The full ZB18a solution spans the past 100 Myr.
It contains the HNBody output of Zeebe & Lourens (2019) after some pre-processing using
prepare_solution(). The wikipedia page on Orbital elements describes what the
components relate to in order to uniquely specify an orbital plane.
Format
get_solution("full-ZB18a")
A data frame with 250,001 rows and 20 columns:
- t
Time \(t\) (days).
- time
Time in thousands of years (kyr).
- aa
Semimajor axis \(a\) in astronomical units (au).
- ee
Eccentricity \(e\) (unitless).
- inc
Inclination \(I\) (degrees).
- lph
Longitude of perihelion \(\varpi\) (degrees).
- lan
Longitude of the ascending node \(\Omega\) (degrees).
- arp
Argument of perihelion \(\omega\) (degrees).
- mna
Mean anomaly \(M\) (degrees).
The following columns were computed from the above input with prepare_solution():
- lphu
Unwrapped longitude of perihelion \(\varpi\) (degrees without jumps).
- lanu
Unwrapped longitude of the ascending node \(\Omega\) (degrees without jumps).
- hh
Variable: \(e\sin(\varpi)\).
- kk
Variable: \(e\cos(\varpi)\).
- pp
Variable: \(2\sin(0.5I)\sin(\Omega)\).
Variable: \(2\sin(0.5I)\cos(\Omega)\).
- cc
Helper: \(\cos(I)\).
- dd
Helper: \(\cos(I)/2\).
- nnx, nny, nnz
The \(x\), \(y\), and \(z\)-components of the Eart's orbit unit normal vector \(\vec{n}\), normal to Earth's instantaneous orbital plane.
Source
All astronomical solutions by Zeebe can be found on http://www.soest.hawaii.edu/oceanography/faculty/zeebe_files/Astro.html.
They can be loaded into R quickly, using get_solution().
References
Zeebe, R. E., & Lourens, L. J. (2019). Solar System chaos and the Paleocene–Eocene boundary age constrained by geology and astronomy. Science, 365(6456), 926–929. doi:10.1126/science.aax0612 .
Zeebe, R. E. and Lourens, L. J. (2022). A deep-time dating tool for paleo-applications utilizing obliquity and precession cycles: The role of dynamical ellipticity and tidal dissipation. Paleoceanography and Paleoclimatology. doi:10.1029/2021PA004349