About us

59th International Astronautical Congress
logo
Glasgow, Scotland, 29 September - 3 October 2008

Analysis of the results of the 3 years observations of the GEO belt and the HEO objects by the ISON network

V.Agapov, I.Molotov, Z. Khutorovsky, V.Titenko

Keldysh Institute of Applied Mathematics
Russian Academy of Sciences


The ISON network
Beginning...

The International Scientific Optical Network (ISON) started with the single small instrument at Pulkovo Observatory and a few people involved in observations and data processing.

First trial observations of GEO May 2001

Initial tasks for the project:
  • support of radar experiments
  • obtaining data to confirm the theory of evolution of fragment clouds created in explosions of old GEO resident objects

... and Present

As of mid-2008, the ISON network joins:
  • 20 scientific institutions in 9 states, including partners from ESOC, AIUB, astronomical organizations of Bolivia, Georgia, Moldova, Russia, Tajikistan, Ukraine, Uzbekistan
  • 19 observatories and observation facilities
  • 24 optical instruments
  • more than 50 observers and researchers

Project principal coordinator responsible for the formulation of the tasks being solved, observation planning, collection and analysis of the results, space objects database maintenance is Keldysh Institute of Applied Mathematics of the Russian Academy of Sciences (KIAM RAS).

Current primary tasks:
  • regular GEO monitoring, discovery and tracking of new objects, maintaining GEO objects database as complete as possible
  • discovery and individual tracking of new objects on GTO and other HEO regimes, special HEO surveys will start soon

Current capabilities and research directions

As of mid-2008, the ISON is capable to perform:
  • Observation of selected objects across the whole GEO belt (360)
  • Near-GEO belt ( 2) surveys for the arc 130.3W 210.6E
  • GEO region wide surveys for the arc 30W 90E with the goal of discovery of all objects brighter than 16m
  • Uncatalogued GEO debris search (using different strategies, limiting magnitude 19m) and tracking (limiting magnitude 21m)
  • GTO and other HEO objects observations including faint space debris
  • Photometry of tracked objects
  • Study of physical properties of high altitude space debris
  • Measurements, orbits and object properties database maintenance
  • Analysis of close encounters
  • Improvement of the motion model used for data processing in the part of non-gravity perturbations

Main results obtained in 2005-2008

  • Since Jun 2007 wide GEO survey mode is implemented for longitudes 31.5W to 90E in a zone 16 with respect to the true GEO ring. Partial GEO survey mode is implemented for other longitudes
  • Overall number of measurements obtained exceeded 725000 (of which more than 360000 in 2008)
  • Number of continuously tracked objects in GEO and HEO - 1690, including 152 unknown bright GEO objects (brighter than 15m), which orbital data is published annually in ESOC Classification of Geosynchronous Objects (the last one Issue 10, Feb 2008), and 120 unknown bright HEO objects
  • 439 faint (fainter than 15m) GEO and GTO objects are discovered in GEO region surveys during the last 3 years, including objects with high AMR. Of this number, 192 GEO objects are tracked continuously.
  • Results are published monthly by KIAM in High Geocentric Orbit Space Debris Circular.
  • Unexpected changes in orbital motion of old GEO objects are revealed. The cause of these changes is not yet understood, but in any case they cannot be explained by natural forces like gravity or solar radiation pressure

Key achievements

Thanks to the ISON development and continuous improvement
  • Global GEO coverage capability is achieved. The only other observation system in the world having the same capability at present is the U.S. Space Surveillance Network operated by the U.S. Air Force
  • Population of known continuously tracked objects in the GEO region is increased by more than 35 percent
  • Presence of space debris clouds created in earlier suspected fragmentations of GEO objects is proved not only by statistical observation approaches but for the first time by long deterministic observations of individual members of the clouds
  • For the first time, a large amount of data on long time intervals is obtained for objects with high AMR. Both observational and orbital peculiarities of these objects are revealed and studied
  • Large amount of brightness measurements is obtained for nearly 1700 high altitude objects

Discovered new bright GEO objects characteristics

Discovered space debris measurement statistics

Discovered space debris population characteristics

Distribution of average brightness for 434 fragments

Distribution of average AMR value for 211 fragments

Distribution of inclination and RAAN for 432 fragments

Distribution of eccentricity and semimajor axis for 336 fragments

Distribution of perigee and apogee for 336 fragments

Orbital arcs (6-params orbit)

Orbit last update statistis

GEO and GEO-like object follow-up observation statistics

All known GEO objects population orbital characteristics

LEO and HEO experimental observation results obtained in 2007-2008

  • Successful experiments on independent discovery and tracking of debris created in fragmentations of Briz-M upper stage (object #28944), Block of ullage motor (#25054) and Fengyun 1C (#25730) are carried out. Small aperture (22 cm) optical instrument is used.
  • 120 earlier unknown bright and more than 150 faint objects are observed on HEO orbits (mostly GTO and Molniya-type). All discovered bright objects are continuously tracking at present.

HEO objects observation

Conclusions

  • Global GEO coverage capability is achieved
  • Population of known continuously tracked objects in the GEO region is increased by more than 35 percent. For the first time our knowledge of true GEO population of objects brighter than 15m is complete and presented for public
  • Several hundreds of previously unknown objects discovered in GEO region and on HEO orbits present clear indication of lack of our knowledge of true high orbits population
  • Presence of space debris clouds created in earlier suspected fragmentations of GEO objects is proved not only by statistical observation approaches but for the first time by long deterministic observations of individual members of the clouds
  • For the first time, a large amount of data on long time intervals is obtained for objects with high AMR. Both observational and orbital peculiarities of these objects are revealed and studied
  • The research should be expanded in order to obtain as complete information as possible on potentially dangerous objects crossing orbits of operational GEO and HEO spacecrafts
  • The ISON is an open scientific structure and all nations are welcome to participate

Acknowledgements

Authors thank Thomas Schildknecht and Reto Musci our great colleagues from the Astronomical Institute of the University of Bern for really scientific atmosphere developed in our cooperation.

We would like to thank Walter Flury, Heiner Klinkrad and Rudiger Jehn who boosted our cooperation with ESOC and ESA Tenerife space debris Observatory.

We address our special thanks to Richard Tremayne-Smith, James Dick and Phil Herridge for very fruitful cooperation in the beginning of the ISON.

We appreciate the work performing by the staff of the observatories in Zimmerwald, Tenerife/Teide, Nauchniy, Pulkovo, Mondy, Maidanak, Kitab, Ussuriysk, Terskol, Simeiz, Tiraspol, Tarija, Abastumani, Mayaki, Gissar, Milkovo, Yevpatoriya, Arkhyz and Andrushevka that participated earlier or continuing to participate in the ISON observation program.

Authors thank also Vladimir Kouprianov and Irina Guseva in Pulkovo observatory for the development of the CCD frame standard processing software and training support at the ISON observatories.

5 2008

About us


web counter