WFIRST was the No. 1 rated large-scale mission in the 2010 decadal survey for astrophysics. Credit: NASA illustration

WASHINGTON — The U.S. House of Representatives on June 3 approved a spending bill that would boost NASA’s astrophysics budget, but strings attached to the measure could actually force the division to make $21.3 million in unplanned cuts, a senior NASA official said.

Under the 2016 Commerce, Justice, Science, and Related Agencies Appropriations Act (H.R. 2578) just passed by the full House, NASA’s Astrophysics Division would get some $735.6 million of the $18.5 billion appropriators saw fit to include for NASA.

While that’s nearly $9 million more than NASA’s 2015 astrophysics budget and $26.5 million more than the division’s proposed 2016 budget, the same bill calls for NASA to more than triple what it is planning to spend next year on continued formulation of the Wide Field Infrared Survey Telescope (WFIRST), the next big astrophysics mission after the nearly $9 billion James Webb Space Telescope.

NASA requested $14 million for WFIRST for 2015 only to see Congress increase the program’s budget to $50 million. House appropriators are looking to do the same again this year, adding $35.8 million to NASA’s identical $14 million request.

House appropriators likewise rejected NASA’s proposal to roll back spending on the Astrophysics Division’s educational outreach. The bill before the House includes $32 million for such efforts — $12 million more than NASA requested.

NASA Astrophysics Director Paul Hertz. Credit: NASA

If H.R. 2578 were to become law as written, NASA would be forced “to find $21 million in reductions in everything that is not WFIRST or education,” Paul Hertz, NASA’s astrophysics director, told the National Science Foundation’s Astronomy and Astrophysics Advisory Committee during a June 1 teleconference.

The House’s WFIRST plus-up was bundled with a directive to ramp up development work on a coronagraph: An instrument WFIRST could use to detect faraway exoplanets. John Grunsfeld, NASA’s associate administrator for science and Hertz’s boss, has pushed hard to include the coronagraph on WFIRST.

Astronomers declared WFIRST their top priority after JWST in the 2010 decadal survey “New Worlds, New Horizons.” Hertz said the telescope, notionally to be built around a Hubble-sized spy satellite donated to NASA by the National Reconnaissance Office in 2012, would not become an official NASA mission until at least 2017. Launch would not happen until 2024 or 2025, said Hertz.

Only by 2017, Hertz said, will JWST spending have ramped down enough to steer sufficient astrophysics funding into another big project. JWST cost NASA about $660 million in 2014, which was projected to be the peak spending year. Spending has declined since, with the White House requesting $620 million in 2016 — a figure House appropriators matched in their latest bill. JWST is scheduled to launch in 2018.

A budget chart Paul Hertz, director of NASA's Astrophysics Division, briefed to the interagency Astronomy and Astrophysics Advisory Committee June 1. Credit: SpaceNews screen capture
Hertz broke down the effects of the House Appropriations Committee’s 2016 NASA spending bill in a chart he briefed during a June 1 teleconference with other government astronomers. Credit: SpaceNews screen capture.
Hertz broke down the effects of the House Appropriations Committee’s 2016 NASA spending bill in a chart he briefed during a June 1 teleconference with other government astronomers. Credit: SpaceNews screen capture.

Despite Grunsfeld’s enthusiasm for a WFIRST coronagraph, NASA has not officially decided whether to include one on the mission. In a February report, the WFIRST Science Definition Team, based at the agency’s Goddard Space Flight Center in Greenbelt, Maryland, finalized a recommendation that Hertz accelerate technology development work on the coronagraph so NASA can develop a credible cost estimate for including the instrument on WFIRST.

Astronomers at the National Academy of Sciences, while supportive of a WFIRST coronagraph, have already lodged official concerns about the budgetary risks of shoehorning one onto the mission.

Meanwhile, Hertz did not speculate about which astrophysics programs would be cut if H.R. 2578 becomes law.

Dan Leone is a SpaceNews staff writer, covering NASA, NOAA and a growing number of entrepreneurial space companies. He earned a bachelor’s degree in public communications from the American University in Washington.