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Today, new constellations of over 1,000 such satellites have been proposed. By the next decade, the number of them in orbit could increase ten-fold - from about 2,000 to 20,000, according to the World Economic Forum. But why?

High risk, high return?

Technology breakthroughs have driven costs down, opening the market to new commercial players, such as SpaceX, who haven’t traditionally had a presence in space.

Typically operating in low Earth orbit (LEO) of 1100-1300km above the Earth’s surface, these small satellites can be built for a tiny fraction of the price of a traditional spacecraft, largely due to advances in miniaturisation and commercial off the shelf (COTS) technology. But the operational lifetimes of these small satellites is short: one to five years, compared to a traditional 10 to 15.

Nevertheless, their proximity to the surface means that LEO-to-Earth communication can be achieved in 20% of the time (latency) of what is achieved via geostationary satellites. A constellation of satellites at this altitude offers shorter revisit times and greater coverage for the same mission costs. And the defence industry has its own connectivity challenges, being heavily reliant on the more traditional radiofrequency spectrum, which has much slower transmission rates.

The opportunities afforded - whether that be building a space-enabled Internet of Things (IoT) network, global broadband access, or your own Earth observation system - allows companies to tap into the ‘NewSpace’ phenomenon. Never before have organisations had so much control over the process, from the design of a system all the way through to its orbital operations.

The age of optical mesh

While accelerating Earth-to-satellite signals is undeniably promising, perhaps a more significant development will be the possibility of cross-linking (or ‘meshing’) thousands of satellites with lasers that can send and receive information - in order to form global optical mesh networks. This is provided by the transmission of light (visible or infrared) in free-space, where there is no need for optical fibres.

Today the use of optical technology via fibre-optic cables connects much of the world. But such ground-based cables aren’t always best. A digital signal over a standard fibre-optic link between New York and London is a 76 millisecond round trip. The same signal routed through a space-based optical mesh network could theoretically do this in 50 milliseconds, according to research from University College London.

Optical transmissions are virtually impossible to intercept. They also don’t compete for space on the increasingly congested electromagnetic (EM) spectrum, and the optical band is unlicensed, so it’s easy to get going. In fact, the optical communication and networking equipment market was valued at $18.9 billion in 2020, but is set to reach $27.8 billion by 2025, according to Markets and Markets.

Despite all this, meshing between thousands of small satellites across many orbits, whilst connecting to ground-based networks is far from simple, and there are hurdles to overcome.

Co-operation is key

Whilst the business of small satellite constellations is evidently high-risk, high-reward, the story of the bankruptcy of satellite company OneWeb shows the impact of getting it wrong. Even still, faith remains: the UK government and India’s Bharti Global both put $500 million into a joint $1 billion takeover to rescue OneWeb in July 2020.

With the field expanding at such a rate, with such versatility available, the temptation for some operators might be to ‘go it alone’ in order to get ahead. Successful implementation of constellations requires a cohesive effort from a broad range of (often competing) global stakeholders. This won’t happen quickly, but if successful, the outcomes could one day be magnificent.