WASHINGTON — NASA has masked the true cost of the Space Launch System and Orion crew capsule by neglecting to say what these deep-space systems will cost to build and operate over the decades the agency plans to use them, according to a report from the U.S. Government Accountability Office.

NASA so far has put only two SLS missions on the manifest: a late-2017 test launch of an unmanned Orion into lunar space followed by a repeat of the mission in 2021 with crew onboard. NASA officials told GAO auditors it expects to have spent at least $22 billion on SLS and Orion through 2021, an estimate that does not include the cost of building the SLS launcher for the second mission, the government watchdog wrote in a May 9 report, “Actions Needed to Improve Transparency and Assess Long-Term Affordability of Human Exploration Programs.”

The report was done at the request of Sen. Tom Coburn (R-Okla.), the ranking member of the Senate Homeland Security and Government Affairs Committee.

NASA says it is standard procedure to avoid releasing cost estimates for a second vehicle before it has finalized a cost estimate for the first vehicle.

Moreover, NASA provided no cost estimate for the more powerful SLS rocket NASA would need to mount a crewed Mars expedition the Obama administration envisions happening in the 2030s. According to NASA’s early plans, such a mission would entail multiple SLS-Orion launches.

The cost estimates NASA has offered so far “provide no information about the longer-term, life cycle costs of developing, manufacturing, and operating the launch vehicle, crew capsule, and ground systems” the agency has identified as crucial to the eventual Mars mission, the GAO wrote in its report. NASA’s limited cost estimate “does not provide the transparency necessary to assess long-term affordability and will hamper oversight by those tasked with assessing whether the agency is progressing in a cost-effective and affordable manner,” the GAO wrote.

The GAO recommended NASA put together a cost estimate for the SLS needed for the 2021 mission, and for SLS upgrades required for future missions, and include these target costs in its annual budget request to Congress. These estimates should “establish separate cost and schedule baselines for each additional [SLS] capability that encompass all life cycle costs, to include operations and sustainment.”

NASA has not released comprehensive, long-term cost estimates for SLS and Orion. The reason is to avoid giving Congress sticker shock, said William Gerstenmaier, NASA’s associate administrator for human exploration and operations.

“If we laid out a path directly to Mars and we laid out all the vehicles and all the testing and all the work to get there, then you end up with a fairly long period of time with a lot of funding that goes into that activity that says this program is something maybe we don’t want to go do,” Gerstenmaier said in November during a panel discussion with SLS and Orion prime contractors at the Newseum in Washington.

Congress ordered NASA to build SLS and Orion in the NASA Authorization Act of 2010, which U.S. President Barack Obama signed that year despite his administration’s preference to focus NASA’s human spaceflight dollars on public-private partnerships and development of a liquid-fueled rocket engine capable of producing 1 million pounds of thrust.

NASA has since folded SLS and Orion into a long-term plan to send humans to Mars in the 2030s. The details of NASA’s plans are still very rough, but the agency has said publicly that a crewed expedition to Mars would require multiple launches of a more powerful SLS than the 70-metric-ton capable versions set to fly in 2017 and 2021.

The first two SLS vehicles will comprise a main stage consisting of four modified space shuttle main engines; a pair of side-mounted, five-segment solid rocket motors; and an upper stage adapted from the one used on the Boeing-designed Delta 4, one of two rockets currently produced by United Launch Alliance.

NASA’s plans to boost SLS performance for future missions do not currently involve the J-2X engine the agency shelved in 2013 after a $1.5 billion, eight-year development effort.

Similarly, NASA has backed off of a plan to upgrade SLS with a pair of competitively selected strap-on boosters to replace the ATK-provided solids that will boost the 2017 and 2021 missions off the pad, Gerstenmaier told SpaceNews May 8. The scuttled competition had been scheduled for 2015.

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