Following the release of the 2018 budget, the space agency has ordered an orderly closeout for the Asteroid Redirect program.

NASA's Asteroid Redirect Mission would have retrieved a boulder from the surface of an asteroid. NASA

After years of study, NASA announced recently that its plan to retrieve an asteroid and place it in lunar orbit, known as the Asteroid Redirect Mission (ARM), will be shut down due to lack of congressional support in the proposed FY2018 budget. The NASA ARM program director Michele Gates made the announcement on June 13th, during the recent meeting of the Small Bodies Assessment Group held at the Goddard Space Flight Center in Greenbelt, Maryland. The focus will now turn shutting down the program while salvaging key technologies and lessons learned for other possible future applications.

The agency remains committed to the next human missions to deep space, but we will not pursue the Asteroid Redirect Mission (ARM) with the Fiscal Year 2018 budget proposal, says Kathryn Hambleton (NASA). The ARM team is in the process of documenting its activities to ensure key knowledge from the mission concept is archived as part of an orderly closeout.

This artist's concept shows an astronaut examining the returned boulder while in lunar orbit. NASA

ARM was an ambitious plan from the start. First proposed in 2013, the project called for an automated rendezvous and capture of a small near-Earth asteroid, which would then be placed in orbit around the Moon. Astronauts would then rendezvous with the asteroid in lunar orbit, study the asteroid, and collect and return samples to Earth. NASA ARM would have relied on the new Orion crewed capsule and the new Space Launch System (SLS) heavy lift rocket, both still under development.

Politically, the mission had detractors from the start, and it failed to find support in Congress, even though the plan was often touted as a stepping stone between leaving low-Earth orbit and heading to Mars in the 2030s. From an engineering perspective, the plan plan was complex, requiring an automated spacecraft to retrieve an SUV-sized boulder from a larger asteroid moving slowly relative to Earth's orbital motion, a scenario that significantly limited the potential targets.

Our best look at Bennu, one of the asteroid candidates for the boulder retrieval concept of ARM. The image at right shows radar reflectivity as measured by Arecibo, with the radar beam shining from the top. At right is a reconstruction of Bennu's shape using those data. NASA / Arecibo

But even as the ARM mission closes out, research and development will still continue in some key areas. The solar electric propulsion system, initially envisioned to fly on the robotic segment of ARM, is still being developed for future deep-space use. And the search for near-Earth asteroids involving observatories worldwide will go on.

While our long-term Mars architecture is still in development, Hambleton says, we've recently unveiled a concept using SLS and Orion to build a deep space gateway and transport in cis-lunar space to help us prepare for human deep space missions, including Mars.

Changes expected from the president's budget request for NASA. AAAS

The end of NASA ARM is also part of a larger picture: a time of transition amid the new presidential administration. NASA overall actually makes out pretty well in the proposed FY2018 budget: $19.1 billion dollars, a 3% drop from the $19.7 billion budget of FY17, though still slightly above where NASA funding levels have stalled for the past decade. Planetary sciences was the big winner in the FY18 NASA budget, getting a proposed $1.9 billion dollars, the division's highest annual funding to date. This will support the Mars 2020 rover and the Mars InSight lander, as well as the Europa Clipper and Lucy and Psyche asteroid missions planned for the 2020s.

A lion's share of NASA's proposed budget will go towards continued support of the International Space Station, the James Webb Space Telescope (set to launch in late 2018), and development of the Orion capsule and the SLS, though the latter face significant cuts. The first flight of Orion aboard the SLS is slated for 2019 and will carry an uncrewed capsule around the Moon and back. NASA studied the idea of putting a crew on the first Orion/SLS flight but nixed the idea last month.

Along with NASA ARM, NASA's Earth sciences division will take a hit under the proposed budget, losing $170 million dollars for a nearly 9% drop from FY17 to FY18. This puts several crucial Earth observing missions, including the Orbiting Carbon Observatory (OCO-3) and the Deep Space Climate Observatory (DSCOVR), in jeopardy. However, 18 Earth-observing missions will remain in orbit, according to NASA acting administrator Robert Lightfoot.

NASA's Office of Education also faces closure with this budget, with just $37 million set aside for transitional and closing costs.

However, while some changes appear to be set, such as the ARM close-out, it's important to remember that the president's budget request often changes before it becomes signed into law later in the year. The Planetary Society offers their take on NASA's new budget here. To learn how the NASA budget comes about, watch this explanation from The Planetary Society's Casey Dreier:

When it comes to NASA funding, it's an uncertain time of crisis and opportunity. As ever, the phrase no bucks, no Buck Rogers applies. We're also now farther away from the end of the U.S. Space Shuttle program in 2011 than the first shuttle flight in 1981 was from the end of Apollo in 1975.

Perhaps, the lessons from NASA ARM will get paid forward, as U.S. astronauts once again venture out of low-Earth orbit in the next decade.

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NASA Closes Out Its Asteroid Redirect Mission - Sky & Telescope