세미나 및 이벤트

GRACE (Gravity Recovery and Climate Experiment) Mission: Overview and Simulation

세미나 날짜 2001-01-04
작성자
윤두희
작성일
2001-01-04
조회
1130
1.제목: GRACE (Gravity Recovery and Climate Experiment) Mission: Overview and Simulation Analysis


2.연사:Dr. Jeongrae Kim (Research Engineer/Scientist Associate IV, University of Texas at Austin)


3.일시:2001년 1월 8일 (월요일) 오후 1시 30분


4.장소:301동 1512호


5.내용:


The Gravity Recovery and Climate Experiment (GRACE), selected under the NASA Earth System Science Pathfinder (ESSP) program, is a dedicated spaceborne mission to map the gravity field with unprecedented accuracy. The satellites are planned to launch in late 2001 over a lifetime of approximately 5 years. It consists of two satellites, co-orbiting in nearly polar orbit, at approximately 300-500 km altitude, separated by 100-500 km along track.


Primary measurements are the range change between the two satellites using dual one-way microwave ranging system. These measurements are combined with accelerometer and GPS measurements. Accelerometer measurements are for estimating the non-gravitational acceleration effect on the range changes. The GPS measurements are used for providing satellite orbit and time-tag information.


Comprehensive simulation models for these major instruments have been developed to analyze the effects of the primary error sources on the orbit and gravity estimation. These results have been used for the satellite instrument and mission design process. The comprehensive error models made it possible to obtain realistic results. The effects of other design parameters, e.g. orbit conditions, have been analyzed as well.


This presentation describes the instrument error models with an overview of the GRACE mission. Expected orbit and gravity estimation accuracy from the simulation results will be discussed. Sensitivity studies of other design parameters will be discussed.





6. 연사 약력 :


1991 B.S. Aerospace Engineering, Seoul National University, Korea


1993 M.S. Aerospace Engineering, Seoul National University, Korea


2000 Ph.D. Aerospace Engineering, University of Texas at Austin, USA


2000-Present Research Engineer/Scientist Associate IV Center for Space Research, University of Texas at Austin, USA





7. 연락처 : 기계항공공학부 기창돈 교수 (전화 : 880-1912)