航海英语天文航海章节练习(2018.02.18)

单项选择题
A parallax correction is NOT applied to observations of the（）.
A.stars
B.Moon
C.Sun
D.Planets
单项选择题
In low latitudes，a first quarter Moon will always rise at about（）.
A.sunrise
B.1200 LMT
C.sunset
D.2400 LMT
单项选择题
A large group of stars revolving around a center is known as a（）.
A.cluster
B.shower
C.constellation
D.galaxy
单项选择题
As observed from the Earth，the angle between lines from the Earth to the Sun and the Earth to an inferior planet is known as（）.
A.elongation
B.conjunction
C.opposition
D.quadrature
单项选择题
Because the actual center of some planets may differ from the observed center，the navigator applies a correction known as the（）.
A.phase correction
B.refraction correction
C.semidiameter correction
D.augmentation correction
单项选择题
In working out a local apparent noon sight for your latitude，you subtract the Ho from 90°. The 90°represents the angular distance from（）.
A.the equator to the elevated pole
B.your horizon to your zenith
C.your zenith to the elevated pole
D.the geographical position of the Sun to the elevated pole
单项选择题
A phase correction may be applicable to correct the sextant altitude correction of（）.
A.any star
B.the Sun
C.third magnitude stars only
D.some planets
单项选择题
A sextant having an index error that is off the arc has a（）.
A.positive correction
B.dip error
C.negative correction
D.semidiameter error
单项选择题
A correction for augmentation is included in the Nautical Almanac corrections for（）.
A.the Sun
B.the Moon
C.Venus
D.None of the above
单项选择题
A first magnitude star is（）.
A.2.5 times as bright as a second magnitude star
B.3 times as bright as a second magnitude star
C.5 times as bright as a second magnitude star
D.10 times as bright as a second magnitude star