The four new stamps mark the 100th anniversary of the British Astronomical Association.
这四枚新邮票是为了纪念英国天文协会成立100周年而发行的。
There are differences between historical and astronomical numbering of years.
在历史的年代数目和天文年代数目之间存在差别.
The mathematical material is presented in chapters of work on astronomy.
数学材料是夹在天文著作的篇章里讲述的.
Astronomical research began to spread over the whole range of electromagnetic waves.
天文研究开始向整个电磁波谱范围延拓.
It leads to the dramatic advances in astronomical photography.
天文照相术得到巨大发展.
It is called celestial navigation.
它叫做天文导航.
Our astronomical work is handicapped just now.
目前我们的天文工作受到阻碍.
The trivium consisted of grammar, logic and rhetoric, the quadrivium of arithmetic, geometry, astronomy and music.
三门科目由文法 、 逻辑和修辞学组成;四门科目由算术 、 几何 、 天文和音乐组成.
These mixtures of astronomical instruments and time - measuring devices cannot be seen as independent time measurers.
这类计时器尚不能算是独立的计时器,还是天文仪器与计时仪器的混合体.
It will be of great importance in fields such as astronomical observation and longrange navigation.
这在一些领域,如天文观测、远航等,具有十分重要的意义.
The reasons why ancient people studied the sky are as intriguing as how they did it.
古人研究天文的理由以及他们怎样去做,同样是难解的.
The unsteady air is the most dangerous source of disturbance for astronomical photography.
不稳定的空气便是天文照相最危险的干扰源.
Arithmetic, geometry, and astronomy were considered the art of the mind and music for the soul.
算术 、 几何和天文被看作是心智的艺术和灵魂的音乐.
Using Greek sources, he compiled in Latin selections from elementary treatises on arithmetic, geometry, and astronomy.
他根据希腊材料用拉丁文选编算术 、 几何与天文的初等读物.
Common fractions written in the Greek or Egyptian system were too awkward for astronomical calculations.
用希腊人或埃及人那套办法写出来的普通分数很不便于作天文计算.