What is the goal
for the Asteroid
Redirect Mission?
Through the Asteroid Redirect Mission, NASA will
identify, capture and redirect an asteroid to a stable orbit around the moon,
which astronauts will explore in the 2020s, returning with samples. The mission
is an important early step as we learn to be more independent of Earth for
humans to explore Mars. It will be an unprecedented technological feat
that will lead to new scientific discoveries and technological capabilities,
while helping us learn to protect our home planet. The overall objectives of
the Asteroid Redirect Mission are:
• Conduct a human exploration mission to an asteroid in
the mid-2020s, providing systems and operational experience required for human
exploration of Mars.
• Demonstrate an advanced solar electric propulsion
system, enabling future deep-space human and robotic exploration with
applicability to the nation’s public and private sector space needs.
• Enhance detection, tracking and characterization of
Near Earth Asteroids, enabling an overall strategy to defend our home planet.
• Demonstrate basic
planetary defense techniques that will inform impact threat mitigation
strategies to defend our home planet.
• Pursue a target of opportunity that benefits scientific
and partnership interests, expanding our knowledge of small celestial bodies
and enabling the mining of asteroid resources for commercial and exploration
needs.
What are the
requirements for the asteroid NASA hopes to capture?
NASA is working on two concepts for the mission: the
first is to fully capture a very small asteroid in open space, and the second
is to collect a boulder-sized sample off of a much larger asteroid. Both
concepts would require redirecting an asteroid mass less than 32 feet (10
meters) in size into the moon’s orbit.
NASA’s search for candidate asteroids for ARM is a
component of the agency’s existing efforts to identify all Near-Earth Objects
(NEOs) that could pose a threat to the Earth. More than 11,140 NEOs have been
discovered as of June 9. Approximately 1,483 of those have been classified as
potentially hazardous. Some of these NEOs become potential candidates for ARM
because they are in orbits very similar to Earth’s and come very close to the
Earth-Moon system in the early 2020s, which is required to be able to redirect
the asteroid mass to be captured into lunar orbit.
To date, nine asteroids have been identified as potential
candidates for the ARM full capture option, having favorable orbits and
estimated to be within the right size range. Sizes have been established for
three of the nine candidates. Another asteroid — 2008 HU4 — will pass close
enough to Earth in 2016 for interplanetary radar to determine some of its
characteristics, such as size, shape and rotation. The other five will not get
close enough to be observed again before the final mission selection, but
NASA’s NEO Program is finding a few additional potential candidate asteroids
every year. One or two of these get close enough to Earth each year to be well
characterized.
Boulders have been directly imaged on all larger
asteroids visited by spacecraft so far, such as Itokawa by the Japanese
Hayabusa mission, making retrieval of a large boulder a viable concept for ARM.
During the next few years, NASA expects to add several candidates for this
option, including asteroid Bennu, which will be imaged up close by the agency’s
Origins-Spectral Interpretation-Resource Identification-Security-Regolith
Explorer (OSIRIS-REx) mission in 2018. High resolution interplanetary radar is
also able to image the surfaces of asteroids that pass close to the Earth and
infer the presence of large boulders.
Where will the
asteroid be redirected to – reports suggest above the Moon?
After an asteroid mass is captured, the spacecraft will
redirect it to a stable orbit around the moon called a “Lunar Distant Retrograde
Orbit.” Astronauts aboard an Orion spacecraft, launched from a Space Launch
System (SLS) rocket, will explore the asteroid there in the mid-2020s. Learning
to maneuver large objects utilizing the gravity fields of the Earth and moon
will be valuable capabilities for future activities. Potentially, either
mission concept might test technology and techniques that can be applied to
planetary defense if needed in the future.
How will ARM fit
NASA’s goal to visit Mars?
The mission provides experience in human spaceflight
beyond low-Earth orbit, building on our experiences on the International Space
Station, and testing new systems and capabilities in the proving ground of
cis-lunar space, toward the ultimate goal of a crewed mission to Mars. ARM
leverages and integrates existing programs in NASA’s Science, Space Technology,
and Human Explorations and Operations to provide an affordable – and compelling
— opportunity to exercise our emerging deep space exploration capabilities on
the path to Mars. ARM will test the transport of large objects using advanced
high power, long life solar electric propulsion; automated rendezvous and
docking; deep space navigation; integrated robotic and crewed vehicle stack
operations in deep space environment; and spacewalks out of Orion that will be
needed for future cis-lunar space and Mars missions.
NASA’s strategy is that the ARM SEP module and spacecraft
bus would be upgradable for the first cargo missions to Mars and its moons. We
might do so by procuring these systems commercially to lower cost and for
reproducibility. Another option is to repurpose the ARM vehicle after its first
mission, as a lowest cost option for transportation. These are among the
options being studied this year.
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