National Aeronautics and Space Administration

USA Space Debris Environment and

Operational Updates

Presentation to the 47th Session of the

Scientific and Technical Subcommittee

Committee on the Peaceful Uses of Outer Space

United Nations

8-19 February 2010

National Aeronautics and Space Administration

Presentation Outline

• Evolution of Low Earth Orbit Satellite Population

• Space missions in 2009

• Collision Avoidance Maneuvers

2

• GEO Population and Retirement of USA GEO Spacecraft in 2009

• Satellite Fragmentations in 2009

• Inspection of Hubble Space Telescope

• First International Conference on Orbital Debris Removal

National Aeronautics and Space Administration

8000

9000

10000

11000

12000

Number of C

ataloged Objects

Total Objects

Fragmentation Debris

Spacecraft

Mission-related Debris

Rocket Bodies

Growth of the Cataloged Satellite Population in

Low Earth Orbit: Numbers of Objects

• The number of cataloged objects in low Earth orbit has increased 62% since

1 January 2007.

Iridium 33 and Cosmos 2251 Collision

Destruction of Fengyun-1C

3

0

1000

2000

3000

4000

5000

6000

7000

8000

1956

1958

1960

1962

1964

1966

1968

1970

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

2010

Number of C

ataloged Objects

Rocket Bodies

National Aeronautics and Space Administration

Growth of the Cataloged Satellite Population in

Low Earth Orbit: Mass of Objects

• Recently, the rate of mass growth in low Earth orbit has averaged 50 metric

tons per year. (data below does not include ISS components)

2.0

2.5

Mass in Orbit (millions of kg)

Total Objects

Spacecraft

Rocket Bodies

Fragmentation Debris

Mission-related Debris

4

0.0

0.5

1.0

1.5

1957

1959

1961

1963

1965

1967

1969

1971

1973

1975

1977

1979

1981

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

2009

Mass in Orbit (millions of kg)

Mir De-orbit

National Aeronautics and Space Administration

NASA Space Missions of 2009

• Twelve NASA space missions were undertaken in 2009.Mission Launch Date Destination Other Objects Left in Earth Orbit

NOAA 19 * 06 February LEOOne rocket body left in disposal orbit; reentered after

2.5 months

Kepler 07 March Heliocentric OrbitOne rocket body left in disposal orbit between LEO

and GEO

STS-119 15 March LEO (ISS) No objects left in Earth orbit

STS-125 11 May LEO (HST) No objects left in Earth orbit

PHARMASAT 19 May LEOOther objects assoicated with this flight are not

NASA-related, but all will have short orbital lifetimes.

Lunar Reconnaissance Orbiter 18 June Lunar orbit No objects left in Earth orbit

5

• All spacecraft, rocket bodies, and mission-related debris residing in or passing through LEO have already reentered or will reenter within 25 years.

Lunar Reconnaissance Orbiter 18 June Lunar orbit No objects left in Earth orbit

LCROSS 18 June Lunar impact No objects left in Earth orbit

GOES 14 * 27 June GEOOne rocket body left in disposal orbit between LEO

and GEO

STS-127 15 July LEO (ISS)Three small payloads and three small debris left in

low altitude, short-lived orbits

STS-128 29 August LEO (ISS) No objects left in Earth orbit

STS-129 16 November LEO (ISS) No objects left in Earth orbit

WISE 14 December LEO

One rocket body left in disposal orbit between LEO

and GEO; one mission-related debris left in short-

lived orbit

* Spacecraft developed and launched by NASA for NOAA

National Aeronautics and Space Administration

Orbital Debris Collision Avoidance

• Since 2007 NASA has required all of its maneuverable spacecraft in LEO or

GEO to conduct satellite conjunction assessments on a routine basis to

avoid accidental collisions with resident space objects.

• During 2009 NASA conducted eight collision avoidance maneuvers and

assisted France with a collision avoidance maneuver involving the PARASOL

spacecraft.Spacecraft Maneuver Date Object Avoided

6

* Operating in NASA-led Earth observation network

Spacecraft Maneuver Date Object Avoided

TDRS 3 27 Janaury Proton rocket body

ISS 22 March CZ-4 rocket body debris

Cloudsat 23 April Cosmos 2251 debris

EO-1 11 May Zenit rocket body debris

ISS 17 July Proton rocket body debris

Space Shuttle 10 September ISS debris

PARASOL (France)* 29 September Fengyun-1C debris

Aqua 25 November Fengyun-1C debris

Landsat 7 11 December Formosat 3D

National Aeronautics and Space Administration

GEO Population Assessment

• For many years NASA has been observing the GEO uncataloged debris

population. Data suggest that the population of debris between 10 cm and

1 m is at least twice that of the cataloged population.

2,500

3,000

3,500

Cumulative Number of objects nea

r GEO

of a given

size an

d larger

7

0

500

1,000

1,500

2,000

2,500

0.1 1 10

Cumulative Number of objects nea

r GEO

of a given

size an

d larger

Size of object (meters)

National Aeronautics and Space Administration

Disposal of USA GEO Satellites in 2009

• Eight USA civil GEO spacecraft conducted disposal maneuvers in 2009.

Spacecraft International Designator Minimum Height above GEO Maximum Height above GEO

SBS 6 1990-091A 335 395

INTELSAT 605 1991-055A 250 290

DIRECTV 1 1993-078A 340 390

INTELSAT 704 1995-001A 305 315

DIRECTV 3 1995-029A 340 380

8

• TDRS 1 also completed its mission in 2009 and will be placed in a compliant

disposal orbit in 2010.

All spacecraft except Galaxy 4R meet USA, IADC, and United Nations recommendations for

GEO disposal and will not come within the GEO protected region during the next 200 years.

DIRECTV 3 1995-029A 340 380

GOES 10 1997-019A 335 355

ECHOSTAR 5 1999-050A 420 450

GALAXY 4R * 2000-020A 120 130

* This spacecraft suffered primary and secondary propulsion system failures prior to 2004.

National Aeronautics and Space Administration

Satellite Fragmentations in 2009

• Iridium 33 and Cosmos 2251 Collision:

Accidental collision on 10 February produced more than 2000 trackable

debris. (update on next chart)

• Proton launch vehicle ullage motor:

9

Ullage motor from Cosmos 2139-2141 mission (1991-025) broke-up on 8

March. To date, 32 debris have been cataloged by the USA Space

Surveillance Network; half have already reentered.

• Cosmos 192:

This 42-year old spacecraft (1967-116) experienced a minor fragmentation

on 30 August. Less than 20 confirmed debris; only three debris officially

cataloged due to high drag coefficients, and all three had reentered within

two months.

National Aeronautics and Space Administration

Update on Iridium-Cosmos Collision

• One year after the accidental collision of Iridium 33 and Cosmos 2251, more

than 2000 large debris had been identified.

1200

1400

1600

1800

Apogee

Perigee

(kilometers)

10

0

200

400

600

800

1000

85 90 95 100 105 110 115

Orbital Period (minutes)

Altitude(kilometers)

Cosmos 2251 Debris

Iridium 33 Debris

National Aeronautics and Space Administration

Inspection of the Hubble Space Telescope

• In May 2009, Space Shuttle Atlantis

visited and successfully

refurbished the Hubble Space

Telescope.

• The Wide Field Planetary Camera 2

was removed and returned to Earth

after 16 years in space.

11

after 16 years in space.

• Numerous large impact features

(green circles) had occurred since

the last servicing mission in 2002

(red circles).

• Microscopic examinations have

revealed nearly 700 hypervelocity

impact features greater than 0.3

mm in diameter.WFPC2 Radiator (2.2 m long, 0.8 m tall)

National Aeronautics and Space Administration

Inspection Instruments

• Keyence VHX-600 digital microscope (up to 5000x optical, 2D and 3D)

– Records each impact feature’s shape, size, depth, and volume

• LAP CAD-Pro laser template projector

12

National Aeronautics and Space Administration

Measuring Large Craters

Four Diameters:

– Spallation

– Bare metal

– “Burned” metal

– Lips or center

Inputs

13

Two Depths:

– Central crater depth

– Paint thickness

Results

National Aeronautics and Space Administration

Measuring Small Craters

Two Diameters:

– Spallation

– Center

Inputs

14

One Depth:

– Central crater depth

Results

National Aeronautics and Space Administration

First International Conference on

Orbital Debris Removal

• NASA and the US Defense Advanced

Research Projects Agency (DARPA)

last year co-hosted the first

international conference dedicated to

the subject of the removal of debris

from Earth orbit.

• The conference was held in the vicinity

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• The conference was held in the vicinity

of Washington, DC, and was attended

by more than 275 persons from nine

countries.

• More than 50 presentations examined

the technical, economic, legal, and

policy issues associated with removing

small and large debris in low and high

altitude orbits.

International Conference on

Orbital Debris RemovalDecember 8-10, 2009