Space Security Index

The Space Environment
is chapter assesses trends and developments related to the physical condition of the space
environment, with an emphasis on the impact of human activity in space — such as the
creation of space debris, the use of scarce space resources — such as the registration of orbital
slots and the allocation of radio frequencies, and the potential threat posed by Near Earth
Objects (NEOs).
Space debris, which predominantly consists of objects generated by human activity in space,
represents a growing and indiscriminate threat to all spacecraft. e impact of space debris
on space security is related to a number of key issues examined in this volume, including the
amount of space debris in various orbits, space surveillance capabilities that track space debris
to enable collision avoidance, as well as policy and technical eorts to reduce new debris and
to potentially remove existing space debris in the future.
While all space missions inevitably create some amount of space debris, mainly as rocket
booster stages are expended and released to drift in space along with bits of hardware, more
serious fragmentations are usually caused by energetic events such as explosions. ese can be
both unintentional, as in the case of unused fuel exploding, or intentional, as in the testing
of weapons in space that utilize kinetic energy interceptors. Catastrophic events of both
types have created thousands of long-lasting pieces of space debris. 1 e year 2010 broke the
trend of the preceding three years, in all of which there was a major debris-generating event.
In January 2007, the Chinese weather satellite FY-1C was destroyed with an Anti-Satellite
Weapon (ASAT) and in February 2009 two satellites — the Russian satellite Cosmos 2251
and the U.S. satellite Iridium 33 — collided for the rst time.
A growing awareness of the impact of space debris on the security of space assets has
encouraged space actors to take steps to mitigate the production of new debris through the
development and implementation of national and international debris mitigation guidelines,
also examined in this chapter.
Earth orbits are limited natural resources. Actors who wish to place a satellite in orbit
must secure an appropriate orbital slot in which to do so and secure a portion of the radio
spectrum to carry their satellite communications. Both radio frequencies and orbital slots are
indispensable tools for all space operations, and in certain orbits their national assignments
are coordinated through the International Telecommunication Union. is chapter assesses
the trends and developments related to the demand for orbital slots and radio frequencies, as
well as the conict and cooperation associated with the distribution and use of these scarce
space resources. is includes compliance with existing norms and procedures developed
through the ITU to manage the use and distribution of orbital slots and radio frequencies.
Space Security Impact
Space is a harsh environment and orbital debris represents a growing threat to the secure
access to, and use of, space due to the potential for collisions with spacecraft. Because of
orbital velocities of up to 7.8 km per second (~30,000 km per hour) in Low Earth Orbit
(LEO), debris as small as 10 cm in diameter carries the kinetic energy of a 35,000-kg
truck traveling at up to 190 km per hour. While objects have lower relative velocities in
Geostationary Earth Orbit (GEO), debris at this altitude is still moving as fast as a bullet
— about 1,800 km per hour. No satellite can be reliably protected against this kind of
destructive force and, while some satellites and spacecraft have been hardened to withstand
minor impacts from space debris, it is considered impractical to shield against objects bigger
than a few centimeters.
The Space Environment
CHAPTER ONE
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