claim: Also, it is increasingly clear that the planet was significantly warmer than today several times during the past 10,000 years.
evidence: The oscillation in the Z direction takes the Sun ( W ( 0 ) ν ) 2 + Z ( 0 ) 2 = 98  parsec {\displaystyle {\sqrt {\left({\frac {W(0)}{\nu }}\right)^{2}+Z(0)^{2}}}=98{\text{ parsec}}} above the galactic plane and the same distance below it, with a period of 2 π / ν {\displaystyle 2\pi /\nu } or 83 million years, approximately 2.7 times per orbit.