12月8日，水星西大距上演，这也是今年最后一次观测水星的机会。下次再看到水星就是明年2月 了。 今年双子座流星雨极大时间落在12月14日上午，因此13日夜晚至14日凌晨最适合观赏。天文馆专家 说，双子座流星雨是每年三大流星雨中最稳定、流量最高的流星雨，每年天顶流量都能达到约150的峰 值。冬季夜晚温度很低，观测者要做好保暖措施。 月掩昴星团陪伴我们度过本年最后一天。12月31日21至22时，月亮来到昴星团身边。不过，此时月 光很强，掩盖了昴星团中星星的光辉，感兴趣的天文爱好者可以尝试用望远镜拍摄。 央视网消息：据"北京发布"公众号消息，12月5日凌晨，我们将迎来今年最后一次近地点满月，也 就是"超级月亮"。北京天文馆专家介绍，4日晚观测更佳。 由于月球的公转轨道是个椭圆，月球与地球距离大约在36万到40万千米之间变化，由此带来的月球 视直径也在发生变化，最大和最小的满月直径相差大约14%。这个差异普通人用肉眼很难察觉，训练有 素的观测者能感到不同满月的大小。 ...

Core Points - Mercury will have its best observation opportunity during the western elongation on August 19, 2023, with favorable conditions for the public to view the planet if the weather permits [1][4] - Mercury is the hardest planet to observe due to its proximity to the Sun, often being obscured by sunlight [2] - The best time to observe Mercury is during its greatest angular distance from the Sun, known as "greatest elongation," which occurs approximately every 116 days [2][4] Observation Conditions - This western elongation will allow Mercury to be seen in the eastern low sky during dawn, with a horizon height of about 18 degrees and a brightness of 0 magnitude [4] - Observers using telescopes may also see Mercury in a crescent shape, with approximately 40% of its surface illuminated by the Sun [4] - The observation opportunity is not limited to August 19; several days before and after also provide chances to view Mercury due to minimal height variation [7]

Core Viewpoint - The article discusses the upcoming western elongation of Mercury on August 19, which presents the best observation conditions for the planet this year, allowing the public to potentially view it in the early morning sky if weather permits [1][2]. Group 1: Observation Conditions - Mercury will be at a horizontal height of approximately 18 degrees at sunrise, with a brightness of 0 magnitude, making it visible to the public [2]. - The observation of Mercury is not limited to August 19; the days surrounding this date also provide good opportunities for viewing due to minimal changes in the planet's height [3]. Group 2: Characteristics of Mercury - Mercury is the most challenging planet to observe in the solar system due to its proximity to the Sun, often being obscured by sunlight [1]. - The planet completes its orbit around the Sun in just 88 days, resulting in 3 to 4 occurrences of both eastern and western elongations each year, with varying observation conditions based on its position relative to the Sun [1].

Core Points - Mercury will have its eastern elongation on July 4, 2023, providing good observation conditions for the public if the weather is clear [1][2] - Mercury is the closest planet to the Sun and is difficult to observe due to its proximity to the Sun's glare [1] - The best time to observe Mercury is during its eastern elongation when it appears in the western sky after sunset [1] Observation Conditions - This year, Mercury will have three eastern elongations, occurring on March 8, July 4, and October 30, with the first two having favorable observation conditions [2] - On July 4, Mercury's altitude will be approximately 18 degrees at sunset, with a brightness of about 0.4 magnitude [2] - Observers are encouraged to look for Mercury a few days before and after July 4, as the altitude will be higher in the days leading up to the event [2]