• Title/Summary/Keyword: space science

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Performance Analysis of the First Korean Satellite Laser Ranging System

  • Choi, Man-Soo;Lim, Hyung-Chul;Choi, Eun-Jung;Park, Eunseo;Yu, Sung-Yeol;Bang, Seong-Cheol;Kim, Tae-Keun;Kim, Young-Rok;Kim, Dong-Jin;Seong, Kipyung;Ka, Neung-Hyun;Choi, Cer-Hee;Hwang, Joo-Yeon;Kucharski, Daniel;Han, In-Woo;Nah, Jakyoung;Jang, Jung-Guen;Jang, Bi-Ho;Lee, Sang-Jung
    • Journal of Astronomy and Space Sciences
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    • v.31 no.3
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    • pp.225-233
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    • 2014
  • 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 $25^{th}$ 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.).

OPTICAL SURVEY WITH KMTNET FOR DUSTY STAR-FORMING GALAXIES IN THE AKARI DEEP FIELD SOUTH

  • JEONG, WOONG-SEOB;KO, KYEONGYEON;KIM, MINJIN;KO, JONGWAN;KIM, SAM;PYO, JEONGHYUN;KIM, SEONG JIN;KIM, TAEHYUN;SEO, HYUN JONG;PARK, WON-KEE;PARK, SUNG-JOON;KIM, MIN GYU;KIM, DONG JIN;CHA, SANG-MOK;LEE, YONGSEOK;LEE, CHUNG-UK;KIM, SEUNG-LEE;MATSUURA, SHUJI;PEARSON, CHRIS;MATSUHARA, HIDEO
    • Journal of The Korean Astronomical Society
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    • v.49 no.5
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    • pp.225-232
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    • 2016
  • We present an optical imaging survey of AKARI Deep Field South (ADF-S) using the Korea Microlensing Telescope Network (KMTNet), to find optical counterparts of dusty star-forming galaxies. The ADF-S is a deep far-infrared imaging survey region with AKARI covering around 12 deg2, where the deep optical imaging data are not yet available. By utilizing the wide-field capability of the KMTNet telescopes (~4 deg2), we obtain optical images in B, R and I bands for three regions. The target depth of images in B, R and I bands is ~24 mag (AB) at 5σ, which enables us to detect most dusty star-forming galaxies discovered by AKARI in the ADF-S. Those optical datasets will be helpful to constrain optical spectral energy distributions as well as to identify rare types of dusty star-forming galaxies such as dust-obscured galaxy, sub-millimeter galaxy at high redshift.

A Study on the Strategies of the Positioning of a Satellite on Observed Images by the Astronomical Telescope and the Observation and Initial Orbit Determination of Unidentified Space Objects

  • Choi, Jin;Jo, Jung-Hyun;Choi, Young-Jun;Cho, Gi-In;Kim, Jae-Hyuk;Bae, Young-Ho;Yim, Hong-Suh;Moon, Hong-Kyu;Park, Jang-Hyun
    • Journal of Astronomy and Space Sciences
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    • v.28 no.4
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    • pp.333-344
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    • 2011
  • An optical tracking system has advantages for observing geostationary earth orbit (GEO) satellites relatively over other types of observation system. Regular surveying for unidentified space objects with the optical tracking system can be an early warning tool for the safety of five Korean active GEO satellites. Two strategies of positioning on the observed image of Communication, Ocean and Meteorological Satellite 1 are tested and compared. Photometric method has a half root mean square error against streak method. Also eccentricity method for initial orbit determination (IOD) is tested with simulation data and real observation data. Under 10 minutes observation time interval, eccentricity method shows relatively better IOD results than the other time interval. For follow-up observation of unidentified space objects, at least two consecutive observations are needed in 5 minutes to determine orbit for geosynchronous orbit space objects.