Something very interesting here is that the "primary" methods use very different physical mechanisms.
Celestial mechanics
Dendrochronology (from tree-ring counting), ice layering, and sedimentary varves are all dependent on seasonal modulation, and that is the result of our planet's axial tilt (obliquity).
Milankovitch astronomical cycles are the result of the planets perturbing each others' orbits, giving them varying orbit eccentricity and perihelion direction, and also varying inclination and node direction relative to the Solar System's "invariable plane" (perpendicular to its angular-momentum vector). This makes our planet's perihelion go through the seasons somewhat faster than spin precession alone would make it do, and this also makes the obliquity wobble a little bit.
Spin precession relative to the stars has a period of about 25,700 years. The Milankovitch precession cycle is about 23,000 years, the obliquity cycle is about 41,000 years, and the precession cycle is modulated by eccentricity cycles with periods around 100,000 and 400,000 years.
The Baptistina family is one of several of
Asteroid family. These were likely produced by collisions or impacts that produced a large number of fragments. These then went into slightly different orbits, and these differences were then magnified by perturbations of their orbits, notably from Jupiter.
Radioactive decay
There are several kinds of radioactive decay:
- Quantum-mechanical tunneling: alpha particles, spontaneous fission, etc.
- Weak interactions: electrons and positrons (beta particles), electron capture
- Electromagnetic: gamma rays
Changes in the values of elementary-particle constants would make different changes in decay rates, because of differences in the decay mechanisms. But such changes have not been observed.
Stellar-structure calculations
Helioseismology, globular-cluster ages.
Doing these calculations requires knowledge of both nuclear-reaction rates and stellar-material opacities.
Cosmological distances
Relativistic jets, distant starlight
The
Cosmic distance ladder is composed of several distance methods, each one covering only a fraction of the total distance range, but each one overlapping some of the others. A key part of this method is standard candles, objects with presumably the same luminosity at different places, like certain variable stars and supernovae. Standard candles are calibrated by measuring the distances to the nearer ones, and these candles may in turn be used to calibrate farther ones.