Proceedings of the 16th International Workshop on Laser Ranging 492 Status and Progress of ARGO J. Park, H. Lim, Y. Seo, J. Park, Y. Kim (1), Y. Son (2), Y. Kim (3) (1) Korea Astronomy and Space Science Institute (2) Korea Institute of Machinary and Materials (3) Kongju National University jupark@kasi.re.kr /Fax: +82-42-861-5610 Abstract Over the last few years, Korea Astronomy and Space Science Institute had prepared for introducing the SLR system in Korea. Even though we spent a lot of time to overcome the many barriers just same as other projects, we could finally start the ARGO project to make the series of SLR from this year. ARGO, new SLR systems of Korea, stands for the Accurate Ranging system for Geodetic Observation and this was the name of ship on which Jason and Argonauts voyaged to retrieve the Golden Fleece in Greek mythology. The goal of ARGO project is to make two SLR systems, one is a 40 centimeter mobile SLR system and another one is an 1 meter fixed SLR system, and to start the operation from the year 2011 and 2013 respectively. The participants of ARGO project are involved in five working groups related with the components of SLR system, for example Electro-Optics, to work more specifically. Due to their efforts including the visiting to several SLR sites in abroad, we could determined the more detailed requirements and scheduling for ARGO system. In this paper, we will give the current status and future plan of ARGO project with the context of requirements and scheduling of ARGO. Introduction ARGO means Korean SLR system and stands for ‗Accurate Ranging system for Geodetic Observation‘, which comes from the ship on which a great group of heroes boarded to find the Golden Fleece in the ancient Greek mythology. The final goal of ARGO program is to develop two SLR systems for 7 years from 2008 to 2014, one 40cm mobile system(ARGO- M) and one 1m fixed system(ARGO-F). The objectives of ARGO program can be categrorized into three items; i) space geodesy research and GEOSS/GGOS contribution by laser ranging for satellites with LRA, ii) precise obit determination(POD) through laser ranging measurement with mm level accuracy, iii) contribution to international SLR societies and ILRS network participation. ARGO will be developed with the cooperation of foreign institutes and under supports of international advisory committee and domestic advisory committee which consist of ten experts, respectively. As shown in Figure 1, ARGO-M will be completed by 2011 and then ARGO-F by 2014. Two Korean satellites with LRA, STSAT- 2 and KOMPSAT-5 will be launched in 2009 and 2010, respectively. So, ARGO-M and ARGO-F will be used for laser tracking of these two Korean satellites. System requirements of ARGO-M was generated by five working groups in September 2008, optics subsystem, opto-electronics subsystem, laser subsystem, tracking mount subsystem and ARGO operation system. Until now, system configuration and conceptual design of ARGO-M were made and its detailed specifications were also generated. Major characteristics of ARGO-M are following: