tor26 missing certificate messages today

[Scott Bennett <bennett@xxxxxxxxxx>]

     This afternoon my tor server began logging the following messages:

Dec 09 15:10:18.474 [notice] We're missing a certificate from authority tor26 with signing key 0000000000000000000000000000000000000000: launching request.
Dec 09 15:11:19.530 [notice] We're missing a certificate from authority tor26 with signing key 0000000000000000000000000000000000000000: launching request.
Dec 09 15:12:18.357 [notice] We're missing a certificate from authority tor26 with signing key 0000000000000000000000000000000000000000: launching request.

These messages continued at the rate of approximately one per minute until the
final one:

Dec 09 16:03:08.509 [notice] We're missing a certificate from authority tor26 with signing key 0000000000000000000000000000000000000000: launching request.

     Does anyone know the reason for these messages?  And the reason why they
eventually stopped appearing 53 minutes later?


                                  Scott Bennett, Comm. ASMELG, CFIAG
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