小行星法厄同的子女

2024年12月12日

Phaethon’s Brood
Image Credit & Copyright: Mikiya Sato (Nippon Meteor Society)

Explanation: Based on its well-measured orbit, 3200 Phaethon (sounds like FAY-eh-thon) is recognized as the source of the meteoroid stream responsible for the annual Geminid meteor shower. Even though most meteor shower parents are comets, 3200 Phaethon is a known and closely tracked near-Earth asteroid with a 1.4 year orbital period. Rocky and sun-baked, its perihelion or closest approach to the Sun is well within the orbit of innermost planet Mercury. In this telescopic field of view, the asteroid’s rapid motion against faint background stars of the heroic constellation Perseus left a short trail during the two minute total exposure time. The (faint) parallel streaks of its meteoric children flashed much more quickly across the scene. The family portrait was recorded near the Geminid meteor shower’s very active peak on 2017 December 13. That was just three days before 3200 Phaethon’s historic close approach to planet Earth. This year, the night of December 13 should again see the peak of the Geminid meteor shower, but faint meteors will be washed out by the bright light of the nearly full moon.

Watch: The 2024 Geminid Meteor Shower
Tomorrow’s picture: deep sky

小行星法厄同的子女
影像提供与版权: Mikiya Sato (Nippon Meteor Society)

说明: 依据精确的轨道测量，小行星法厄同（3200 Phaethon；读音为FAY-eh-thon）咸认是造成双子座流星雨的流星体流之源头。不过，大部分流星雨的母源是彗星，而3200法厄同却是一颗轨道周期1.4年、受到密切监控的近地小行星。这颗饱受太阳炙烤的石质小行星，最靠近太阳的近日点，深入最内围水星的轨道之内。在这幅总曝光时间为2分钟的望远镜影像里，由于相对英仙座背景暗星的快速运动，这颗小行星曳出了短短的光痕，而它产出的流星子女，则曳着明亮的平流浪星痕更高速的掠过视野。这幅家族照摄于2017年12月13日，时值双子流星雨当年很活跃的极大期之时，也是法厄同小行星运行到史上最靠近地球位置的前3天。今年英仙座流星雨的极大期仍然落在12月13日晚，不过届时月亮接近满相，明亮的月光会淹没许多较暗的流星。

观看: 2024年双子座流星雨
明日的图片: deep sky