An engineering model of NASA's next-generation manned spacecraft Orion, is pictured Monday, March 6, 2017, at Yuma International Airport in Yuma, Ariz. (Matt Harding/AP)

President Trump’s first federal budget seems to make good on his campaign promises to shift NASA’s focus away from Earth and toward space. But it doesn’t reveal where he thinks the agency should be headed — to Mars, the moon or elsewhere.

Overall, Trump would shrink funding for NASA slightly, to $19.1 billion from about $19.3 billion, according to a blueprint of the president’s budget requests for 2018.

The largest portion of funds would go to the agency’s human exploration division, with $3.7 billion for the Orion crew vehicle and Space Launch System (SLS) jumbo rocket, spacecraft that NASA says will one day get humans to Mars. The outlined budget also instructs NASA to “investigate approaches for reducing the costs of exploration missions to enable a more expansive exploration program.”

It is not clear what such an expanded program might entail. Unlike last year’s presidential budget, Trump’s outline makes no mention of the journey to Mars, NASA’s target throughout the Obama administration. Trump has recently hinted that he is interested in returning astronauts to the moon, perhaps as soon as the first SLS test flight in 2018.

The outlined budget continues to fund two major planetary missions: the Mars 2020 Rover that would explore the Red Planet and the Europa Clipper, a probe that is to fly past the Jupiter moon in search of life that might dwell in its subsurface ocean. A Europa lander and a mission that would have sent astronauts to study an asteroid in lunar orbit did not make the cut.

The budget document fits with Trump’s interest in ceding parts of NASA’s mission, such as International Space Station operations and maintenance of satellites, to the private space industry.

The total cut to the Earth-science budget is $102 million, or 5 percent of the program’s annual budget, and it almost exclusively targets missions aimed at understanding climate change — the ocean monitoring program PACE; the Orbiting Carbon ­Observatory-3; the Deep Space Climate Observatory; and the CLARREO Pathfinder, which measures heat in Earth’s atmosphere.

Also on the chopping block: the entire NASA Education office, which runs camps and enrichment programs, provides internships and scholarships for young scientists, and oversees efforts to support women and underrepresented minorities in science, technology, engineering and math, or STEM, fields.

What's getting cut in Trump's budget