Flight Dynamics Facility Research Articles

New EUMETSAT polar system attitude monitoring software

The original attitude monitoring software of the EUMETSAT Polar System Flight Dynamics Facility allowed the computation of mean attitude misalignment and AOCS sensor biases in a given processing time, assuming a nominal attitude law with constant misalignments. This system has been enhanced, computing the actual attitude evolution from the angular velocity reconstructed from the gyro data and estimating all the attitude and sensor parameters with a batch least square method based on the observations provided by the on- board optical sensors. The resultant attitude evolution can be propagated after a spectral analysis of the misalignment evolution through a Fast Fourier Transform. This software has been integrated in the Metop Flight Dynamics System and it is currently being used in routine operations to estimate the satellite short term attitude evolution (only one orbit of gyro data are daily available) providing a very useful information on the pointing stability of the platform.

STEREO Ground Segment, Science Operations, and Data Archive

Vitally important to the success of any mission is the ground support system used for commanding the spacecraft, receiving the telemetry, and processing the results. We describe the ground system used for the STEREO mission, consisting of the Mission Operations Center, the individual Payload Operations Centers for each instrument, and the STEREO Science Center, together with mission support from the Flight Dynamics Facility, Deep Space Mission System, and the Space Environment Center. The mission planning process is described, as is the data flow from spacecraft telemetry to processed science data to long-term archive. We describe the online resources that researchers will be able to use to access STEREO planning resources, science data, and analysis software. The STEREO Joint Observations Program system is described, with instructions on how observers can participate. Finally, we describe the near-real-time processing of the “space weather beacon” telemetry, which is a low telemetry rate quicklook product available close to 24 hours a day, with the intended use of space weather forecasting.

Now & Then: Ann Wagner, Mechanical Engineer: A Brief History of Mechanical Engineering

Now … Ann Wagner is a Mechanical Engineer in the Facility Management Division of the Facilities Engineering and Technical Services at the 1121-acre Goddard Space Flight Center in Greenbelt, Maryland. She designs, improves, repairs, and replaces systems that deliver utilities-heat, light, cooling, water, and power-to the fifty buildings there. Goddard was established as the National Aeronautics and Space Administration's first space-flight center in 1959. Its mission, “to expand knowledge of the Earth and its environment, the solar system and the universe through observations from space,” tells the significance of the work here, which is to research and to support communication of all kinds throughout the world. The Hubble Space Telescope Control Center; the Flight Dynamics Facility, which supports space-shuttle operations; and vast communication networks are among the many resources at Goddard that simply cannot be shut down for some period of time for repairs to a utility cable, pipe, or pump.