About Space

Space explained

Space is almost universally considered to be the region surrounding the earth and beyond where atmospheric friction has little or no impact on the motion of objects. The Karman Line, an imaginary boundary located 100km above the mean sea level of earth, is commonly known as the beginning of space.

Orbital space is the region of most interest to this work and comprises a number of bands where satellites can be injected and are subject to the physical laws of orbital motion as first described by Kepler. The motion of satellites in orbital space are largely determined by the gravitational forces generated by the mass of the earth.

Humans also exploit space through short duration sub-orbital missions, whereby the platform does not generate sufficient velocity to escape Earth gravity and enter orbit, and deep space missions where spacecraft enter deep space beyond earth orbit.

As an operating environment, space is challenging and risky. Engineered systems that function in space must contend with near zero vacuums, high energy radiation, extremes in temperature variations and be built to withstand the violence of launch, extreme accelerations, vibration, acoustic loads and atmospheric loads. Whilst reliability has vastly improved in the previous decades, for both spacecraft manufacturing and launch vehicle performance, there is still high risk of complete mission failure during launch and space operations. This drives up the cost of manufacture and makes launch expensive. Insurance and financing can also be challenging and drive the cost of delivery of a space system.

Finally, as a “global commons”, space attracts heavy regulatory attention through international bodies such as the UN and national regulators such as the Australian Space Agency and the Department of Infrastructure, Transport, Regional Development and Communications.

The space sector comprises organisations with specialist skills, facilities and infrastructure that support conceptualising, designing, building, deploying and operating space objects. There is a large, complex and interconnected value chain that enables and supports the space sector. Given the nature of required skills, many organisations that service the space sector, also operate in other sectors, most notably the aircraft industry. The coupling of these two industries is so tight it is often referred to as the aerospace sector.