This page has been validated.

[ 1. INTRODUCTION ]

About twenty years ago, rapid advances in technology led to the viability of light-emitting diodes (LEDs) as outdoor lighting. With compelling operational and economic reasons to make the shift from legacy gas-discharge systems, communities around the world began installing white LEDs as their lighting of choice. In time, the side effects of the vastly increased sky glow and blue-rich spectral distribution of white LEDs became apparent, negatively impacting not only ground-based professional and amateur astronomy but also casual appreciation of the sky, flora and fauna, and human health.

Today, we are in the initial years of an analogous watershed moment, this time not on the ground but in space. The rapid development of efficient and in one case reusable rockets by private-sector companies has made Earth orbit no longer the exclusive realm of national agencies like NASA, and a steadily increasing number of entities is now launching both people and hardware into space. The result is exponential growth in the density and variety of satellites at a wide range of altitudes. As the glowing nighttime landscape on Earth has been transformed over the past two decades, so the sky is now being similarly transformed.

It is incumbent on all who use space and the night sky as a resource — professional and amateur astronomers, satellite operators, policymakers, environmentalists, people who observe the night sky and who preserve their culture in stories in the stars, and more — to consider the myriad impacts on humanity of the industrialization of space and to establish a shared vision for the use of space that supports and respects all its users.

Many efforts today to address the impact of rapidly growing light domes over cities and towns are reactive to already-deployed networks of white LEDs. In the realm of low-Earth orbit (LEO), there is a window of opportunity — albeit narrow and closing — to address the impact of thousands of new satellites proactively. The SATCON workshops are meant to set the foundation for this work.

3