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Center for Space Debris Data Collection, Processing and Analysis Keldysh Institute of Applied Mathematics (KIAM) Russian Academy of Sciences 4 Miusskaya Sq., Moscow, 125047 Russia
High Geocentric Orbit Space Debris Circular No.1 Efraim L. Akim KIAM Deputy Director
Coverage period ends on Jan 31, 2007 © Keldysh Institute of Applied Mathematics IntroductionThis circular opens new series of publications devoted to periodical summarizing of worldwide scientific activity in observations of space debris objects on high geocentric orbits (GEO, HEO and high near-circular non-GEO). Objects considered to be included into this publication are fragments (operational by nature, created in fragmentation events or in result of larger objects surface and construction deterioration due to environment conditions) having brightness fainter than 15th visual magnitude during most part of their observation time. This limit corresponds to equivalent approximately 1 m size object on geostationary orbit. It is possible that sometimes these objects can be brighter than 15th magnitude due to combination of their specific properties (surface reflectivity and attitude) and favorable observation conditions (good phase angle, high elevation etc.).
The goal of this publication is to give world scientific community imagination about the status of high geocentric orbit space debris researches and to provide most recent data for each discovered object including orbital parameters, estimated standard magnitude and estimated area-to-mass ratio value. Those data can be included into existed space debris models as well as can be used for study of long-term orbital evolution and possible origin of the objects. The Circular will also serve as some reference document for scientists and amateurs involved into those objects observations and data analysis. Operators of spacecrafts on high geocentric orbits (mainly in GEO) can use this publication in order to obtain more real description of situation around their orbital assets.
Observation planning, ephemeris support, processing and analysis of obtained data are made by researchers from Keldysh Institute of Applied Mathematics (KIAM) (Vladimir Agapov, Igor Molotov, Viktor Stepanyants, Vladimir Titenko) with invaluable help of Zakhariy Khutorovskiy (Vympel Corporation) and Vasiliy Yurasov (Scientific and Research Institute of Precise Instrument Engineering, IPIE).
All questions regarding cooperation in the joint research program for high geocentric orbit space debris studies should be sent to Prof. E. L. Akim, KIAM Deputy Director. All questions regarding observation schedule, required formats, ephemeris support, observations and orbital data processing, analysis and usage should be sent to Dr. V. M. Agapov. All questions regarding requirements for observation instruments, CCD-frames processing software, possible help in the instrument's upgrade in order to make possible participation in the research program should be sent to Dr. I. Ye. Molotov.
List of sensorsThis list includes all sensors participating to the date in a joint program of observation and analysis of space debris objects on high geocentric orbits. Each sensor has own identification number assigned to it in the KIAM space objects database. Most of sensors are involved into minor planet observations as well thus having the MPC assigned identification code. But for purposes of this research program it was decided to maintain separate ID system permitting to describe all participating sensors regardless of their other research programs involvement. Coordinates of sensors are given for reference purposes only and shouldn't be used in real observation processing. In the column "Instrument" common name, aperture (d, mm) and focal length (f, mm) of each instrument are given.
The list will be updated each time new sensor will send observations for studied objects.
Table 1. List of participating sensors
New objectsThis section contains information on objects newly detected during period Jan 1 - Jan 31, 2007.
There are two lists. The first one contains information on objects which had been successfully recovered in follow-up observations after initial detection and one-night tracking and for which orbital data and area-to-mass ratio value had been determined with high level of confidence. The second one contains information on objects having only one night track of observations. Complete set of orbital data can't be determined for these objects. Only some orbital parameters (mainly inclination and RAAN) are determined relatively accurate. The AMR values can't be determined for these objects at all.
It should be noted that all one-night tracks had been probed to identify with all other one-night tracks and with all known objects in the KIAM database having well determined orbits (both bright and faint). It is possible that identification had negative results not only due to absence of other tracks of the same object but also due to uncertainty caused by unknown AMR value which can result in very significant orbital evolution that prevents proper correlation of one-night tracks.
Each object listed in this section has two identifiers. The first one is assigned by the observer discovered the object and the second one is assigned in the KIAM space objects database. Since widely agreed space debris identification system doesn't exists still then all provided identifiers can be assumed as temporary ones. As soon as such the agreed system will appear, all objects will be assigned with the new identifiers.
Orbital elements are referring to True Equinox Mean Equator (TEME) coordinate system. Area-to-mass ratios are calculated assuming reflectivity coefficient equal to 1.3. Orbital elements for short tracks (Table 3) have obtained in two steps. At the first one attempt to construct orbit with fixed zero value eccentricity was made. In case of great (more than 3 expected sigma) residuals of measurements the second step was applied. At this step it was allowed eccentricity to vary as well.
Table 2. List of newly discovered and confirmed objects
Table 3. List of newly discovered objects having only single one-night track of observations
New identificationsThis section contains information on successful identification of newly and previously obtained single one-night tracks with each other as well as with objects having well determined orbits.
Table 4. New identifications
Updated orbitsThis section contains information on latest orbital updates for objects discovered prior to Jan 1, 2007 and observed at least once in Jan 2007.
Table 5. Updated orbital parameters for objects observed in Jan 2007
Master list of objectsThe master list of objects includes all high altitude orbit faint objects discovered to the date with description of obstacles of discovery and last update of orbital information. Due to large volume of the master list it will be distributing in electronic form only.
Observation statisticsThis section contains general statistics on obtained measurements.
Table 6. Distribution of measurements obtained by each facility by year of observation (as of Jan 31, 2007)
 19 ôåâðàëÿ 2007.
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