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James Webb Space Telescope Orbit Determination AnalysisThe James Webb Space Telescope (JWST) is designed to study and answer fundamental astrophysical questions from an orbit about the Sun-Earth/Moon L2 libration point, 1.5 million km away from Earth. This paper describes the results of an orbit determination (OD) analysis of the JWST mission emphasizing the challenges specific to this mission in various mission phases. Three mid-course correction (MCC) maneuvers during launch and early orbit phase and transfer orbit phase are required for the spacecraft to reach L2. These three MCC maneuvers are MCC-1a at Launch+12 hours, MCC-1b at L+2.5 days and MCC-2 at L+30 days. Accurate OD solutions are needed to support MCC maneuver planning. A preliminary analysis shows that OD performance with the given assumptions is adequate to support MCC maneuver planning. During the nominal science operations phase, the mission requires better than 2 cm/sec velocity estimation performance to support stationkeeping maneuver planning. The major challenge to accurate JWST OD during the nominal science phase results from the unusually large solar radiation pressure force acting on the huge sunshield. Other challenges are stationkeeping maneuvers at 21-day intervals to keep JWST in orbit around L2, frequent attitude reorientations to align the JWST telescope with its targets and frequent maneuvers to unload momentum accumulated in the reaction wheels. Monte Carlo analysis shows that the proposed OD approach can produce solutions that meet the mission requirements.
Document ID
Acquisition Source
Goddard Space Flight Center
Document Type
Conference Paper
Yoon, Sungpil
(AI Solutions, Inc. Lanham, MD, United States)
Rosales, Jose
(AI Solutions, Inc. Lanham, MD, United States)
Richon, Karen
(NASA Goddard Space Flight Center Greenbelt, MD United States)
Date Acquired
November 14, 2014
Publication Date
May 2, 2014
Subject Category
Report/Patent Number
Meeting Information
Meeting: International Symposium on Space Flight Dynamics
Location: Laurel, MD
Country: United States
Start Date: May 2, 2014
End Date: May 9, 2014
Sponsors: Johns Hopkins Univ.
Funding Number(s)
OTHER: 32414-3
Distribution Limits
Public Use Permitted.
Libration Point Orbit
Orbit Determination
James Webb Space Telescope
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