WASHINGTON — Former NASA Deputy Administrator Lori Garver, speaking Jan. 2 on National Public Radio’s “The Diane Rehm Show,” made some of her most critical comments since stepping down in September about two key NASA programs: the Space Launch System and Mars 2020 rover.

Early in the show, Garver hinted that NASA was not spending its budget as effectively as it could after Rehm suggested NASA’s core problem was that it did not have a big enough budget. “I’m not sure it is, actually,” she said. “I believe that NASA and their $17 billion has an incredibly exciting and important space program. Of course, we could do even more with our $17 billion, and I think if we did that we would engender that support from the public and their elected leadership.”

Later in the show, Rehm asked Garver what NASA programs she felt should be cut. “To me, I think those particular programs that are built on previous technology,” she said. “Right now, we’re building a huge rocket called the Space Launch System, the SLS. It was something that Congress dictated to NASA that it had to do, with the Orion spacecraft. It is a holdover from Constellation, which the Obama administration tried to cancel, and it’s $3 billion a year of NASA’s $17 billion. Is that how you would be investing in the space program? Where is it going to go? When will it even fly?” The $3 billion figure she cited is actually the approximate combined value of the SLS and Orion budgets, not SLS alone.

Another guest, Scott Pace of George Washington University’s Space Policy Institute in Washington, defended SLS. “If we’re going to be going to Mars eventually, if someone wants to do a human mission to Mars, you basically do need a heavy-lift vehicle,” he said. Constellation, he argued, would have developed its Ares 5 heavy-lift rocket in a more logical manner by starting with the smaller Ares 1.

Garver was not convinced. “The rocket is so similar, and it’s built off of 1970s technology. The very engines we’re going to use are space shuttle engines that were developed in the 1970s. Would you really go to Mars with technology that’s 50 years old? That’s not what innovation and our space exploration program should be all about.”

She also was critical of NASA plans to send a rover to Mars in 2020 closely modeled on the Curiosity rover. “I would not redo the Curiosity mission,” she said. “I would invest that planetary science mission in doing something new like Europa, or going to Mars in a more creative and innovative way where we can again drive technology.”

That built upon comments she made earlier in the show. “If you’re a Mars scientist, you want to keep having NASA fund your Mars missions and keep redoing, for instance, what we just did with Curiosity is now planned again for 2020, instead of what you could be doing, driving in a new direction on Europa,” she said.

While NASA’s decision just more than a year ago to proceed with a 2020 Mars rover met with complaints from some parts of the planetary science community, who felt NASA was overemphasizing Mars over other parts of the solar system, it is largely consistent with the decadal survey the community produced in 2011. That report identified as the top priority large, or “flagship,” mission a Mars rover that would cache samples for later return to Earth. A science definition team report published in July did indeed recommend that the rover include the ability to cache samples for a future, as yet undefined, sample-return mission.