单项选择题
A.calculating amplitudes B.calculating great circle sailings by the Agiton method C.entering the Air Navigation Tables (Selected Stars) Pub 249 D.plotting on star finders
Planetary aberration is due，in part，to（）.A.refraction o...
单项选择题Planetary aberration is due，in part，to（）.
A.refraction of light as it enters the Earth's atmosphere B.rotation of the Earth on it's axis C.the body's orbital motion during the time required for its light to reach Earth D.a false horizon
Perihelion is the point where the Sun（）.A.is nearest to...
单项选择题Perihelion is the point where the Sun（）.
A.is nearest to the Earth B.is farthest from the Earth C.is on the opposite side of the Earth from the Moon D.and Moon and Earth are in line
Other than the Sun and Moon，the brightest object in the...
单项选择题Other than the Sun and Moon，the brightest object in the sky is（）.
A.Sirius B.Canopus C.Venus D.Jupiter
