The Spacecraft Bus is the primary support component of the James Webb Space Telescope, that hosts a multitude of computing, communication, propulsion, and structural parts, bringing the different parts of the telescope together.
Along with the Sunshield, it forms the spacecraft element of the space telescope.
The other two major elements of the JWST are the Integrated Science Instrument Module (ISIM) and the Optical Telescope Element (OTE).
Region 3 of ISIM is also inside the Spacecraft Bus; region 3 includes ISIM Command and Data Handling subsystem and the MIRI cryocooler.

The Spacecraft Bus is connected to Optical Telescope Element via the Deployable Tower Assembly, which also connects to the sunshield.

The structure of the Spacecraft Bus must support the 6.5-ton space telescope, while it itself weighs 350 kg (about 770 lb).
It is made primarily of graphite composite material.
It was assembled in California by 2015, and after that it had to be integrated with the rest of the space telescope leading up to its planned 2021 launch.
The bus can provide pointing of one-arcsecond and isolates vibration down to two milliarcseconds.

The Spacecraft Bus is on the Sun-facing "warm" side and operates at a temperature of about 300 K. Everything on the Sun facing side must be able to handle the thermal conditions of JWST's halo orbit, which has one side in continuous sunlight and the other in the shade of the spacecraft sunshield.

Another important aspect of the Spacecraft Bus is the central computing, memory storage, and communications equipment.
The processor and software direct data to and from the instruments, to the solid-state memory core, and to the radio system which can send data back to Earth and receive commands.
The computer also controls the pointing and moment of the spacecraft, taking in sensor data from the gyroscopes and star tracker, and sending the necessary commands to the reaction wheels or thrusters depending.
The Spacecraft Bus is the primary support component of the James Webb Space Telescope, that hosts a multitude of computing, communication, propulsion, and structural parts, bringing the different parts of the telescope together. Along with the Sunshield, it forms the spacecraft element of the space telescope. The other two major elements of the JWST are the Integrated Science Instrument Module (ISIM) and the Optical Telescope Element (OTE). Region 3 of ISIM is also inside the Spacecraft Bus; region 3 includes ISIM Command and Data Handling subsystem and the MIRI cryocooler.
The Spacecraft Bus is connected to Optical Telescope Element via the Deployable Tower Assembly, which also connects to the sunshield.
The structure of the Spacecraft Bus must support the 6.5-ton space telescope, while it itself weighs 350 kg (about 770 lb). It is made primarily of graphite composite material. It was assembled in California by 2015, and after that it had to be integrated with the rest of the space telescope leading up to its planned 2021 launch. The bus can provide pointing of one-arcsecond and isolates vibration down to two milliarcseconds.
The Spacecraft Bus is on the Sun-facing "warm" side and operates at a temperature of about 300 K. Everything on the Sun facing side must be able to handle the thermal conditions of JWST's halo orbit, which has one side in continuous sunlight and the other in the shade of the spacecraft sunshield.
Another important aspect of the Spacecraft Bus is the central computing, memory storage, and communications equipment. The processor and software direct data to and from the instruments, to the solid-state memory core, and to the radio system which can send data back to Earth and receive commands. The computer also controls the pointing and moment of the spacecraft, taking in sensor data from the gyroscopes and star tracker, and sending the necessary commands to the reaction wheels or thrusters depending.
James Webb Space Telescope