Skip to main content

Currently Skimming:

10 Spacecraft Anomalies
Pages 72-76

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.

From page 72...
... "Unknown" is attributed to the vast majority of anomaly cases, since it is so difficult to determine exactly what happens in space without dedicated instrumentation to provide insights from on-orbit encounters that adversely affect satellite operations. There may be times when an "unknown" is erroneously attributed to a meteoroid or orbital debris event.
From page 73...
... NASA scientists examined the frayed end of the guidewire with a scanning electron microscope, discovering damage to it in the form of melting that was characteristic of fusing from the impact of a meteoroid or orbital debris. Further examination using a narrow-focus electron microprobe and energy dispersive x-ray spectrometer to analyze the chemical elements in the impact zone resulted in the conclusion that the damage was caused by orbital debris, not a meteoroid.
From page 74...
... It is this "residual risk" that may be better characterized by clearer, consistent recording, analysis, reporting, and sharing of satellite anomalies, since such orbital encounters cannot be observed from the ground. However, even the lower end of the range of sizes at which particles might be causing spacecraft anomalies is highly uncertain because of the wide variety of space system designs encountered, varying impact speeds and directions, and a wide range of particle characteristics.
From page 75...
... This issue is also discussed in Chapter 3, "Orbital Debris Modeling and Simulation." Just as the Orbital Debris Program Office works to significantly increase measurements of the sub-5-mm population through returned samples and of the 1- to 10-cm population through Haystack measurement campaigns, developing standard processes for recording, analyzing, reporting, and sharing satellite anomalies will provide a rich source of information not only on the environment flux but also on the effects on satellite systems of impacts by particles in the 5 mm to 10 cm size range. An examination performed on a limited set of records for the past 20 years for satellite anomalies identified discrepancies in the available data that may make any post facto analysis of limited use, and it is essential that NASA now prepare for the future and establish a means to change this situation going forward.
From page 76...
... Eventually, this effort could provide data to upgrade current MMOD models -- the Meteoroid Environment Model, Orbital Debris Environment Model, and BUMPER.

This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More information on Chapter Skim is available.