I attended the International Astronautical Congress in Adelaide in October 2017 and sat in on a presentation on the future of humanity in space by SpaceX CEO Elon Musk. He was talking about a large fully reusable rocket, called ‘BFR’ at the time, which was designed to revolutionise space access and, most importantly in Musk’s view, to realise his long-held goal of colonising Mars, making humans a multi-planet species.

Apart from being fully reusable, the BFR—now ‘Starship’—was designed to launch over 100 metric tonnes of payload—cargo or astronauts—into low earth orbit (LEO) and, with on-orbit refuelling, send that payload on to the moon, Mars or even beyond. Its reusability promised much lower launch costs and, depending on how many Starships were to be built, full reusability opened up the prospect of regular space access at around US$2 million per launch. In comparison, NASA’s Space Launch System, which is billions of dollars over budget and years behind schedule, will fly once a year, isn’t reusable and costs around US$2 billion per launch.

Fast forward to now, and SpaceX has just successfully flown—and landed—a test vehicle called ‘Starship SN15’. That comes after several tests ended in fiery explosions and spectacular crashes. The successful SN15 test is a real breakthrough for SpaceX, and opens up a path for additional tests in coming months.

SpaceX’s approach with Starship development is following that it used to develop its Falcon 9 partly reusable launch vehicle. The methodology involves developing capability through operational testing, which saw numerous failures with Falcon 9 rockets before they were perfected. They’re now flying regularly. The next steps with Starship are further tests to higher altitudes, and then orbital flights using the ‘Super Heavy’ booster stage as early as July, with full operational service by 2023.

Starship opens up the prospect of rapid and regular low-cost, high-volume space access. The sheer capacity of the vehicle means that it can deploy very large payloads, such as big satellites or space station modules. Alternatively, large numbers of smaller satellites can be deployed in one launch.

For human spaceflight, Starship will play a pivotal role in NASA’s Project Artemis, with SpaceX being awarded a contract to provide the landing system to get astronauts from the Gateway lunar orbit station to the moon, though a protest lodged by competitors has led to the contract being paused pending arbitration. Musk also advocates Starship as the key capability for getting people to Mars in coming decades.

The potential national security and military applications offered by Starship also need to be considered. SpaceX has promoted Starship as a means of rapid point-to-point transport across the earth, carrying either troops or cargo to a distant operational deployment within 30 minutes. Starship’s payload capacity would provide the equivalent of a C-17 cargo aircraft’s load anywhere on the planet within an hour. There are obvious risks in this idea, especially  the challenge of distinguishing incoming Starships carrying troops or cargo from ballistic missiles. The potential for miscalculation and escalation in a crisis would be considerable.

Perhaps a better option would be the use of Starship to rapidly deploy large military payloads into orbit, to augment or reconstitute satellites destroyed by adversary counterspace capabilities. There’s also increasing debate within the US Space Force over the moon and cislunar space as a region of military competition, especially in light of Chinese and Russian space activities.

The Center for Strategic and International Studies’ Defense against the dark arts in space report postulated a Chinese attack on US communication satellites in geosynchronous orbit from the cislunar region, and greater interest is emerging in extending space domain awareness out to cislunar space. The Defense Advanced Research Projects Agency project ‘Draco’ is designed to develop a nuclear-powered spacecraft for that role. It’s the sort of payload that Starship could easily deliver into lunar orbit, or to a Lagrange point—where earth’s and moon’s gravity are balanced— allowing long-endurance deployments at minimal cost.

The key importance of SpaceX’s Starship is the promise of low-cost, rapid space access to deploy large payloads into orbit. Critical to that is reusability, allowing rapid turnaround and a high launch cadence. That’s the game changer, and other US companies such as Blue Origin and Rocketlab, Chinese companies, and Europe’s Arianespace are now pursuing reusable launch vehicle designs.

The case for reusability for Australian launch providers needs to be balanced by the potential low cost of production of rocket hardware, including engines, and the requirements dictated by payload mass. Smaller satellite payloads of the type that Australia is likely to pursue in coming years aren’t likely to justify the extra expense for local space launch providers of developing a reusable rocket. It makes more sense to emphasise the low-cost, rapid production of expendable launch vehicles to match expected demand from either local or overseas customers. However, once Australian companies begin developing larger rocket systems, as they certainly will, reusability needs to be considered as an option, particularly for heavier payloads.

That may open up new opportunities for the Australian Defence Force’s use of sovereign launch capabilities. It’s possible that 10 years from now the ADF Space Command could manage sovereign-controlled satellites and be able to rely on sovereign launch capability provided by Australian commercial launch providers. In that scenario, if the ADF urgently required additional space support during a crisis, it could mandate rapid launches of stockpiled small satellites to meet its communications and intelligence, surveillance and reconnaissance requirements. If Australia were to be faced with an adversary counterspace campaign attacking our larger satellites in geosynchronous orbit, the ADF could quickly direct an Australian company to launch additional satellites to fill gaps.

Waiting months for  a launch wouldn’t be an option, as our forces operating in the air, sea and land domains would need space support urgently. Relying on a US launch provider such as SpaceX would be risky, as they are likely to be fully tasked with supporting US operational requirements in a crisis. An Australian launch provider will need to be able to deploy satellites quickly—and locally developed reusable launchers might be the best way to do that.