WASHINGTON — NASA’s astrophysics division will cut several million dollars of research funds this year to partially cover a broader funding shortfall created by congressionally mandated allocations to other division programs.

Paul Hertz, director of NASA’s astrophysics division, told a meeting of the National Science Foundation’s Astronomy and Astrophysics Advisory Committee June 6 that a $3 million cut in research and analysis (R&A) funds was the one “real impact” in $36 million in savings he had to find within the astrophysics program for fiscal year 2016.

Those savings, incorporated into NASA’s operating plan for 2016, were required to account for a difference between NASA’s request for astrophysics programs and what the agency received in the final appropriations bill passed by Congress in December 2015. While the astrophysics program overall received a $42 million increase, Congress increased funding for the Wide Field Infrared Survey Telescope (WFIRST) by more than $75 million, requiring offsets in other programs.

Hertz said most of the cuts would have little effect on ongoing astrophysics programs. The agency found much of the needed funding by freeing up unused project reserves in programs, or rephasing them to later years. It also pushed back development of future Explorer-class missions by two months.

The cut in R&A funding, while small, is significant, he said. “The one place where I will say there was a real impact to the community was the $3 million we had to remove from R&A,” he said.

The R&A program provides grants to astronomers to carry out research in various aspects of astrophysics. “There will be fewer selections [of proposals] this year and next year to accommodate that $3 million reduction,” he said. That cut, he added, accounts for about three percent of the overall R&A budget.

Hertz said it was too soon to determine how the cut in R&A funding would affect specific research programs, since proposals are still being reviewed. He said the impact would be reduced by adjusting funds for those who have awards and have not spent their money as fast as planned.

The cut in research funds, he said, was the best they could do to limit the effect of the overall shortfall. “It’s very difficult to accommodate these reductions when they don’t become real until halfway through this year,” he said. “One of the very few things that you can reduce are the things that you haven’t selected yet.”

Hertz also warned that similar cuts may be required in 2017. While appropriations bills in the House and Senate provide modest increases for the overall astrophysics program over the administration’s request, they also include larger increases for specific programs. The Senate’s bill, for example, increases the budget for WFIRST by $30 million, while the House sets aside $10 million in technology development for a “starshade” that could be used to help detect extrasolar planets but was not specifically requested by NASA.

In the current version of the Senate bill, NASA would have to make $27.5 million in cuts in other astrophysics programs, and the House bill would require $12 million in cuts. Hertz, though, emphasized an eventual compromise version of the bill might mitigate those cuts depending on the final funding level they accept.

That final bill, he added, is not expected until after the November general election. “None of us think that we’ll get a budget before the election,” he said.

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...