The budget coming Monday from the Obama administration will send the NASA division that launches rovers to Mars and probes to Jupiter crashing back to Earth.

Scientists briefed on the proposed budget said that the president’s plan drops funding for planetary science at NASA from $1.5 billion this year to $1.2 billion next year, with further cuts continuing through 2017.

It would eat at NASA’s Mars exploration program, which, after two high-profile failures in 1999, has successfully sent three probes into Martian orbit and landed three more on the planet’s surface.

“We’re doing all this great science and taking the public along with us,” said Jim Bell, an Arizona State University scientist and president of the Planetary Society who works on NASA’s Mars rover Opportunity. “Pulling the rug out from under it is going to be really devastating.”

If approved, the president’s budget will sever NASA’s partnership with the European Space Agency to send probes to Mars in 2016 and 2018. Agreed upon in 2009, NASA was to pay $1.4 billion, and the Europeans $1.2 billion, for the two missions.

In an e-mail, NASA spokesman David Weaver wrote, “Consistent with the tough choices being made across the Federal government . . . NASA is reassessing its current Mars exploration initiatives to maximize what can be achieved scientifically, technologically and in support of our future human missions.”

A congressional champion of space exploration said that the budget slashing “absolutely will not fly” with the House committee that oversees NASA.

“You don’t cut spending for critical scientific research endeavors that have immeasurable benefit to the nation and inspire the human spirit of exploration we all have,” Rep. John Abney Culberson (R-Tex.) said.

Last fall, NASA handed out $46 million to contractors to begin building instruments for the 2016 mission.

But earlier this week, Alvaro Gimenez, top scientist at the European agency, told the BBC that NASA’s continued participation in the partnership was “highly unlikely.”

“The impact of the cuts . . . will be to immediately terminate the Mars deal with the Europeans,” said G. Scott Hubbard, a Stanford University and former NASA planetary scientist who revived the agency’s Mars exploration program after the 1999 failures. “It’s a scientific tragedy and a national embarrassment.”

The 2016 mission, called the Trace Gas Orbiter, was to sniff the Martian atmosphere for methane, which could signal the existence of microbes on the surface. The 2018 mission was to land a rover to gather rocks and soil for eventual return to Earth.

An official familiar with deliberations at NASA said the agency is still hoping to launch a robotic Mars mission in 2018, although the goals and hardware would probably differ from those of the joint European project.

With austere budgets expected across the federal government, NASA is finding itself squeezed. Last year, Congress ordered the agency to build a giant new rocket and a deep-space crew capsule. Congress also told the agency to finish the overbudgeted James Webb Space Telescope, now expected to launch no earlier than 2018.

The executive branch’s budget request, unveiled every February, is used by federal agencies to set spending priorities. Details are often decided by officials in the White House’s Office of Management and Budget.

On Wednesday, planetary scientists accused the OMB of ignoring advice given to NASA by its scientific advisers. In May, planetary scientists told the agency they favored two big projects: the Mars missions, or, if those proved too expensive, a probe to explore Europa, an intriguing moon of Jupiter with an ice-covered ocean and, within it, conditions possibly favorable for life.

“They don’t seem to be interested in finding life in the universe or letting the experts manage their own program,” Hubbard said of the OMB. “Low-level workers have substituted their judgment for 1,700 scientists and the National Academy of Sciences.”

Culberson said the House committee would continue to push for the Europa mission, which Congress directed the agency to study this year.