朋友,你喜欢集邮吗?你体验过从这方寸之中学到很多知识的乐趣吗?如果有,愿与你共享,如果没有,那么你不妨试一试。宇航事业的发展是当今科技领域的一大课题。各国对此都倾注了很大的人力和物力,特别是一些工业发达国家。就是工业不太发达的国家也对这一事业的发展倾注了很大的注意力。这一点在方寸世界里有着明显的体现(见本期封底)。 Friend, do you like stamp collecting? Have you ever had the pleasure of learning a lot from this dimension? If so, would like to share with you, if not, then you may wish to give it a try. The development of aerospace industry is a major issue in today’s science and technology. All countries have poured a great deal of manpower and material resources into this regard, especially in some industrially developed countries. Even countries with less developed industries have also devoted a great deal of attention to the development of this undertaking. This is evident in the square world (see the back cover of this issue).