Jaedong Seong, Korea Aerospace Research Institute (KARI); Okchul Jung, Korea Aerospace Research Institute (KARI); Dae Won Chung, Korea Aerospace Research Institute (KARI)
Keywords: KARI, Space Debris, Space Situational Awareness, Space Traffic Management
Abstract:
KARI is the national space development organization of South Korea and it has a role in secure operation of space assets. Since Chinese ASAT, KARI has been including SSA activities as a major part of satellite operation and so far, KARI has been working to expand SSA and STM activities in various fields. These activities can be categorized into six items: Mitigation, Measurement, Protection, Disposal, Remediation and International Cooperation.
First item is mitigation. Currently, KARI is operating conjunction assessment tool all the time. It can download the TLE and CDM data from CSpOC automatically and performs conjunction assessments. If there is specific risky event, it sends e-mail and mobile message to inform operators. In fine assessment, KARI CA tool can send precise orbit or maneuver information to CSpOC and it also can generate optimized collision avoidance maneuver. Meanwhile, if the risk object is operational object, we can contact the owner or operator of secondary object and directly exchange relevant infornation to minimize collision risk. KARI have been collaborated with other space agencies in SSA & STM area so far.
Second item is about measurement. Generally, radar measurement is useful for LEO objects and other agencies are now operating radar sensor for SSA & STM. Actually, KARI dont have the radar sensor so far, but we have been performed related research to prepare the design and operation of radar sensor. KARI have radar facility located in Jeju island of Korea for tracking of Korean launch vehicles. KARI performed an experiment for tracking space objects having large RCS. Now we are trying to research on increase of maximum tracking range of the Radar in Jeju island. The related research includes ISAR image measuring test with Fraunhofer TIRA radar and the development of space object surveillance sensor simulator.
Third item is about protection. There are several upcoming space programs and among them, KOMPSAT-6 and KOMPSAT-7 started to consider the space object environment in their mission orbit. We determine whether space mission can satisfy the international guidelines using NASA and ESA space environment models and tools. And if the proposed space mission cant satisfy the international guidelines, such as NASA safety standard, we reconsider to design process and enhance the vulnerability. For example, additional shielding parts installed to protect critical parts from hypervelocity objects.
Fourthly, removal and disposal are also important activity. Now lots of space agencies are trying to comply with removal or disposal guidelines and 25 years rule is representative international guidelines. KOMPSAT-2 is LEO satellite and it can be first candidate for post mission disposal because its operation was officially terminated at 2015 but now it represents good health conditions, such as fuel and battery. We performed the research about post mission disposal plan with given satellite resources and operational constraints. And we tried to find the optimum plan that minimizes remain orbital lifetime even if international guidelines are already satisfied. Furthermore, additional reentry analysis, such as survivability and impact location analysis, also performed.
Fifth item is remediation. To remove large space object, KARI is performing research about active debris removal technologies. Five degree of freedom ground-based test bed has been developed to demonstrate proximity operation algorithms and now small satellite, which is about six-unit cube satellite, is being developed. Furthermore, on-orbit test is also planned using target and chaser satellites in the future.
Last item is international cooperation. KARI joined IADC in 2014 and have been participated steering and working groups. And we performed several IADC re-entry test campaign. Last year, Chinese Tiangong-1 was campaign target and we shared the re-entry prediction. Moreover, KARI participated SpaceOps community and space debris conference, such as AMOS, to understand and discuss the global issue and new technologies related to SSA & STM.
As a national space development organization, KARI will proceed major space programs according to long-term space development plan. Also, Towards Long-term Sustainability of Space Activities, KARI keeps on conducting the SSA & STM related research activities, especially conjunction assessment, radar measurement facilities, the basic research on active debris removal, and the disposal maneuver plan for satellites. KARI pursues the expansion research capacity from typical SSA area to STM area based on controllability and observability on space assets.
Date of Conference: September 17-20, 2019
Track: Space Situational Awareness