We begin a new series of blog posts by our team members, explaining some of the concepts behind our business model and technology.
Cubesats are a classification of small satellites that are measured in a volumetric called a U, This U is a cube of dimensions 10cm x 10cm x 10cm (hence the term cubesat) and a satellite can be built of a set number of U’s. Such as a 1U communications node, a 3U earth observation platform or a larger 12U space telescope.
To understand how the cubesat concept evolved we need to understand the traditional design philosophy of satellites that has only changed in the last decade. Back when the first satellite was launched in 1957 we were still in an era of analogue electronics where you would require a single vacuum tube the size of your fist to have a single transistor in your circuit, compared to the latest processors today that have billions of them over a surface area equal to your fingernail. This means that for early satellites to have any form of capability they would need to be large in size for even basic radio communications.
Over the past decade consumer electronics have become small, cheap and most importantly: reliable. This means you can get high capability in a small package, which is important when you consider that per kilogram it would cost you up to 35,000 US dollars to get anything into orbit. This led to the development of the small satellite classification where a system that can fit in your hand can be sent into orbit and can be a communications platform, a device that can track forest fires or even a development platform where new technology can be tested in space at a reduced cost. Such as our mission NOVA.
The big advantages that cubesats (and by definition small satellites) bring to the table is cost to market, for previous missions you would have to use space grade equipment which is traditionally high cost and size and following that chain would lead to a larger satellite that would require a dedicated launch, again leading to higher costs. In a smaller size using off the shelf components costs can be saved, and multiple cubesats can be carried in a single launcher under a rideshare programme which further reduces costs.
Due to the lower capability of cubesats compared to the larger projects led by the international space agencies they are used heavily in commercial applications, this means that they operate in low earth orbit (LEO) where the majority of earth observation and communication satellites are based, although LEO is classed as any attitude below 2000km this tends to be more in the 300km ballpark. Small satellites are seldom used in higher orbits such as geostationary orbit (GSO) due to the cost of a dedicated heavy launcher that can send larger payloads to such altitude in addition to these higher orbits being more restricted due to their unique properties.
Mark Perkins