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  • 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.

How dark or light are asteroids. Join the 321Science team as we explore asteroid albedo.

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B1 中級 美國腔

什麼是反射率? (What is Albedo?)

  • 92 12
    羅紹桀 發佈於 2021 年 01 月 14 日
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