NASA's next rover may be at risk of missing its July 2020 launch date, adding millions to the project's cost, if engineers don't step up development of several key technologies, an audit of the program released on Monday showed.
Of particular concern is the system to collect and store soil and rock samples for eventual return to Earth.
An audit by the agency's Office of Inspector General (OIG) found that five of the project's seven key technologies were lagging. The report also said 90 percent of the engineering drawings that were expected to be finished by next month's critical design review "do not appear to be on track."
In an email to Seeker, NASA said it was working to respond to the OIG's recommendations.
The so-called "Mars 2020" rover is a $2.4 billion follow-on mission to NASA's Mars Science Lab Curiosity expedition, which began with the spacecraft's daring sky-crane descent to Gale Crater in August 2012.
Curiosity is exploring a mile-high mound of sediment known as Mount Sharp, which rises from the crater's floor. It quickly accomplished the primary goal of its mission to learn if the planet most like Earth in the solar system ever had the chemical ingredients and environments to support life.
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With analysis of its first sample, Curiosity found that Earth microbes would have found a suitable home on ancient Mars. The ongoing mission is intended to characterize other habitable niches for life and figure out how best any signs of potential life could have been preserved.
Mars 2020, whose landing site has not yet been selected, will pick up the search for habitable environments and actually attempt to find evidence of past life.
In addition to seven science instruments, Mars 2020 will be outfitted with a system to collect and cache samples that a future rover or human explorers can retrieve so they can be returned to Earth for analysis.
"The immaturity of critical technologies related to the Sampling System is concerning for three reasons," the OIG report said.
"First, managers told us the Sampling System is the most complex new development component of the Project. Accordingly, solutions to address associated risks are likely to be complicated and time consuming.
"Second, other risks being tracked by the Project related to the Sampling System include potential delays in development of the actuators, additional restrictions on assembly and tests due to new or modified planetary protection and contamination control requirements, and a redesign of hardware necessitated by limitations in performance or increases in mass or volume of the new actuators.
"Third, because the Sampling System is on the Project's critical path, delays are likely to eat into the Project's schedule reserve and, in the worst case scenario, could delay launch," the report said.
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Investigators said that as of December 2016, the sampling system may not be ready for integration and testing in May 2019 as planned.
"Late deliveries at the Assembly, Test, and Launch Operations phase could mean some tests are performed with surrogate rather than flight hardware or some tests may need to be repeated or not performed at all. Although we are unable to determine the extent to which immature critical technologies contribute to this risk, ultimately the Sampling System is a mission critical component and Mars 2020 may not launch without it," the report said.
Missing the launch window would result in "significant" additional costs to store the spacecraft, replace degraded components and maintain the workforce, among other expenses.
Curiosity, for example, ended up costing an extra $834 million, when its launch was delayed 26 months due to technical issues.
A better picture of Mars 2020's status will come after the project's three-day Critical Design Review scheduled to begin on Feb. 28.
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