connected by PMA-1. PMA-2 PMA-2 is mounted on the forward port of the Harmony connecting node, and was used when Space Shuttle orbiters docked at the ISS. It was outfitted with Station-to-Shuttle Power Transfer System (SSPTS) hardware to allow the shuttles to stay docked longer to the space station. PMA-2 was moved several times as part of the space station assembly process. It was originally connected to the forward hatch of Unity, but when STS-98 delivered the Destiny module in February 2001, PMA-2 was moved to the berthing ring of the Z1 truss so that Destiny could be berthed to the forward hatch of Unity. PMA-2 was finally moved to the forward hatch of Destiny. (The removal of PMA-2 from Unity was the first time the CBM had been used to disconnect two ISS components.) After STS-120 had delivered Harmony to the space station in October 2007, Canadarm2 repositioned PMA-2 at the forward port of Harmony on November 12, 2007. Two days later, the combined package of Harmony and PMA-2 was moved to its final location, the forward hatch of Destiny. On July 18, 2016, International Docking Adapter-2 was launched on SpaceX CRS-9. It was attached and permantly connected to the APAS-95 port of PMA-2 during a spacewalk on August 19, 2016. As of 2020, PMA-2 is expected to stay berthed at the forward port of Harmony with the IDA connected for the remaining duration of the ISS. When a shuttle docked with the station, its "final approach [was] at a relative velocity of one-tenth of a foot per second. [As it made] contact with Pressurized Mating Adapter 2 [latches] automatically attached the two spacecraft together. Once relative motion between the spacecraft stopped, [a Shuttle astronaut retracted] the docking ring on [the Shuttle's] mechanism, closing latches to firmly secure the shuttle to the station." PMA-3 PMA-3 was brought to the ISS by STS-92 in October 2000, mounted on a Spacelab pallet. It was initially attached to the nadir (bottom, or Earth-facing) hatch of Unity. About six weeks later, when STS-97 delivered the P6 solar array truss structure, Endeavour docked at PMA-3. When STS-98 moved PMA-2 from Unity to Destiny via the Z1 truss in February 2001, Atlantis was docked at PMA-3. For the remainder of the shuttle's operation, PMA-3 was not used for shuttle dockings. PMA-3 was moved in March 2001 to Unitys port hatch by the crew of STS-102