Apparent altitude is sextant altitude...

Apparent altitude is sextant altitude...

Question 1 of 2707066636ee928f7522a1c51913e

Apparent altitude is sextant altitude corrected for __________.

Question 1 of 27070

Q

Apparent altitude is sextant altitude corrected for __________.

🔍 Key Concepts

• sextant altitude (Hs) vs. apparent altitude (Ha) vs. true altitude (Ho) • Which errors are removed first when you start with the raw sextant reading • The difference between instrument/observer errors and physical/astronomical corrections

💭 Think About

• When you take an angle with a sextant, what are the very first corrections you normally apply to the raw Hs before you worry about the Earth, atmosphere, or the body itself? • Which of the listed options are actually properties of the celestial body (like brightness) or conditions of the atmosphere, and which are caused by the sextant or the observer? • Think about the standard sight‑reduction sequence: Hs → Ha → Ho. Which step (Hs → Ha or Ha → Ho) includes things like dip, refraction, semidiameter, and which one focuses on cleaning up the sextant reading itself?

✅ Before You Answer

• Identify which choice(s) refer to instrument/observer errors (e.g., index error, personal error) rather than physical/astronomical effects • Recall that apparent altitude (Ha) is an intermediate step; not all corrections are applied at once • Verify which corrections belong in the later step going from apparent altitude to true altitude (those should NOT be included in this answer)