半直径

The semidiameter of the moon can be measured with relative ease using basic astronomical tools.
月球的半径可以通过使用基本的天文工具相对容易地测量。
The apparent semidiameter of the sun varies throughout the year due to the Earth's elliptical orbit.
由于地球沿椭圆轨道运行，太阳的视半径在一年中会发生变化。
In calculating the volume of a sphere, the formula involves squaring the radius, which is effectively the semidiameter.
计算球体体积的公式涉及半径（即半直径）的平方。
Observations of celestial bodies often require precise measurements of their semidiameters for astronomical calculations.
对天体的观测常常需要对其半径进行精确测量，以便进行天文计算。
The semidiameter of a planet, as seen from Earth, depends on both the planet's actual size and its distance from us.
从地球上看，行星的半径取决于行星的实际大小以及它与我们的距离。
Astronomers use the term 'semidiameter' when referring to the apparent linear size of a celestial object's disc.
天文学家在提及天体盘面的视线性尺寸时，会使用“半径”这个词。
Understanding the semidiameter of stars helps astronomers in classifying them based on their sizes and distances.
了解恒星的半径有助于天文学家根据它们的大小和距离对它们进行分类。
During a lunar eclipse, careful measurements of the moon's semidiameter can provide insights into Earth's atmosphere.
在月食期间，对月球半径的仔细测量可以提供有关地球大气层的信息。
In the study of planetary transits, the semidiameter of the transiting body is crucial for accurate timing and depth calculations.
在研究行星凌日现象时，穿越天体的半径对于准确的时间和深度计算至关重要。
The semidiameter of a comet's coma, though challenging to determine due to its diffuse nature, is important for understanding its composition.
尽管彗星彗发的半径由于其弥散的性质而难以确定，但它对于理解其组成非常重要。