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

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.

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

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.

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

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

10/02/2009 -16:56 UTC

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 !!

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

Reentry: Space-to-Earth Threats

Australia

South Africa

Russia

US Saudi Arabia

Fallen trees and Space Debris

Russia

UK

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)

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).

SSA Operational Concepts – US Approach

OODA – Observe, Orient, Decide, Act

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)

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.

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

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