Another example of how present rates are used to travel through time...
"
The biological and geological
future of the Earth can be
extrapolated based upon the estimated effects of several long-term influences. These include the
chemistry at the Earth's surface, the
rate of cooling of the planet's interior, the
gravitational interactions with other objects in the
Solar System, and a steady increase in the
Sun's luminosity. .......
Over time intervals of hundreds of millions of years, random celestial events pose a global risk to the
biosphere, which can result in
mass extinctions. These include impacts by
comets or
asteroids with diameters of 510 km (3.16.2 mi) or more, and the possibility of a massive stellar explosion, called a
supernova, within a 100-
light-year radius from the Sun, called a
Near-Earth supernova. Other large-scale geological events are more predictable. If the long-term effects of
global warming are disregarded,
Milankovitch theory predicts that the planet will continue to undergo
glacial periods at least until the
quaternary glaciation comes to an end. These periods are caused by
eccentricity, axial tilt, and precession of the Earth's orbit.
[10] As part of the ongoing
supercontinent cycle,
plate tectonics will probably result in a supercontinent in 250350 million years. Some time in the next 1.54.5 billion years, the axial tilt of the Earth may begin to undergo chaotic variations, with changes in the axial tilt of up to 90°.
During the next four billion years, the luminosity of the
Sun will steadily increase, resulting in a
rise in the solar radiation reaching the Earth. This will cause a higher rate of
weathering of
silicate minerals, which will cause a decrease in the level of
carbon dioxide in the atmosphere. In about
600 million years, the level of CO
2
will fall below the level needed to sustain
C3 carbon fixation photosynthesis used by trees. Some plants use the
C4 carbon fixation method, allowing them to persist at CO
2
concentrations as low as 10 parts per million. However, the long-term trend is for
plant life to die off altogether. The extinction of plants will be the demise of almost all animal life, since plants are the base of the food chain on Earth."
https://en.wikipedia.org/wiki/Future_of_the_Earth
On and on it goes.