The Speed of Light Club was a club for Starfleet personnel. The prerequisite for entering the club was that a Starfleet member would fly three hundred thousand kilometers per second in level flight on a Starfleet cruiser.
On April 4, 2327, Jean-Luc Picard was inducted in as a member after he completed the flight on the USS Leondegrance. He received a certificate from the club with the signatures of the honorary president and honorary vice president. This certificate was stored in Picard's section of the quantum archive at the Starfleet Archive Museum. (PIC: "Remembrance")
Production designer John Eaves created the Speed of Light Club certificate, basing it on the US Navy's real Thousand Mile-Per-Hour Club. [1](X)
The certificate was one of the props displayed at Comic Con's exhibit Jean-Luc Picard: The First Duty in the summer of 2019. [2]