China T109, Return of Halley’s Comet (1985-1986)《哈雷彗星回归》
T109 哈雷彗星回归
(1-1) 哈雷慧星回归,20分,2811.9万枚
发行日期：1986.4.11
设计：袁加
印刷：北京邮票厂
哈雷彗星是以英国著名天文学家埃德蒙·哈雷命名的周期彗星。彗星与九大行星一样，都是围绕太阳运转的行星，已被人类发现的有1600多个。在众多的彗星中，哈雷彗星最负盛名。哈雷彗星形状很特别，远离太阳时是一个发光的雾状小斑点，接近太阳时呈现为彗核、彗发、彗尾三个部分。彗核与彗发总称彗头，体积庞大。当彗星在回归中接近太阳的时候，表层的物质受热后气化，开始蒸发，反射阳光，形成包在彗核周围的明亮的彗发。拖在后面的彗尾，则由稀薄的气体和尘埃组成，形状像扫帚，朝着背向太阳的方向延伸，可长达数千万甚至上亿公里。
主图为哈雷彗星拖着长长的尾巴在飞行，下部为呈弧形的地球一侧，中间如文字般排列着四幅长沙马王堆汉墓帛书上的彗星图，这是迄今为止所发现的世界上最早的彗星图。背景为暗蓝色的宇宙。“彗”在中文中有扫帚的意思。中国古代就是根据该星有一条长长的扫帚形尾巴而为它取名的，俗称“妖星”、“扫帚星”。中国在公元前7世纪时对彗星已有观测。天文学家根据有关资料，证明周武王伐纣时出现的彗星，就是公元前1057年回归的哈雷彗星。从“牧野之战”迄今的3000年中，中国共有32次关于哈雷彗星行踪的纪录。
Stamp Title: Return of Halley’s Comet (1985-1986)
Serial number: T109
Date of issue: April 11, 1986
Designers: Yuan Jia
Printing House: Beijing Postage Stamp Printing Works
Edmund Halley was an English scientist who lived over 200 years ago. He studied the observations of comets which other scientists had made. The orbit of one particular comet was a very difficult mathematical problem. He could not figure it out. Neither could other scientists who dealt with such problems.
However, Halley had a friend named Newton, who was a brilliant mathematician. Newton thought he had already worked out that problem but he could not find the papers on which he had done it. He told Halley that the orbit of a comet had the shape of an ellipse.
Now Halley set to work. He figured out the orbits of some of the comets that had been observed by scientists. He made a surprising discovery. The comets that had appeared in the years 1531, 1607, and 1682 all had the same orbit. Yet their appearances had been 75 to 76 years apart.
This seemed very strange to Halley. Three different comets followed the same orbit. The more Halley thought about it, the more he thought that there had not been three different comets, as people thought. He decided that they had simply seen the same comet three times. The comet had gone away and had come back again.
It was an astonishing idea Halley felt certain enough to make a prediction of what would happen in the future. He decided that this comet would appear in the year 1758. There were 53 years to go before Halley’s prediction could be tested.
In 1758 the comet appeared in the sky. Halley did not see it, for he had died some years before. Ever since then that comet has been called Halley’s comet, in his honor.
