Living in a Dying Solar System, Part 2: Delaying Doomsday With
this essay by Ray Villard, news director for the Hubble Space
Telescope, Astrobiology Magazine presents another in our series
of 'Gedanken', or thought, experiments - musings by noted
scientists on scientific mysteries in a series of "what if"
scenarios. Gedanken experiments, which have been used for
hundreds of years by scientists and philosophers to ponder
thorny problems, rely on the power of one's imagination to
project these scenarios to logical conclusions. They do not
involve lab equipment or, often, even experimental data. They
can be thought of as focused daydreams. Yet, as in the famous
case of Einstein's Gedanken experiments about what it would be
like to hitch a ride on a light wave, they have often led to
important scientific breakthroughs. Earth’s ultimate fate 5
billion years from now is a death spiral into the Sun. As the
Sun ages, its gravitational pull will weaken, and Earth will
briefly migrate out to the distance of Mars’ orbit