Nasa has canceled its only robotic vehicle under development to explore the surface of the moon.

Members of the agency’s Resource Prospector mission were told to close down the project by late May.

While Nasa has not given details on why it canceled the mission, one of the team’s planetary scientists speculated it was likely budget related.

The decision comes just months after US President Donald Trump ordered Nasa to return astronauts to the moon for the first time since 1972.

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Nasa has canceled the only robotic vehicle under development to explore the surface of the moon. Pictured is a prototype of the rover, dubbed Resource Prospector, searching for a buried sample tube at the Johnson Space Center rock yard in August 2015

Scientists working on the Resource Prospector (RP) mission, a robotic rover that had been in development for about a decade to explore a polar region of the moon, expressed astonishment at the verdict.

‘We now understand RP was canceled on 23 April 2018 and the project has been asked to close down by the end of May,’ said a letter dated April 26 by the Lunar Exploration Analysis Group, addressed to Nasa chief Jim Bridenstine and posted on the website NASAWatch.com.

‘This action is viewed with both incredulity and dismay by our community,’ particularly because Trump’s space policy “directs Nasa to go to the lunar surface”‘, the letter said.

The robotic rover was meant to be the world’s only vehicle aimed at exploring the polar region of the moon.

It was expected to undergo a design review next year ahead of launching in 2022.

It would have been the first US lunar lander since Apollo 17 in 1972, and the first ever US robotic rover on the surface of the moon.

Members the Resource Prospector mission, which was set to be first mining expedition on another world, were told to close down the project. The robot was set to take soil samples at the lunar poles. Pictured is a prototype taking samples during testing in August 2015

RP was intended to be the first mission to mine the surface of the moon, in search of volatile compounds like hydrogen, oxygen, and water.

According to Dr Phil Metzger, a planetary physicist at the University of Central Florida who is part of the science team for Resource Prospector, the mission was likely canceled when it transferred to a different Nasa directorate.

The mission was initially funded as part of the agency’s human exploration arm but was later moved to the directorate that funds science missions.

Because the rover is taking soil samples rather than doing ‘straight science’, it does not fit under science directorate’s priorities or budget, Dr Metzger said.

WHAT WAS NASA’S RESOURCE PROSPECTOR ROVER AND WHY WAS IT CANCELLED?

Nasa’s Resource Prospector was a robotic rover that was intended to be the first mission to mine the surface of the moon.

The robot, developed by Nasa over the course of a decade, was designed to search for volatile compounds like hydrogen, oxygen, and water.

It was expected to launch in 2022 and form part of US President Donald Trump’s December 2017 directive ordering Nasa to return astronauts to the moon for the first time since 1972.

Nasa’s Resource Prospector (artist’s impression) was a robotic rover that was intended to be the first mission to mine the surface of the moon

On April 23 2018, RP was canceled and all scientists involved in the project were asked to close down operations by the end of May.

Officials from Nasa declined to elaborate on the cancellation.

In a statement posted online, the agency said some of the instruments aboard RP would be flown on future missions.

According to Dr Phil Metzger, a planetary physicist at the University of Central Florida who is part of the science team for Resource Prospector, the mission was likely canceled when it transferred to a different Nasa directorate.

On April 23 2018, RP (artist’s impression) was canceled and all scientists involved in the project were asked to close down operations by the end of May

The mission was initially funded as part of the agency’s human exploration arm but was later moved to the directorate that funds science missions.

Because the rover is taking soil samples rather than doing ‘straight science’, it does not fit under science directorate’s priorities or budget, Dr Metzger said.

Though he could only speculate, the physicist said this is likely the reason RP was canceled.

He told the Verge: ‘I don’t really know what the motive was, but I’m guessing it was probably budget related.’He told the Verge: ‘I don’t really know what the motive was, but I’m guessing it was probably budget related.’

Dana Hurley, a planetary scientist at the Johns Hopkins Applied Physics Laboratory, said the robot was a vital part of Nasa’s plans to put astronauts on the moon.

‘If we want to go back to the moon and really work on the moon and make it a place that we can set up research stations and study processes that are occurring on the moon … all these things are really enabled by being able to use resources on the moon for making fuel, propellant, life support, that sort of thing,’ he said in an interview on Friday.

RP was intended to be the first mission to mine the surface of the moon (artist’s impression), in search of volatile compounds like hydrogen, oxygen and water. Nasa said in a statement that some of the instruments aboard RP would be flown on future missions

In a letter to newly confirmed Nasa administrator Jim Bridenstine, the Lunar Exploration Analysis Group – which conducts analyses for Nasa and other space agencies – called for the mission to be reinstated and scheduled to launch in 2022.

‘This action is viewed with both incredulity and dismay by our community,’ the group wrote.

Officials from Nasa declined to elaborate on the cancellation.

Nasa said in a statement posted Friday that some of the instruments aboard RP would be flown on future missions.

‘Nasa is developing an exploration strategy to meet the agency’s expanded lunar exploration goals,’ said the statement.

‘Consistent with this strategy, Nasa is planning a series of progressive robotic missions to the lunar surface.’

In December 2017, US President Donald Trump formally directed Nasa to focus its efforts on returning people to the moon as a foundation for an eventual mission to Mars

It did not specifically refer to any plans to cancel RP, but said the space agency is seeking ‘to evolve progressively larger landers leading to an eventual human lander capability,’ as part of a broader strategy to return people to the moon for long-term exploration.

‘As part of this expanded campaign, selected instruments from Resource Prospector will be landed and flown on the moon,’ it said.

Bridenstine, who was confirmed this week as the new head of Nasa, insisted on Twitter that the US space agency is ‘committed to lunar exploration.’

‘Resource Prospector instruments will go forward in an expanded lunar surface campaign. More landers. More science. More exploration. More prospectors. More commercial partners,’ he wrote.

In December 2017, Trump formally directed Nasa to focus its efforts on returning people to the moon as a foundation for an eventual mission to Mars.

The goal of the new moon missions would include ‘long-term exploration and use’ of its surface.

The last time US astronauts visited the Moon was the Apollo 17 mission of December 1972. This image shows astronaut Harrison H. Schmitt seated in the Lunar Roving Vehicle on the surface of the moon on December 13, 1972

‘This time we will not only plant our flag and leave our footprint,’ Trump said at the White House as he signed the new space policy directive.

‘We will establish a foundation for an eventual mission to Mars and perhaps someday to many worlds beyond.’

Under the directive, the government is also expected to work closely with other nations and private industry.

The last time US astronauts visited the Moon was the Apollo 17 mission of December 1972.