[Music]
How does one spacecraft image an asteroid from as far away as
a million kilometers, or as close as just a few meters?
Accomplishing this task is the job of OCAMS: the OSIRIS-REx camera suite.
NASA's OSIRIS-REx mission is headed to near-Earth asteroid
Bennu, a remnant from the dawn of the solar system.
OCAMS sits on the OSIRIS-REx instrument deck, which will face Bennu during orbit.
It consists of three cameras built by the University of
Arizona, each designed to provide the mission with a unique perspective.
PolyCam is a reflecting telescope with an eight-inch
mirror and a narrow field of view, which will acquire both
long-range and close-up images of Bennu.
MapCam is a medium-angle camera, which will map Bennu in color.
SamCam is a wide-angle camera that will record the most
crucial moment of the OSIRIS-REx mission.
OSIRIS-REx will spend nearly two years traveling from Earth
before approaching Bennu in 2018.
PolyCam will be the first instrument to spot the asteroid,
as a faint speck of light up to two million kilometers away.
As OSIRIS-REx approaches Bennu, it will switch from navigating
by using radar ranging from the Earth to using OCAMS to refine
the asteroid's position and to ensure a smooth transition to proximity operations.
Over the next year, the OCAMS suite will scan Bennu at various
resolutions, providing global maps and close-up images.
MapCam will use its color filters for spectral imaging,
revealing clues about the asteroid's composition through
subtle changes in its color and brightness.
In 2019, OSIRIS-REx will make a series of close passes of Bennu,
allowing PolyCam to image portions of the surface with sub-centimeter resolution.
These images will prepare OSIRIS-REx for its most
important task, which will be documented by the wide-angle SamCam.
After more than a year in orbit, OSIRIS-REx will slowly approach
Bennu's surface to grab a sample of the asteroid.
SamCam will capture the event in a series of rapid-fire images.
This visual record will help scientists understand the
context of the returned material.
In 2023, OSIRIS-REx will deliver its sample of Bennu to Earth,
where scientists will study the sample for decades to come.
OSIRIS-REx is investigating asteroid Bennu, and OCAMS will
provide the first close-up look at this ancient remnant of the
solar system – revealing clues to Bennu's history, and our own.
[Music, satellite beeping]