Darpa is working with Lockheed Martin on the first stage of satellite integration for project blackjack, a military low earth orbit (LEO) satellite constellation. Harry Lye finds out more from the programme leaders.
In April 2020, Lockheed Martin was awarded a $5.8m contract for the first phase of satellite integration on DARPA’s Blackjack programme. Lockheed Martin will manage interfacing between Blackjack’s bus, payload and Pit Boss in the run-up to the launch of a demonstration constellation in 2021-22.
As traditional military satellites are expensive to replace, DARPA is betting on low earth orbit constellations as a means to get military hardware into orbit at a lower cost with the Blackjack programme. Such a system would remove single points of failure both in space and on the ground. It would also mean a shift towards on-orbit processing, where the Blackjack constellation can shoulder the processing burden of ground-based systems.
“The advantage of on-orbit processing is that it brings resilience in a proliferated LEO constellation, DARPA Blackjack programme manager Paul “Rusty” Thomas told us. “Putting distributed processing in space eliminates a single point of failure in space or on the ground.”
LEO vs GEO satellites
The US is looking to achieve a number of goals with a military low earth orbit constellation, ranging from cost to latency, says Lockheed Martin programme director for advanced missile defence Julie Pecson.
“There are advantages and disadvantages of all orbital regimes,” she tells us. “For LEO constellations, data latency is reduced because the satellites are closer to the earth compared to geosynchronous earth orbit (GEO) where traditional military satellites fly. Also, LEO satellites are generally smaller in size because they require less propulsion and less power.”
However, due to operating at a higher altitude, one GEO satellite can cover the same area as several LEO satellites. This means that more LEO satellites are needed to provide the same level of service to the military. This disadvantage can be somewhat an advantage in itself, though.
“Due to their proximity to earth, more LEO satellites are required to perform similar GEO missions,” Pecson explains. “However, the numerous spacecraft required in LEO provide an inherent constellation-level resiliency advantage over traditional military constellations relying on a small number of spacecraft. Lockheed Martin Space performs mission analysis to determine the best orbit and constellation architecture to support the mission.”