Jang-Hyun Park (Korea Astronomy and Space Science Institute), Young-Jun Choi (Korea Astronomy and Space Science Institute), Hong-Kyu Moon (Korea Astronomy and Space Science Institute), Hong-Suh Yim (Korea Astronomy and Space Science Institute), Young-Ho Bae (Korea Astronomy and Space Science Institute), Jong-Uk Park (Korea Astronomy and Space Science Institute)
Keywords: SSA
Abstract:
We are going to present a brief introduction to the OWL (Optical Wide-field patroL) network, one of Korean space situational awareness facilities. Primary objectives of the OWL network are 1) to obtain orbital information of Korean domestic LEOs using optical method, 2) to monitor GEO-belt over territory of Korea, and 3) to alleviate collisional risks posed to Korean satellites from space debris. For these purposes, we are planning to build a global network of telescopes which consists of five small wide-field telescopes and one 2m class telescope. The network of small telescopes will be dedicated mainly to the observation of domestic LEOs, but many slots will be open to other scientific programs such as GRB follow-up observations. Main targets of 2m telescope not only include artificial objects such as GEO debris and LEO debris with low inclination and high eccentricity, but also natural objects such as near Earth asteroids. We expect to monitor space objects down to 10cm in size in GEO using the 2m telescope system. Main research topics include size distribution and evolution of space debris. We also expect to utilize this facility for physical characterization and population study of near Earth asteroids. The aperture size of the small telescope system is 0.5m with Rechey-Cretian configuration and its field of view is 1.75 deg x 1.75 deg. It is equipped with 4K CCD with 9um pixel size, and its plate scale is 1.3 arcsec/pixel. A chopper wheel is employed to maximize astrometric solutions in a single CCD frame, and a de-rotator is used to compensate field rotation of the alt-az type mount. We have designed a compact end unit in which three rotating parts (chopper wheel, filter wheel, de-rotator) and a CCD camera are integrated, and dedicated telescope/site control boards for the OWL network. The design of 2m class telescope is still under discussion yet is expected to be fixed in the first half of 2013 at the latest. The OWL network will be operated in a fully autonomous mode based on scheduled observation. We have designed a compact and robust system for fully robotic operation. The network operating system located in the headquarter issues command files for observation which are transferred to each local site. After that, the site operating system interprets command files and controls each telescope system. In this way, we obtain and update orbital information of domestic satellites based on purely optical method. A prototype of the network telescope system will be installed at a test bed in Korea in commissioning phase. After the test operation, the design of the network telescope system will be finalized in the end of 2012. The installation of the telescope systems in 3 local sites will be completed in 2013, and the so-called “OWL basic network”” will start normal operations. In the first two years of the second stage of the OWL Project (2014-2015), we plan to place two small wide-field telescopes, and we build the 2m telescope system to complete the OWL network in the 2016.
Date of Conference: September 11-14, 2012
Track: Poster