You observe the planet Saturn at a sextant...

Question 1 of 2707066636eea28f7522a1c51b416

You observe the planet Saturn at a sextant altitude (hs) of 63° 05.1' on 25 May. The index error is 4.5' off the arc. The height of eye is 62 feet. What is the observed altitude (Ho)?

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Question 1 of 27070

You observe the planet Saturn at a sextant altitude (hs) of 63° 05.1' on 25 May. The index error is 4.5' off the arc. The height of eye is 62 feet. What is the observed altitude (Ho)?

🔍 Key Concepts

• Index correction: How to apply a sextant index error that is "off the arc" to get the index correction and corrected sextant altitude • Dip (height of eye) correction: How to convert height of eye in feet to dip and whether it is added or subtracted • Order of corrections when converting hs → Ha → Ho (sextant altitude to apparent altitude to observed altitude)

💭 Think About

• First, decide whether an index error that is "off the arc" makes the index correction positive or negative, and whether that correction is added to or subtracted from hs • Convert the 62‑foot height of eye into a dip correction using the standard sight-reduction tables or formula, then determine if dip is always added or always subtracted • After applying both index correction and dip (and remembering that for a planet, refraction and semidiameter are handled per tables), compare which multiple-choice value is closest to your final Ho

✅ Before You Answer

• Be sure the sign of the index correction is correct for "off the arc" (this is a common exam trap) • Confirm that the dip correction is in minutes of arc and that you used height in feet, not meters • Check that you applied corrections in the right direction: index correction first, then dip, then any other small corrections for a planet before matching to the choices