What Is a Satellite Bus and Why It Is So Important?

Satellite bus? What is that? No, it is not a flying bus that is orbiting the Earth! It is the body of the satellite which houses all of the components, including the payload. It is the infrastructure that protects and allows the satellite to carry out its mission. In this article, we will look at the satellite bus definition, purpose, how it works, and more!

What Is a Bus in a Satellite?

A satellite is made up of two components: a satellite bus and a payload. The bus refers to the physical structure of the spacecraft, which contains the scientific equipment and payload, while the payload refers to the components that perform the mission of the satellite. For most spacecraft, the payload is the camera, sensor, antenna, and other communication systems. The name comes from the fact that the spacecraft body transports the spacecraft’s payload into space just like a standard bus transports passengers.

The satellite bus size can vary widely. There are buses that weigh under 1kg, while another giant spacecraft can weigh over 6000kg! The spacecraft bus in the satellite can also be designed in various styles and shapes. The most common design is a square or rectangular box with two solar-paneled wings on either side.

The standard satellite bus configuration features the following components:

●  Command and data handling

●  Communications system

●  Electrical power system

●  Propulsion

●  Thermal control

●  Attitude control system

●  Navigation

The spacecraft body is critical in housing and protecting the payload. Without a well-designed bus, the spacecraft will not be able to successfully carry out its position. Despite the satellite bus being the body of the spacecraft, its cost is only around 25% of the total spacecraft cost.

What Is the Purpose of a Satellite Bus?

The main purpose of the satellite bus is to protect and transport the payload and scientific equipment to the desired location and allow it to carry out its position. For example, for an Earth Observing satellite, the role of the body is to get the camera into space and allow it to take images of the Earth and transmit them.

The payload and the satellite bus have an equally important role and rely on each other to carry out the mission. Without the spacecraft body, the payload would not be able to reach space, and it would not be able to take images and transmit them. At the same time, without the payload, the satellite bus would just be space junk, orbiting around the Earth and not providing any useful function. This is why satellite bus manufacturers need to get the design of the payload and bus correctly; otherwise, their spacecraft will not be able to complete the mission.

The perfectly designed satellite body is lightweight but can still handle the intense pressure during launch and traveling in space. During the design process, manufacturers have to consider weight, cost, functionality, and longevity. The spacecraft body must have a firm outer layer that protects the spacecraft from collisions and debris. It needs to be able to withstand the radiation from the sun and have thermal blanketing to protect the payload from extreme temperatures.

How Does Satellite Bus Work?

A satellite bus is launched into space via a rocket or space shuttle. Once they are released from the rocket, spacecraft start orbiting the Earth after finding a speed in balance with a pull from the Earth’s gravity. Once in orbit, a spacecraft can start fulfilling its mission, whether that is taking pictures of the Earth, monitoring climate, crops, or powering the internet or TV.

A spacecraft is capable of sending and receiving signals from Earth due to its antenna communication system. The spacecraft uses radio waves to transmit data via the Big Space Network. The majority of the satellite bus power comes from the solar-paneled wings, which are attached to either side of the spacecraft. The spacecraft also contains batteries that are recharged thanks to the enormous power of the sun and do not rely on fuel. Some spacecraft carry fuel, but this is only used in extreme cases such as avoiding debris and is not required to orbit the Earth.

Summing it up

The satellite bus is the physical structure and body of the spacecraft. Its role is to transport the payload and scientific equipment into space and protect it. It plays a critical supporting role in allowing the payload to carry its function. Without the bus, the spacecraft would never make it to space, and we would never have satellite images! Now you know key satellite bus details and how it works, please comment below on what you think the future of the satellite industry will look like!