International Laser Ranging Service

1
International Laser Ranging Service

• GGOS Meeting
• GFZ
• Potsdam Germany
• March 1 and 2, 2005

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ILRS Organization
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(No Transcript)
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Data Applications

• Earth orientation parameters (polar motion and
  LOD)
• 3-D coordinates and velocities of the ILRS
  tracking stations
• Time-varying geocenter coordinates
• Static and time-varying coefficients of the
  Earth's gravity field
• Precision Orbit Determination
• Fundamental physical constants
• Lunar ephemerides and librations
• Lunar orientation parameters

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ILRS Analysis and Associate Analysis Centers

• ILRS SLR Official Combination Centers
• Prime ASI/CGS, Italian Space Agency/Space
  Geodesy Center, Italy
• Alternate DGFI, Deutsches Geodaetisches
  ForschungsInstitut, Germany
• Active Contributors to the SLR Combination
  Products
• ASI/CGS, Italian Space Agency/Space Geodesy
  Center "G. Colombo", Italy
• DGFI, Deutsches Geodaetisches ForschungsInstitut,
  Germany
• BKG, Bundesamt fuer Kartographi und Geodaesie,
  Germany
• GFZ, GeoForschungsZentrum, Germany
• JCET, Joint Center for Earth Systems Technology,
  USA
• NSGF, NERC Space Geodesy Facility, UK
• Lunar Analysis Centers
• FFI, Forsvarets ForskningsInstitut, Norway
• JPL, Jet Propulsion Laboratory, USA (SLR and
  Lunar)
• OCA, Observatoire de la Cote d'Azure, France
  (Lunar)
• POLAC, Paris Observatory Lunar Analysis Center,
  France (Lunar)
• University of Texas, Lunar Analysis Center
  (Lunar)

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Other SLR Analysis and Associate Analysis
Centers

• AIUB, Astronomical Institute of Berne,
  Switzerland
• CSR, Center for Space Research, U. of Texas
• DUT, Delft University of Technology, The
  Netherlands
• ESA/ESOC, European Space Agency/ESA Space
  Operations Center, Germany
• GAOUA, Main Astronomical Obser., National Academy
  of Sciences, Ukraine
• Geoscience Australia
• IAA, Institute of Applied Astronomy, Russia
• JAXA, Japan Aerospace Exploration Agency
• JPL, Jet Propulsion Laboratory, USA
• MCC, Mission Control Center, Russia
• Newcastle University, UK
• NICT, National Institute of Information and
  Communications Technology, Japan

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ILRS Customers

• IERS
• Supported Missions (POD)
• ILRS Analysis Centers
• Academic Research Centers
• National Agencies and Laboratories
• Commercial Organizations

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Current ILRS Missions Support
Gravity Probe-B Relativity ICESat Global
Topography (Ice, Oceans, and Land) GRACE-A/B
Static and Time Varying Gravity Field CHAMP
Gravity and Magnetic Field GFO-1 Ocean
Topography Envisat Ocean Topography,
Atmosphere ERS-2 Ocean Topography,
Atmosphere Jason Ocean Topography TOPEX/Posei
don Ocean Topography Larets
Technology, Gravity Field Starlette, Stella
Static and Time Varying Gravity Field, Tides
Meteor-3M Technology, SAGE Ajisai
Gravity Field LAGEOS- 1, 2 Ref. Frame,
Positioning, Static and T/V Gravity Beacon-C
Static and Time Varying Gravity Field
Etalon-1, 2 Positioning, EOP GLONASS-84,
87, 89 Orbit calibration and validation
GPS-35, 36 Orbit calibration and validation
Lunar Reflectors Apollo15, Apollo 11, Apollo
14, Luna 21, Luna 17 Key Passive
Satellites Active satellites with SLR
tracking only
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Upcoming Missions
Mission Application Launch CRYOSat Ice
budget July 2005 Galileo (2) Orbit
calibration and validation October
2005 ALOS Environmental remote sensing Late
2005 GOCE Gravity Field, Geoid, Ocean Surface
2006
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ILRS Station Operations

• Location of Stations
• Most stations are located close to participating
  agencies
• Some are located to enhance global distribution
  (South Africa, Tahiti, Arequipa)
• Voids in global distribution
• Satellite Priorities
• Priorities decrease with increasing orbital
  altitude and then increasing orbital inclination
• Priorities may be increased to intensify support
  for active missions (such as altimetry), special
  campaigns, and post-launch intensive tracking
• Priorities are reviewed and approved by the
  Governing Board
• See http//ilrs.gsfc.nasa.gov/satellite_missions/p
  riorities/index.html
• Scheduling, Coordination and Delivery of
  Observations
• Stations tracking schedules range from 1 to 4
  shifts per week
• Stations track according to priorities,
  predictions and their local capabilities
• The Governing Board approves special campaigns
• Special procedures (e.g. for vulnerable
  satellites) are approved by the Governing Board
  and managed by the Central Bureau
• Data is delivered in 1 -2 hours from acquisition

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Laser Ranging Data and Data Products

• Satellite Laser Ranging
• Data series spanning 3 decades at
  ftp//cddis.gsfc.nasa.gov/pub/slr/data)
• Operational Satellite Ephemerides/predictions at
  ftp//cddis.gsfc.nasa.gov/pub/slr/predicts)
• ILRS Station and EOP Combination Product (SINEX
  format)
• Station Coordinates 3 mm 2 mm/year
• EOP 0.2 milliarcsec LOD 60 microsec.
• Analysis Center contributions
• Station Coordinates
• Earth Origin
• Temporal and static gravity field (long
  wavelength)
• LAGEOS Orbits (10 mm/weekly)
• Position and EOP contributions available at
  ftp//cddis.gsfc.nasa.gov/pub/slr/products
• Lunar Laser Ranging
• Lunar Ephemerides 5 - 10 cm
• Lunar Libration .01 arcsec.
• Products available at http//ssd.jpl.nasa.gov/hori
  zons.html
• Measurement and product standards?
• Station Qualification Criteria ( data quantity,
  data quality, operational compliance)
• See http//ilrs.gsfc.nasa.gov/stations/site_info/
  global_report_cards/

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ILRS Future Activities

• Upgrades for improved performance (short term,
  long term)
• kilohertz ranging
• autonomous operation (24/7)
• improved event timers
• two-color ranging (refraction)
• better control systems for more efficient
  satellite pass interleaving
• more compact retroreflector arrays
• continuous data flow
• transponder operations (LLR and planetary
  ranging)
• broader applications (communications)
• Improved modeling (S/C center of mass,
  propagation, etc.)
• New Missions that will improve measurement
  quality
• Additional passive, high mass density satellites
  in new orbits
• Key Issues
• Deterioration of the network
• Non-performing stations
• Global distribution