Peter B. de Selding: Out-of-Control Satellite Threatens Other Nearby Spacecraft. space.com, 3. Mai 2010, abgerufen am 4. Mai 2010 (englisch): „Depending on their position at the time of failure, these satellites tend to migrate toward one of two libration points, at 105 degrees west and 75 degrees east. Figures compiled by XL Insurance of New York, an underwriter of space risks, say that more than 160 satellites are gathered at these two points“