Speaker
Description
For billions of years, the celestial sphere has acted as a universal clock and reliable map for life on Earth. As a result, many terrestrial species have evolved to regulate their biological functions and behaviors by the regular cycles of sunlight and moonlight (i.e., photocycles) and navigate by recognizable patterns in the night sky. These celestial patterns and cycles are so fundamentally intertwined with life that many species have come to depend on them at a molecular level, with genes known to regulate biological functions and behaviors according to the solar day and lunar month.
Near-term spaceflight activities have the potential to significantly disrupt these natural patterns and photocycles, with unknown consequences for Earth's biosphere. This is not a hypothetical or far-off problem, as rapidly decreasing launch costs and accelerating technological innovation are opening up outer space to an increasingly diverse array of human activity. Notably, several companies are actively pursuing plans to display advertising, entertainment, and art from low Earth orbit, while government-sponsored initiatives such as space-based solar power seek to place structures of unprecedented size and brightness in orbit.
This talk will discuss the links between human activity in space and Earth’s biosphere, primarily via spaceflight’s impact on the patterns and photocycles that characterize the celestial sphere. It will be argued that environmental impact studies of spaceflight must be expanded to assess spaceflight’s impact on Earth’s biosphere not only during launch and reentry but also while in space.
