In space exploration, in situ resource utilization ( ISRU ) is the
practice of collection, processing, storing and use of materials found or
manufactured on other astronomical objects (the Moon, Mars, asteroids, etc.)
that replace materials that would otherwise be brought from Earth.
ISRU could provide materials for life support, propellants, construction
materials, and energy to a spacecraft payloads or space exploration crews. It
is now very common for spacecraft and robotic planetary surface mission to
harness the solar radiation found in situ in the form of solar panels.