Good newsβwe have extra time before the Sun ends life on Earth
Itβs a bit worrying when a scientific paper begins, βHow long will life on Earth survive?β But in this caseβa study by Jacob HaqqβMisra of Blue Marble Space and Eric Wolf at the University of Colorado Boulderβthe billion-plus-year timeline under consideration shouldnβt cause you too much existential panic.
The context for this question is that we understand the Sun will brighten as it eventually matures into a red giant that swallows the Earth in a solar furnace. So, where along that 5 billion-year path will life on Earth, in fact, be cooked?
Weathering and the weather
This isnβt just a question of incoming radiation. Among the thermostat-like stabilizing feedback loops in Earthβs climate, the cycling of CO2 through the solid Earth is a major factor over timescales this long. The weathering of silicate rocks at the surface converts atmospheric CO2 into carbonate that ends up on the seafloor, where it can be subducted into the mantle with tectonic plates. (And eventually, it can cycle back out to the atmosphere through volcanoes.)


Β© NASA/GSFC/SDO