That wedge is the International Space Station (ISS). The ISS — the most expensive and ambitious engineering project in human history — is where SpaceX began sending cargo in 2012 and humans in 2020. For over a quarter century, first before SpaceX and now because of it, the ISS has been a triumph of science, diplomacy, and persistence. But as the ISS nears deorbit, there is a very real risk of losing trillions of dollars in latent value currently trapped in the ISS and the space industry’s antiquated economic model.

With roughly $250 billion of taxpayer investment — $150 billion to build and $4 billion annually to maintain — the ISS has created immense scientific and technological value. However, if that same capital had been invested in the S&P 500 over the same period, it would be worth over $2 trillion today — ironically, the exact projected market cap of SpaceX.

This comparison is not intended to diminish the intangible value of scientific exploration but to illustrate the significant economic opportunity that remains untapped. By reframing the question, we see that the ISS is an incredible financial asset in need of a value transference mechanism — an economic bridge to liquidate the returns on our investment.

It is important to understand that the current ISS operational approach is rooted in a Cold War-era framework that has served as a beacon for international cooperation and diplomacy, and one that allowed SpaceX to learn, build, iterate, and extract significant value from it.

Governed by intergovernmental agreements, the ISS functions on in-kind contributions from NASA’s partner agencies (in Europe, Japan, Canada, and Russia), in exchange for utilizing the station’s resources. This is often referred to as a “barter system” in which goods and services are exchanged without direct monetary transfer, sidestepping the political complexities of commercial transactions.

Despite the perception of “barter,” the ISS operates as a monetary system. Every kilogram of mass to orbit, every kilowatt-hour of power, every hour of crew time is meticulously valued and accounted for. These are the fundamental commodities of a space economy.

The exchange of an astronaut’s research time for a laboratory’s power supply is, in effect, a transaction. The current system is a ledger-based economy where the transactions are recorded, but the units of value lack transferability and liquidity outside of the ISS framework.

In building a machine of extraordinary productive capacity, the scientific and engineering communities inadvertently created a closed monetary system. By not categorizing the ISS as a monetizable enterprise, an immense amount of enterprise value remains latent and inaccessible to the broader market.

The value of the ISS isn’t just the construction costs — its value is the intellectual property and data generated, the technological advancements and infrastructure, the human capital and expertise, and the developing market for future low-Earth orbit (LEO) activities. Yet under the current barter model, none of this can be priced, traded, or reinvested. It sits locked inside a closed system that was never designed to produce economic returns.

The next great leap in space will be made through business model innovation. The next great challenge is to build the financial bridge that connects the nascent, commodities-based economic model of the ISS into with the modern, trust-based global financial system. This bridge will be a transparent, market-based mechanism to convert the inherent value of orbital commodities–— power, crew time, volume, and mass— into fungible, tradable assets.

The beauty of this approach is that it avoids politically complex bilateral funding discussions and instead lets the market determine the most efficient use of resources. Surpluses of resources can be monetized instantly, and new startups with innovative payloads can operate without years of government red tape. Essentially, money needs to flow through the space economy the same way it flows through every other functioning market on Earth.

As SpaceX prepares its IPO and builds the physical rails to explore our next frontiers, and as NASA prepares to deorbit the ISS, we have a rare chance to design the market infrastructure for humanity’s next expansion. Without that market infrastructure, the space economy starts over from zero. The end of the ISS must not be a burial of assets — it needs to be a successful capital raise for the future of humanity off planet — a feat that no single country, company, or individual can achieve alone.

The opinions expressed in Fortune.com commentary pieces are solely the views of their authors and do not necessarily reflect the opinions and beliefs of Fortune.