JUPITERASC
Well-known member
JUPITERASC: Basically, you seem to be saying that tropical solar returns should be measured by exact house position at birth time and that sidereal returns should be measured according to position against the stars. If this is what you're saying, I am in full agreement.
As to the differences between tropical and sidereal returns, the differences you describe are basically the same as those between a synodic lunar month and a sidereal lunar month. Information can be derived from the synodic measurement (i.e. phases of the Moon) and from the sidereal measurement (e.g. lunar mansions). Both are valid in their own context. Which measurement you should use depends on what information you're trying to derive.
tsmall: The precession of the Earth is made to seem irregular by a number of wobbles, including the one you mentioned. Modern methods can measure these wobbles with impressive precision, but still nowhere near what we would need to accurately predict the nuances of the Earth's spinning thousands of years in advance. We're still unable to prove a solid mean or average for the spin because of these gaps in our knowledge. It's also true that the top (and the Earth) will wobble more as it slows (exaggerating the effect over time). We also know that large seismic/volcanic events can change the shape of the Earth enough to effect its rotation, creating what might be called "noise in the system."
We think precession is largely due to these wobbles causing the Earth to move more to cover the same amount of space. This doesn't cause as much deceleration as one might think. It just makes each year take a little longer and it means that every year is slightly different in length. The ancient literature, according to my forgotten source, says that the proper ayanamsa will continue decreasing for thousands of years. If that represents a reversed precession, then the sky would start drifting forward instead of backward. Even if the Earth were a perfect system, the sky still shouldn't drift forward. The only way that makes sense is if the spin of the Earth is actively accelerated somehow and the effect should only last as long as the acceleration does. I have no idea how such a thing would happen, but I won't rule it completely impossible.
Some recent evidence confirming what you have said regarding seismic events is available at this link
http://content.usatoday.com/communi...thquake-shifted-earth-axis-shorter-day-nasa/1
QUOTE: The 9.0 magnitude earthquake that ravaged Japan also shortened Earth's day by just over one-millionth of a second (1.8 microseconds to be exact), according to NASA. It also shifted the Earth's axis by about 6.5 inches.