New answers tagged orbit
6
The key concept is called Tidal locking. Earth's gravity forced the Moon to rotate in that way during the first few tens of millions of years after the Moon formed and then kept it that way.
The wikipedia page describes the mechanism:
Consider a pair of co-orbiting objects, A and B. The change in rotation rate necessary to tidally lock body B to the larger ...
0
Thank you to those people that have tried to help me with this, both back when I first posted the question, and later.
With the solid advice of @barrycarter in the comments, I looked into using the SPICE library to compute the positions of the various celestial bodies of interest.
After some reading, and further advice from NAIF themselves, I took it upon ...
2
That is part of this document: The Whole Chapter 8
5
I believe you are right, this is extracted from the "Explantory supplement to the Astronomical Almanac (2006?)" (although it might date back to the 1960s...)
For example a similar PDF document gives that citation.
The supplement is published in a separate binding from the main astronomical almanc and a new version is published each year. Finding ...
4
This link even gives you the algorithm to calculate: link here
Also, if you are comfortable with the VSOP, the VSOP2000 does have the moon data...
the ephemerides can be downloaded from here
4
There is a python package called Skyfield that loads, reads and interpolates the binary forms of the JPL Development Ephemerides or DEs for you, and does everything else you need to get the absolute best results possible from them. If you can use even a tiny bit of python then this would be the way to go rather than trying to figure out how to interpolate ...
2
Both effects are the result of sunlight being absorbed and re-radiated as heat. As this re-radiation (cooling) is not uniform, it results in kinematic effects (unbalanced recoil). However, the defining physical difference boils down to the Yarkovsky effect being a force and YORP effect being a torque. The former is applied to the objects barycenter, whilst ...
2
There are two distinct questions in your post. I'll answer the first one.
There is a slight misconception in your question. A supermoon isn't just when the Moon is a periapsis, but when it is at periapsis during a full moon. Since the orbital period of the Moon is not the same as the time between two full moons, supermoons don't occur every month.
(On a ...
9
The Moon's orbit about the Earth is only approximately elliptical. The Moon's orbit precesses both axially and nodally, and the eccentricity of the Moon's orbit varies.
That the Moon's orbit precesses axially means that perigee sometimes occurs when the Moon is close to new, sometimes when it is close to half-full, and sometimes when it is close to full. ...
5
The moon's orbit is elliptical. This is what the moon's orbit looks like from above (A is the Earth, and C is moon, c is the orbit of the moon around the Earth)
As you see with an eccentricity of 0.056 it doesn't get very close to Earth, but if you look carefully enough, there is some variation. The moon in the diagram is at apoapsis, as far from the Earth ...
Top 50 recent answers are included
