The phase correction should be applied to...

Question 1 / 2707066636ee928f7522a1c519e26

Question 1 of 2707066636ee928f7522a1c519e26

The phase correction should be applied to sights of Venus and Mars __________.

Question 1 of 27070

The phase correction should be applied to sights of Venus and Mars __________.

🔍 Key Concepts

• Phase correction in celestial navigation and when it is needed • Differences between observations of planets and stars • How the visible illuminated portion of a planet affects the observed altitude and sight reduction

💭 Think About

• Ask yourself: do Venus and Mars always appear fully illuminated like stars, or can they show phases like the Moon? How would that affect the center of light you are actually observing? • Consider whether the need for phase correction depends on the time of day or on the geometry between the Earth, the planet, and the Sun. • Think about whether altitude alone (e.g., below 25°) creates the need for a phase correction, or whether the correction is tied to the planet’s illumination and relative positions in the solar system.

✅ Before You Answer

• Verify whether phase is a property that depends on local observation conditions (day, twilight) or on planet–Sun–Earth geometry. • Check in your reference tables: is phase correction listed as something to be considered whenever Venus or Mars sights are worked, or only under certain observing times or altitudes? • Confirm whether the illumination fraction of the planet, not the observer’s clock or altitude cutoff, is what drives the need for this correction.

Question 1 of 27070

The phase correction should be applied to sights of Venus and Mars __________.

during day time observations only

during twilight observations only

at all times

when observed at altitudes of less than 25°

Question 1 / 2707066636ee928f7522a1c519e26

Question 1 of 2707066636ee928f7522a1c519e26

The phase correction should be applied to sights of Venus and Mars __________.

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Question 1 of 27070

The phase correction should be applied to sights of Venus and Mars __________.