Comparison between the American and European approach towards Space Situation Awareness

2. Presentation Content
• Space Debris
– Earth to Space Threats
– Space to Space Threats
– Space to Earth Threats
• Space Situation Awareness – SSA
– The US Approach
– The European Approach
• A few observations

4. Space Debris ? Not my problem !
Definition: Space debris, also known as orbital debris, space junk,
and space waste, is the collection of objects in orbit around Earth
that were created by humans but no longer serve any useful
purpose. (Wikipedia)
 ‘Vast space, small satellites’ way of thinking
 ‘No disasters – Why bother ?’
 Out of more than 21,000 space elements larger than 10
cm tracked during 2011, only 3500 (~16%) were live
operating satellites.

5. From Earth to Space
Definition: Anti-satellite weapons (ASAT) are designed to
incapacitate or destroy satellites for strategic military purposes.
(Wikipedia)
 US and USSR experimented freely with ASAT weapons,
During the 60’s and 70’s
 On January 11th, 2007, China destroyed an old Chinese
orbiting weather satellite
 On February 21st, 2008, USA destroyed a
malfunctioning US spy satellite USA-193

6. SPACE to SPACE threats – Space collisions
 Events of close proximity occur numerous times each day.
A Passive scanning and tracking system (SOCRATES)
monitors the traffic
 Sorting to identify those that are high risk presents a
challenge.
 Planning an avoidance maneuver can also be challenging.

7. Kessler Syndrome (Donald J. Kessler)
 The density of objects in Earth orbit is high enough that
collisions between objects could cause a cascade – each
collision generating debris which increases the likelihood
of further collisions.
42% of all cataloged debris was the result of only 19
events

8. Accidents have happened before:
 On August 11th, 1993, the British Olympus-1 was hit
by ‘something’ and left adrift.
 On July 24th, 1996, the French microsatellite Cerise
(military use) was hit by fragments of an Ariane-1
launcher.
 On March 29th, 2006 the Russian Express-AM11
communications satellite span out of control due to
cooler leakage, high chances it was hit by debris

9. 10/02/2009 -16:56 UTC

10. Few things you should know…
 “The risk of collision per conjunction is one in 50 million
(1:50,000,000)”… John Campbell, executive vice
president of Iridium, June 2007
 This was not the top predicted close approach for that
report or even the top predicted close approach for any
of the Iridium satellites for the coming week !!

11. Recent events regarding space-space threats
 On October 28th, 2010. a 5.37 ton satellite named
EUTELSAT W3B suffered a major leak just after separation
from Arianne and later on was declared a total loss.
 On June 28th, 2011 an emergency evacuation of
the ISS was declared due to a dangerous Russian debris
that was discovered at the last minute and flew less than 250
meters from the ISS.
 On August 18th, 2011, a 5.7 ton satellite named EXPRESS
AM-4 was misplaced in orbit and now is considered a risk to
GPS and GEO satellites

12. Reentry: Space-to-Earth Threats
South Africa
Australia
Russia
US Saudi Arabia

13. Fallen trees and Space Debris
UK
Russia

14. Recent Reentry Events
• UARS – September 23rd, 2011 – Debris spread over the
Pacific ocean (5.9 ton – total, mass of ~530 kg hit earth)
• ROSAT – October 23rd, 2011 – Debris spread over the bay
of Bengal (2.6 ton – total, mass of ~1.7 ton hit earth)
• Phobos-Grunt – January 15th, 2012 – Debris spread over
the pacific ocean (13.5 ton – total, mass of debris yet
unknown)

16. Space Situation Awareness
• Definition: The requisite current and predictive knowledge
of the space environment and the operational environment
upon which space operations (Source: Definitions.net)
• The objective of the SSA is to support utilization of, and
access to, space through the provision of timely and
accurate information, data and services regarding the
space environment, and particularly regarding hazards to
infrastructure in orbit and on the ground (source: ESA).

17. SSA Operational Concepts – US Approach
The U.S. strategy to assure freedom
of access in space hinges on SSA:
the ability to find and track space
objects and determine their
capability and intent. (source: responsive
space situation awareness in 2020 – USAF)
OODA – Observe, Orient, Decide, Act

18. SSA Operational Concept – ESA approach
Unrestricted access to space and to space services is a common interest
of humankind. Accordingly, the need for sustainable space services and
possibly the need to take actions to guarantee the unrestricted use of
space are vital and recognized worldwide.

20. A Few Observations
• There are no laws regarding space debris (only gentlemen
agreements).
• Current passive warning systems HAVE NOT prevented
even one incident.
• Active measures must be taken NOW - even if we stop
all launches, the problem will only become worse.
• European approach regarding SSA is commercial, US
approach is strategic

21. Winds of change ??
• ASTRIUM VP for R&T Brigitte Serreault, publically announced
their interested in on-board protections against collisions at a
satellite level.
• The Swiss Space Center at the Swiss Federal Institute for
Technology in Lausanne, announced on February 15th its
plan to develop and launch a satellite to remove space debris
from low-Earth orbit. The $11-million (USD) satellite,
called Clean Space One