  October 1957, and the successful launch of Sputnik 1 into Earth orbit, marked
the dawn of the Space Age. The first of the 'fellow travellers' - humanity's
first artificial satellite - orbited for a mere three months before re-entering
the Earth's atmosphere, though its mission paved the way for an era of
exploration that has endured to the present day. For many, a world without
satellites would be a difficult one to imagine. As a society, we have become
reliant on them for a vast array of services and applications. With a divine
view of large swathes of the Earth's surface, and the ability to relay signals
around its curvature, satellites have enabled the fast transfer of data on a
global scale, bypassing the challenges associated with ground-based
broadcasting, long-distance wiring, and so on. Positioning, Navigation and
Timing (PNT) satellites have revolutionised transportation by land, air, and
sea, while weather satellites enable scientists to monitor and warn of
large-scale phenomena as they develop in near real-time. Satellites have
extended the frontiers of observation: looking outwards, astronomers are able
to circumvent the Earth's atmosphere to look deeper into the cosmos than ever
before; looking inwards, patterns and processes that feed into general
circulation models can be monitored on a range of timescales, improving our
understanding of climate change. Satellites, and the services they provide, are
not going to disappear any time soon. That said, threats to satellite safety do
exist, and it is important that they be addressed as soon as possible to avoid
long-lasting damage to operations in the space domain. Nearly sixty-five years
on from the advent of human activity in space, I chart the evolution of the
orbital debris environment and review latest efforts to make space operations
more sustainable.
