You observe the lower limb of the Sun at a sextant altitude (hs) of 35°26.3' on 25 June. The index error is 1.5' on the arc. The height of eye is 58 feet (17.6 meters). What is the observed altitude (Ho)?

Question

You observe the lower limb of the Sun at a sextant altitude (hs) of 35&deg;26.3' on 25 June. The index error is 1.5' on the arc. The height of eye is 58 feet (17.6 meters). What is the observed altitude (Ho)?

Accepted Answer

Option C: 35&deg;32.1'. According to Bowditch, subtract index error 'on the arc' and height of eye dip (58 ft) from sextant altitude. Adding the nautical almanac solar semidiameter and applying altitude refraction results in an observed altitude of 35&deg;32.1'.

You observe the lower limb of the Sun at a sextant altitude (hs) of 35&deg;26.3' on 25 June. The index error is 1.5' on the arc. The height of eye is 58 feet (17.6 meters). What is the observed altitude (Ho)?

You observe the lower limb of the Sun at a sextant altitude (hs) of 35°26.3' on 25 June. The index error is 1.5' on the arc. The height of eye is 58 feet (17.6 meters). What is the observed altitude (Ho)?