NASA’s ambitious plan to put boots on the Moon in 2024 is looking increasingly costly — and increasingly unlikely — if the current cost overruns and delays are any indication, according to a report by the agency’s Office of the Inspector General.

“NASA’s continued struggle with managing SLS Program costs and schedule has the potential to impact the Agency’s ambitious goals for the Artemis program,” reads the report issued yesterday. “Each of the major element contracts for developing and building the SLS for Artemis I—Stages, ICPS, Boosters, RS-25 Adaptation, and RS-25 Restart—have experienced numerous technical challenges, performance issues, and requirement changes that have resulted in $2 billion of cost overruns and increases and at least 2 years of schedule delays.”

That doesn’t mean that the 2024 date has slipped to 2026, of course — the delays are in the creation of the first, test version of the Space Launch System, the next-generation heavy-lift launch vehicle NASA intends to use for the crewed Artemis missions. That first launch is currently estimated to take place sometime in spring of 2021 — more than two years after the original estimate.

To put those delays in perspective, the SLS program really started back in 2010, with the design stage concluding in 2014 and contracts for testing and manufacturing being awarded after that. Dates as early as 2016 were floated for SLS readiness, but NASA eventually officially committed to late 2018. But that has slipped several times, most recently in January, when NASA said that launch in November of this year was no longer tenable.

What’s more, these extensions and difficulties (some at NASA, some at contractors and subcontractors) have complicated finances and caused the program to blow past its original budget. Part of this is simply in how it’s reported, but it also means that what has been accomplished has cost more than expected.

As the report states: “Overall, by the end of fiscal year 2020, NASA will have spent more than $17 billion on the SLS Program—including almost $6 billion not tracked or reported as part of the ABC.” That’s the Agency Baseline Commitment, essentially what NASA told Congress it would do in order to get this funding secured.

It should surprise no one that a major endeavor like accelerating a Moon landing program is more difficult and expensive than first suspected. And ultimately what matters for Artemis is that the U.S. return to the Moon — “to stay,” as Administrator Jim Bridenstine is fond of saying — safely and in good time. The 2024 goal is an arbitrary one and no engineer or astronaut is going to rush the project in order to satisfy a political agenda — not when lives are at stake.

The Office of the Inspector General makes a few suggestions as to how to better track spending and keep NASA and its contractors accountable for time and spending. But the repeated warnings of delays seem to indicate, if never to actually state, that the goal of getting to the Moon in 2024 is only a few months of delays away from being no longer possible.