The Magellan spacecraft had the total weight 3,453 kilograms and consisted of
(1) Antennas (high-, medium-, and low-gain).
(2) Forward equipment module.
(3) Equipment bus.
(4) Solar panels.
(5) Propulsion module.
(6) Solid-rocket orbit-insertion motor.
High-gain antenna (HGA) was parabolic in shape. The dish of the antenna was made of strong, lightweight, graphite- epoxy sheets mounted to an aluminum honeycomb for rigidity. Functions of this antenna was –
2) Transmission of radar data,
3) Reception of radio signals from Earth, and
4) Transmission of engineering health data to Earth.
The medium-gain antenna (MGA) was cone-shaped structure mounted to the topside of the equipment bus.
The low-gain antenna (LGA) was mounted on a platform held by struts above the HGA.
Both these antennas were useful during the malfunctioning of high gain antenna.
Forward Equipment Module
The forward equipment module was used to store radar electronics, radio telecommunications equipment, certain attitude-control equipment, batteries, and the power- conditioning unit.
It was mainly made up of alloy of aluminium so as to make it light in weight and it was covered with mirror so as to reflect high frequency waves and heat waves coming from the sun.
Immediately below the FEM was the 10-sided equipment bus, which acted as a enclosure for electronics. An opening in the middle of the ring of compartments contained the hydrazine fuel tank for the liquid-propulsion system.
The bus compartments contained the flight computers, the input/output interface between the computers and Magellan subsystems, tape recorders, solar-array controls, solid-state bulk memory, and pyrotechnic control electronics.
The two solar panels were used as a source of power, which used to provide 1200 watts of power.
The propulsion equipment included a 24-thruster liquid-propulsion module and the solid-rocket motor (SRM) used for orbit insertion. The propulsion-module structure provided a precisely aligned attachment of the SRM, as well as the liquid-propellant thrusters, which were needed for trajectory/orbit corrections, attitude control during orbit insertion, and other functions.
Let us the different subsystems of the Magellan spacecraft