Subtitles section Play video
-
How dark or light are asteroids. Join the 321Science team as we explore asteroid albedo.
-
What does "albedo" mean? It's a word created from the latin word "albus", which means white.
-
The root of the world albus is used in many common english words
-
Scientists use it to describe the amount of light reflected back from a surface and give it a value between 0 and 1.
-
How much light is reflected back from a surface? That depends on the surface material.
-
Very dark surfaces such as new asphault on a road reflect little, and absorb more of the light,
-
so they appear dark. Very light surfaces, such as sea ice or snow reflect a lot of light, so they appear bright.
-
Scientists measure the albedo of different,
-
well-known materials in labs. Astronomers measure the albedo of planets, moons, comets
-
and asteroids through telescopes. They compare albedos and spectral observations of asteroids
-
to learn about asteroid surfaces and composition
-
Bennu's albedo is .04 to .05, which tells scientists
-
that it is dark and probably carbon-rich. OSIRIS-REx's visit to Bennu will help scientists
-
refine the measurements of its albedo and other characteristics. To learn more about
-
Bennu, albedo and OSIRIS-REx, click on the links. This video is an OSIRIS-REx production.
-
OSIRIS-REx is a partnership of the University of Arizona, NASA Goddard Space Flight Center
-
and Lockheed Martin.