OFM - Lecture 1-3

Question 1

What is the reference point of Earth?

Answer 1

First point of aries aka vernal point

Question 2

Name the reference frames and their origins

Answer 2

• Heliocentric (Origin = Sun)
• Geocentric (Origin = Earth)
• Barycentric (Origin = gravity Planet-Sun or Planet-Moon)
• Topocentric (Origin = observation point)

Question 3

what is the ecliptic?

Answer 3

The ecliptic is essentially the plane of Earth’s orbit projected outwards onto the celestial sphere. It represents the average plane of Earth’s orbit around the Sun.