How do I establish the location of L3?

Question

1 a) How do I establish the location of L3?
1 b) Which is nearer Earth, L3 or the Moon?

2 a) What is "oblique ascension"?
2 b) How might an understanding of oblique ascension be of practical use
to an observational amateur astronomer?

I'm trying to get an understanding of L3 's when reading about orbits on the internet ..some facts i'm trying to understand .

thanks in advance

Answer 1

Hi. The L points are just names. You should really try to understand how the gravity balances at these points and why objects in them tend to stay in them. Oblique ascension is also just a name. The points on the Celestial Equator (an imaginary circle 90 degrees from the Earth's axis) that crosses the plane in which the Earth orbits the Sun, and where the length of days and nights are roughly equal, simply provide a starting point for locating objects along that plane.