Advanced Maui Optical and Space Surveillance Technologies Conference
Maui, Hawaii, September 1-4, 2009
Faint High Orbit Debris Observations with ISON Optical Network
Igor Molotov, Vladimir Agapov and ISON team
ISON
International scientific optical network civilian non-government project devoted to space debris research and space situation awareness.
Legend:
Green circles – ISON observatory working in the project during a few years already
Blue circles – ISON observatories working first year only
Yellow circles – ISON observatories where preparatory work are carried out
Orange circles – observatories – Russian partners of the ISON
Red circles – observatories – foreign partners of the ISON
ISON structure
- network of optical facilities:
- search and survey subsystem for studying of bright (not fainter than 15.5m) objects in GEO region (preliminary operations)
- subsystem for high orbit faint (fainter than 15.5m) space debris detection and tracking (operational)
- search and survey subsystem for studying of bright (not fainter than 13-14m) objects on HEO, MEO and LEO orbits (in development)
- network operation supporting groups:
- electric and software engineering
- optical and mount engineering
- observation planning and data processing group
- center for data accumulation, analysis and orbital archive maintenance
20 new telescopes and 35 GPS-based timing devices are produced, 30 CCD cameras are purchased, standard software for CCD frames reduction and telescope equipment control is elaborated
Search and survey subsystem for studying of bright GEO-objects consists of 11 telescopes of 22-cm aperture with FOV of 4° and 5.5°
Subsystem for high orbit faint space debris detection and tracking consist of telescopes of 0.4-2.6 m apertures
Search and survey subsystem for studying of bright HEO and LEO objects will consists of 4 telescopes of 12.5-cm aperture with FOV of 15° and 10 telescopes of 25-cm - with FOV of 3°
2nd meeting of ISON team Jan. 2007 Zvenigorod
Goals of the ISON faint fragment observations
- estimation of real population of artificial objects on high geocentric orbit
- determining of possible origin of the discovered objects
- verification of the space debris distribution and evolution models for high orbits
- estimation of the level of danger caused by space debris fragments for operational spacecrafts on high orbits at present and in the future
Beginning of ISON observations of faint GEO fragments:
- First experiments with 64 cm telescope AT-64 in Nauchny in October 2004:
- adjusting of a method of the fragments discovering
- checking theory on orbital evolution of the GEO object explosion fragments
- AT-64 and ZTSh telescopes in Nauchny, and Zeiss-1000 in Tenerife search fragments in selected search fields Zimmerwald, Nauchny, Maidanak, Mondy, Arkhyz and Mayaki observatories provide the follow up tracking
- 160 unknown objects of 15-20.5m are detected during 2005-2006
- 32000 measurements in 2150 tracks are obtained
The fields for fragment search were chosen at the points where the apparent density of catalogued GEO objects in the right ascension - declination space is higher, or where trajectories of fragments of presumably exploded objects are crossing (yellow lines – Ekrans, magenta lines – Transtages).
New strategy of ISON faint fragment observations
ZTSh and AT-64 stopped the searching of new uncatalogued fragments and concentrated on reacquisition and tracking of the fragments that were discovered earlier.
New method of fragment discovering and follow up tracking is in adjusting using the survey telescopes of small aperture but large FOV.
It is elaborated a few survey modes and algorithm permitting to find correlation between uncorrelated short tracks in order to discover new objects and to establish their orbits.
Involvement of new telescopes into surveys and follow up tracking of faint space debris fragments
Statistics of ISON output for faint fragments from 2004 to 2009
Distribution of discovered 556 fragments by telescopes
(341 objects / 215 uncorrelated tracks)
Distribution of obtained faint fragment tracks by telescope during 2009
Distribution of average brightness for 546 fragments
(including 341 object and 205 uncorrelated one-night tracks)
Distribution of average AMR value for 306 fragments
Distribution of apogee and perigee for 439 fragments
(including 341 object and 98 uncorrelated one-night tracks)
Distribution of eccentricity and semi-major axis for 439 fragments
(including 341 object and 98 uncorrelated one-night tracks)
Distribution of RAAN and Inclination for 544 fragments
(including 341 object and 203 uncorrelated one-night tracks)
CONCLUSION
Dedicated ISON subsystem for observations of faint fragments at high orbits is formed and includes now 14 telescopes with aperture from 0.4 to 2.6 m.
Small 22 cm telescopes with large FOV (especially PH-1 in Nauchny) provide addition contribution into fragment discovery rate thanks to high variability of fragment brightness.
Regular process of discovering and tracking of many high orbit fragments is established (to the date almost 300,000 measurements in 16,000 tracks are obtained for 556 fragments).
200 faint fragments are tracked practically continuously, 30 of them are already tracked during three years and 6 – more than four years.
For the first time, a large amount of data on long time intervals is obtained for objects with high AMR. It was found that many of the faint GEO objects have not only the unusual AMR value, but also a strange magnitude pattern.
Presence of space debris clouds created in earlier suspected fragmentations of GEO objects is for proved by long deterministic observations of individual members of the clouds.
The ISON research team participated in the special IADC campaign on studying the physical properties of high AMR value objects.
It is expected that faint fragment discovery statistics will be significantly improved since 2010 thanks to involvement of new telescopes and adjusting of the survey observation mode.
Level of the faint GEO fragment research has increased significantly
Размещено 17 сентября 2009
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