An updated version of the UCS Satellite Database has been released, including launches through 1-31-2011. The total number of active satellites is currently 957. A quick overview of how those satellites are distributed in various ways is included here:
This update marks 5 years that we’ve been preparing this database. I thought I’d take the opportunity to see how the number of active satellites has changed since then. The February 11, 2006 database included 813 satellites. This number has risen steadily, but slowly:
While it is always clear when a satellite has been launched, determining with certainty that a satellite is no longer actively operating can sometimes take somewhat longer, so there can be a lag in taking those satellites out. This can create small artifacts in the plot. For example, the dip in April 2009 did not reflect a surge in satellite failures. Instead, we had suspected many of these satellites were no longer operational, but at that point found enough sources to confirm that.
But all in all, the trend has been remarkably steady.
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