Orbit Determination Using SLR Data for STSAT-2C: Short-arc Analysis

김영록,박은서,Daniel Kucharski1,임형철 한국우주과학회 2015 Journal of Astronomy and Space Sciences Vol.32 No.3

In this study, we present the results of orbit determination (OD) using satellite laser ranging (SLR) data for the Science and Technology Satellite (STSAT)-2C by a short-arc analysis. For SLR data processing, the NASA/GSFC GEODYN II software with one year (2013/04 – 2014/04) of normal point observations is used. As there is only an extremely small quantity of SLR observations of STSAT-2C and they are sparsely distribution, the selection of the arc length and the estimation intervals for the atmospheric drag coefficients and the empirical acceleration parameters was made on an arc-to-arc basis. For orbit quality assessment, the post-fit residuals of each short-arc and orbit overlaps of arcs are investigated. The OD results show that the weighted root mean square post-fit residuals of short-arcs are less than 1 cm, and the average 1-day orbit overlaps are superior to 50/600/900 m for the radial/cross-track/along-track components. These results demonstrate that OD for STSAT-2C was successfully achieved with cm-level range precision. However its orbit quality did not reach the same level due to the availability of few and sparse measurement conditions. From a mission analysis viewpoint, obtaining the results of OD for STSAT-2C is significant for generating enhanced orbit predictions for more frequent tracking.

Attitude and Spin Period of Space Debris Envisat Measured by Satellite Laser Ranging

Kucharski, Daniel,Kirchner, Georg,Koidl, Franz,Cunbo Fan,Carman, Randall,Moore, Christopher,Dmytrotsa, Andriy,Ploner, Martin,Bianco, Giuseppe,Medvedskij, Mikhailo,Makeyev, Andriy,Appleby, Graham,Suzuk IEEE 2014 IEEE transactions on geoscience and remote sensing Vol.52 No.12

<P>The Environmental Satellite (Envisat) mission was finished on April 8, 2012, and since that time, the attitude of the satellite has undergone significant changes. During the International Laser Ranging Service campaign, the Satellite Laser Ranging (SLR) stations have performed the range measurements to the satellite that allowed determination of the attitude and the spin period of Envisat during seven months of 2013. The spin axis of the satellite is stable within the radial coordinate system (RCS; fixed with the orbit) and is pointing in the direction opposite to the normal vector of the orbital plane in such a way that the spin axis makes an angle of 61.86° with the nadir vector and 90.69° with the along-track vector. The offset between the symmetry axis of the retroreflector panel and the spin axis of the satellite is 2.52 m and causes the meter-scale oscillations of the range measurements between the ground SLR system and the satellite during a pass. Envisat rotates in the counterclockwise (CCW) direction, with an inertial period of 134.74 s (September 25, 2013), and the spin period increases by 36.7 ms/day.</P>

A method to calculate zero-signature satellite laser ranging normal points for millimeter geodesy - a case study with Ajisai

Kucharski, Daniel,Kirchner, Georg,Otsubo, Toshimichi,Koidl, Franz TERRA SCIENTIFIC PUBLISHING COMPANY 2015 EARTH PLANETS AND SPACE Vol.67 No.1

Spin Axis Precession of LARES Measured by Satellite Laser Ranging

Kucharski, Daniel,Hyung-Chul Lim,Kirchner, Georg,Otsubo, Toshimichi,Bianco, Giuseppe,Joo-Yeon Hwang IEEE 2014 IEEE geoscience and remote sensing letters Vol.11 No.3

<P>Satellite laser ranging (SLR) is an efficient technique to measure spin parameters of the fully passive satellite LARES. Analysis of the laser range measurements gives information about the spin rate of the spacecraft and the orientation of its spin axis. A frequency analysis applied to the SLR data indicates an exponential increase of the satellite's spin period: T = 11.7612 ·exp(0.00293327 ·D) , RMS = 0.115 s, where D is in days since launch. The initial spin period of LARES is calculated from the spin observations during the first 30 days after launch and is equal to T<SUB>0</SUB> = 11.7131, RMS = 0.073 s. The spin axis of the satellite is precessing around the initial coordinates of right ascension RA<SUB>initial</SUB> = 186.5<SUP>°</SUP>, RMS<SUB>RA</SUB> = 3.1<SUP>°</SUP>, and Declination Decinitial = - 73.0<SUP>°</SUP>, RMS<SUB>Dec</SUB> = 0.7<SUP>°</SUP> (J2000 inertial reference frame), with a period of 211.7 days. The precession of the spin axis may be responsible for the observed oscillation of the slowing down rate: the spin half-life period (the time after which the spin period has doubled) varies between 209 and 267 days. The measured spin parameters of LARES are compared-and show good agreement-with the theoretical predictions given by the satellite spin model. Information about the spin parameters of LARES is necessary for the accurate modeling of the forces and torques that are affecting the orbital motion of the satellite.</P>

Orbit Determination Using SLR Data for STSAT-2C: Short-arc Analysis

Young-Rok Kim,Eunseo Park,Daniel Kucharski,Hyung-Chul Lim 한국우주과학회 2015 Journal of Astronomy and Space Sciences Vol.32 No.3

In this study, we present the results of orbit determination (OD) using satellite laser ranging (SLR) data for the Science and Technology Satellite (STSAT)-2C by a short-arc analysis. For SLR data processing, the NASA/GSFC GEODYN II software with one year (2013/04 – 2014/04) of normal point observations is used. As there is only an extremely small quantity of SLR observations of STSAT-2C and they are sparsely distribution, the selection of the arc length and the estimation intervals for the atmospheric drag coefficients and the empirical acceleration parameters was made on an arc-to-arc basis. For orbit quality assessment, the post-fit residuals of each short-arc and orbit overlaps of arcs are investigated. The OD results show that the weighted root mean square post-fit residuals of short-arcs are less than 1 cm, and the average 1-day orbit overlaps are superior to 50/600/900 m for the radial/cross-track/along-track components. These results demonstrate that OD for STSAT-2C was successfully achieved with cm-level range precision. However its orbit quality did not reach the same level due to the availability of few and sparse measurement conditions. From a mission analysis viewpoint, obtaining the results of OD for STSAT-2C is significant for generating enhanced orbit predictions for more frequent tracking.

Orbit Determination Using SLR Data for STSAT-2C: Short-arc Analysis

Kim, Young-Rok,Park, Eunseo,Kucharski, Daniel,Lim, Hyung-Chul The Korean Space Science Society 2015 Journal of Astronomy and Space Sciences Vol.32 No.3

In this study, we present the results of orbit determination (OD) using satellite laser ranging (SLR) data for the Science and Technology Satellite (STSAT)-2C by a short-arc analysis. For SLR data processing, the NASA/GSFC GEODYN II software with one year (2013/04 - 2014/04) of normal point observations is used. As there is only an extremely small quantity of SLR observations of STSAT-2C and they are sparsely distribution, the selection of the arc length and the estimation intervals for the atmospheric drag coefficients and the empirical acceleration parameters was made on an arc-to-arc basis. For orbit quality assessment, the post-fit residuals of each short-arc and orbit overlaps of arcs are investigated. The OD results show that the weighted root mean square post-fit residuals of short-arcs are less than 1 cm, and the average 1-day orbit overlaps are superior to 50/600/900 m for the radial/cross-track/along-track components. These results demonstrate that OD for STSAT-2C was successfully achieved with cm-level range precision. However its orbit quality did not reach the same level due to the availability of few and sparse measurement conditions. From a mission analysis viewpoint, obtaining the results of OD for STSAT-2C is significant for generating enhanced orbit predictions for more frequent tracking.

Spin Axis Determination of Defunct GLONASS Satellites Using Photometry Observation

Lee, Jeeho,Park, Eunseo,Choi, Man-Soo,Kucharski, Daniel,Yi, Yu,Park, Jong-Uk The Korean Space Science Society 2021 Journal of astronomy and space sciences Vol.38 No.1

GLONASS, a satellite navigation system developed in Russia since 1976, is defunct and orbits in an unstable attitude. The satellites in these problems are not managed and there is no precise information, which can increase the risk of collisions with other space objects. In this study, detailed attitude dynamic have to be analyzed through photometry data, which requires spin period and spin axis. The light curve data is obtained by observing through the photometer at the Graz station and the power spectrum is calculated to obtain the cycle of the satellite. The geometric relationship between observer and sun is analyzed for GLONASS-50 satellite. The box-wing model is applied to obtain the phase reflection of the satellite and obtain the Irradiation of the satellite through this information. In Light Curve and Irradiation, the spin axis is calculated for each peak points with the distance square minimum technique. The spin axis of the GLONASS-50 satellite is RA = 116°, Dec = 92°.

Spin Axis Determination of Defunct GLONASS Satellites Using Photometry Observation

Jeeho Lee,Eunseo Park,Man-Soo Choi,Daniel Kucharski,Yu Yi,Jong-Uk Park 한국우주과학회 2021 Journal of Astronomy and Space Sciences Vol.38 No.1

GLONASS, a satellite navigation system developed in Russia since 1976, is defunct and orbits in an unstable attitude. The satellites in these problems are not managed and there is no precise information, which can increase the risk of collisions with other space objects. In this study, detailed attitude dynamic have to be analyzed through photometry data, which requires spin period and spin axis. The light curve data is obtained by observing through the photometer at the Graz station and the power spectrum is calculated to obtain the cycle of the satellite. The geometric relationship between observer and sun is analyzed for GLONASS-50 satellite. The box-wing model is applied to obtain the phase reflection of the satellite and obtain the Irradiation of the satellite through this information. In Light Curve and Irradiation, the spin axis is calculated for each peak points with the distance square minimum technique. The spin axis of the GLONASS-50 satellite is RA = 116°, Dec = 92°.

Performance Analysis of the First Korean Satellite Laser Ranging System

Man-Soo Choi,Hyung-Chul Lim,Eun-Jung Choi,Eunseo Park,Sung-Yeol Yu,Seong-Cheol Bang,Tae-Keun Kim,Young-Rok Kim,Dong-Jin Kim,Kipyung Seong,Neung-Hyun Ka,Cer-Hee Choi,Joo-Yeon Hwang,Daniel Kucharski,In- 한국우주과학회 2014 Journal of Astronomy and Space Sciences Vol.31 No.3

The first Korean satellite laser ranging (SLR) system, Daedeok SLR station (DAEK station) was developed by Korea Astronomy and Space Science Institute (KASI) in 2012, whose main objectives are space geodesy researches. In consequence, Korea became the 25th country that operates SLR system supplementing the international laser tracking network. The DAEK station is designed to be capable of 2 kHz laser ranging with precision of a few mm both in daytime and nighttime observation of satellites with laser retro-reflector array (LRA) up to the altitude of 25,000 km. In this study, characteristics and specifications of DAEK station are investigated and its data quality is evaluated and compared with International Laser Ranging Service (ILRS) stations in terms of single-shot ranging precision. The analysis results demonstrated that the DAEK station shows good ranging performance to a few mm precision. Currently, the DAEK station is under normal operations at KASI headquarters, however, it will be moved to Sejong city in 2014 to function as a fundamental station for space geodesy researches in combination with other space geodesy systems (GNSS, VLBI, DORIS, etc.).