Despite a five-fold increase to available electrical power with the first of four solar arrays along the start of the Integrated Truss Structure, the ISS crew hadn’t much room for experiments beyond the smaller bays available for them in Zvezda.
On February 7, 2001, that was going to change in a big way. With STS-98, Shuttle Atlantis launched carrying Destiny, a huge laboratory larger than two nodes in volume that would increase the living volume of the station by over 40 percent.
Destiny was designed to hold up to twelve experiment racks. On arrival, it came with five racks filled. These racks were primarily additional life support, electrical and climate control resources for the first American and later international modules, supplementing what was provided by Zarya and Zvezda.
Atlantis was the second manned visiting vehicle to the manned ISS from the perspective of the Expedition 1 crew, which had been on board for over 3 months. STS-97 had arrived a month or so prior to install the first solar array truss needed to power the new laboratory.
To get Destiny attached required some rearranging. As with Endeavour on STS-97, Atlantis was docked on the nadir (bottom) Pressurized Mating Adapter (PMA) 3 on Node 1, Unity. PMA 2 was removed to free up the forward CBM port of the Unity node that was intended for the new laboratory. After Destiny was in place, PMU 2 was placed at its new interim location on Destiny’s forward CBM port.
During the STS-98 mission, ground controllers also activated the station’s control rate gyros included with the Z1 Truss. This saved the use of propellants in keeping the station oriented relative to the sun and earth.
Compared to the somewhat smaller utilitatian compartments of Zarya and Zvezda, the Destiny module was incredibly roomy. Over time, a bit of that room would make way for experiment racks, computer stands, and other needs.
More supplies for the station were also offloaded to the crew. The laboratory’s power, cooling, air circulation and other systems were activated for the first time. Possibly the most popular part of Destiny was its large observation window.
With STS-98’s mission complete, the Expedition 1 crew were slated for one more month aboard before STS-102 arrived with fresh supplies delivered in a different way, as well as a fresh station crew.
Next: Assembly 5A.1.