Concept art of InSight Lander drilling beneath Mars' surface. Credit: NASA

GREENBELT, Md. — A Mars mission that had to cancel plans to launch this month because of an instrument problem will instead fly in 2018, although the additional cost to NASA will not be known for several months.

NASA announced March 9 that the launch of the InSight Mars lander has been rescheduled for May 2018, the next available launch window. A launch then would set up a landing on Mars in November 2018.

InSight was scheduled to launch this month on a United Launch Alliance Atlas 5 from Vandenberg Air Force Base in California. However, in December NASA cancelled the launch after concluding that a seismometer, one of the spacecraft’s key instruments, would not be ready in time after experiencing a series of leaks in its vacuum-sealed components.

NASA has accepted a plan to redesign the faulty instrument, called the Seismic Experiment for Interior Structure and provided by the French space agency CNES. The Jet Propulsion Laboratory will design, build and test a new vacuum enclosure for the instrument, while CNES will be responsible for instrument level integration and testing.

The NASA announcement did not disclose the cost of the two-year delay, noting that a final value won’t be known until August, after NASA makes arrangements for the rescheduled launch with ULA. At a March 2 meeting of the Mars Exploration Program Analysis Group, Bruce Banerdt, principal investigator for InSight, estimated the cost to be “on the order” of $150 million.

In an interview during the Goddard Memorial Symposium here March 9, John Grunsfeld, NASA associate administrator for science, suggested that good performance on other missions could provide financial reserves to diminish the fiscal effects of the delay. “The actual impact is probably less than half of that $140–150 million,” he said.

The Discovery program of low-cost planetary science missions, which includes InSight, would likely absorb those remaining costs. That would not rule out the selection of two Discovery missions later this year from among five finalists, Grunsfeld said. However, he added that if NASA did select two, the start of the second mission could be delayed by six months to a year to cover those costs.

Work to repair the faulty seismometer does not affect the rest of the InSight spacecraft, which is based on the Phoenix mission that landed on Mars in 2008. Stu Spath, spacecraft program manager at Lockheed Martin, said March 9 his team is preparing to put the lander into storage at the company’s facilities near Denver.

InSight is designed to study the interior of Mars as part of efforts to better understand the formation of terrestrial planets. Besides the seismometer, its other key instrument is a probe to measure heat flow beneath the planet’s surface.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...