的系外行星为橙色， 由于系外行星的重力对背景恒星造成的星光放大（微重力透镜）而现踪的，以绿色标示。此外，行星绕行母星越快者，对应的音阶越高昂。目前已除役的开普勒太空望远镜，在一个小小的天区里，就约找到头4,000颗系外行星之半，而接棒的TESS（凌星系外行星巡天望远镜）计画，预期会在所有的天区，找到更多绕行邻近最明亮恒星的系外行星。寻找系外行星，不但有助于人类深入了解宇宙其它地方的生命到底有多常见，也可厘清我们的地球和太阳系是如何形成的。

明日的图片: wall of stars