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The 'Unity' connecting module was the first U.S.-built component of the International Space Station.
It is cylindrical in shape,
with six berthing locations (forward, aft, port, starboard, zenith, and nadir) facilitating connections to other modules.
Unity measures 4.57 meters (15 ft) in diameter, is 5.47 meters (18 ft) long,
and was built by The Boeing Company in a manufacturing facility
at the Marshall Space Flight Center in Huntsville, Alabama.
Sometimes referred to as 'Node 1', Unity is the first of three such connecting modules that will be
part of the completed station.

Contents

Launch and initial berthing

Connections to other station components

Details

Other nodes

Specifications

References

Launch and initial berthing

Unity was carried into orbit
as the primary cargo of the Space Shuttle ''Endeavour'' on STS-88,
the first Space Shuttle mission dedicated to assembly of the station.
On December 6, 1998, the STS-88 crew mated the aft berthing port of Unity
with the forward hatch of the already orbiting Zarya module.
(Zarya was a mixed Russian-US funded and Russian-built component
launched earlier aboard a Russian Proton rocket from Baikonur, Kazakhstan.)
This was the first connection made between two station modules.

Connections to other station components

In addition to connecting to the Zarya module, Unity currently connects to the U.S. Destiny Laboratory Module (added on STS-98), the Z1 truss (an early exterior framework for the station added on STS-92), the PMA-3 (also added on STS-92), and the Quest Joint Airlock (added on STS-104). In addition, the Leonardo and Raffaello Multi-Purpose Logistics Modules have each been berthed to Unity on multiple missions. Node 3, with its multi-windowed cupola, will be attached to Unity during the STS-132 mission.

Details

Essential space station resources such as fluids, environmental control and life support systems, electrical and data systems are routed through Unity to supply work and living areas of the station. More than 50,000 mechanical items, 216 lines to carry fluids and gases, and 121 internal and external electrical cables using six miles of wire were installed in the Unity node. Unity is made of aluminum.
Prior to its launch aboard ''Endeavour''
conical Pressurized Mating Adapters (PMAs) were attached to the aft and forward berthing mechanisms of Unity.
Unity and the two mating adapters together weighed about 25,600 pounds.
The adapters allow the docking systems used by the Space Shuttle and by Russian modules to attach to the node's hatches and berthing mechanisms. PMA-1 now permanently attaches Unity to Zarya, while PMA-2 provides a Shuttle docking port. Attached to the exterior of PMA-1 are computers, or multiplexer-demultiplexers (MDMs), which provide early command and control of Unity. Unity also is outfitted with an early communications system that allows data, voice and low data rate video with Mission Control, Houston, to supplement Russian communications systems during the early station assembly activities.
PMA-3 was attached to Unity's port hatch by the crew of STS-102.^[1]

Other nodes

The two remaining station connecting modules, or nodes, are being built in Italy by Alenia Aerospazio,
as part of an agreement between NASA and the European Space Agency (ESA).
'' Harmony'' (formerly known as Node 2) and Node 3 will be slightly longer than the Unity node, measuring almost 6.4 meters (21 ft) long.
In addition to their six berthing ports each will hold eight International Standard Payload Racks (ISPRs).
Unity, in comparison, holds four ISPRs.
ESA is building nodes 2 and 3 as partial payment for the launch aboard the Shuttle
of the Columbus laboratory module, and other ESA equipment.

Specifications

★ Length: 5.49 m

★ Diameter: 4.57 m

★ Mass: 11,612 kg

References

★ http://spaceflight.nasa.gov/spacenews/factsheets/pdfs/unity.pdf

★ Video tour of the module, filmed in July 2007 by Clayton Anderson
1.
Status Report # 07