You observe the star Antares at a sextant altitude (hs) of 38°18.7' on 28 February. The index error is 2.4' on the arc. The height of eye is 40 feet (12.2 meters). What is the observed altitude (Ho)?

Question

You observe the star Antares at a sextant altitude (hs) of 38&deg;18.7' on 28 February. The index error is 2.4' on the arc. The height of eye is 40 feet (12.2 meters). What is the observed altitude (Ho)?

Accepted Answer

Option B: 38&deg;09.0'. Applying celestial reduction corrections per Bowditch: index error 'on the arc' is subtracted, dip for a 40-foot height of eye is subtracted, and standard refraction correction is applied to determine observed altitude 38&deg;09.0'.

You observe the star Antares at a sextant altitude (hs) of 38&deg;18.7' on 28 February. The index error is 2.4' on the arc. The height of eye is 40 feet (12.2 meters). What is the observed altitude (Ho)?

You observe the star Antares at a sextant altitude (hs) of 38°18.7' on 28 February. The index error is 2.4' on the arc. The height of eye is 40 feet (12.2 meters). What is the observed altitude (Ho)?