View Single Post
Dec2-09, 07:03 PM
Sci Advisor
HW Helper
P: 8,953
Quote Quote by woolf View Post
The Mayan calendar comes to an end (in linear counting mode) in 2012. However, the calendar itself is a circle and the Mayans thought in this circular pattern,
It doesn't end it just clocks around a new leading digit (from 12 to 13), it last did this in the 17th century and nothing happened.

Crossing the galactic plane is speculation, but also a cyclic event.
Not speculation, our orbit around the galaxy is inclined - we must cross the plane twice in each rotation.

The concern from some theorists is that the "plane" transit is related to our magnetic field shift, which is also a cyclic pattern.
Apart from the complete lack of any mechanism to link these, the galactic orbit period is 220Myr and very regular.
Magnetic field reversals are not at all regular (and are probably chaotic) but occur at an interval of < 1Myr.

Since we've only inhabited this rock as semi-sentient beings for a short time, we have yet to experience that effect first-hand.
But lots of other species have and don't seem to have been over worried.