If the right ascension of a body is 9 hours,...

🔍 Key Concepts

• Relationship between right ascension (RA) measured in hours and arc degrees on the celestial equator • How Greenwich Hour Angle (GHA) and sidereal hour angle (SHA) are measured (from which reference point and in what direction) • Whether RA is associated with eastern or western measurement on the celestial sphere

💭 Think About

• Convert 9 hours of right ascension into degrees using the standard time-to-arc relationship. What angle do you get? • Think about where right ascension starts (what reference meridian on the celestial sphere) and in which direction it is measured. Does that match how SHA is defined? • If a body has a certain right ascension, does that automatically tell you whether its geographic position (GP) is in the eastern or western hemisphere?

✅ Before You Answer

• Use the conversion 15° per hour of RA to check any RA-to-degree answers • Confirm whether RA and SHA are measured from the same reference point and in the same direction • Verify if RA alone is enough information to determine if a GP is in the western hemisphere, or if you also need GHA or longitude information

If the right ascension of a body is 9 hours, it also __________.

is 135°

corresponds to an SHA for the body of 45°

means that the GP of the body is in the western hemisphere

All of the above

🔍 Key Concepts

💭 Think About

✅ Before You Answer