![Request for Information – Potential [Placeholder for Prize]](https://assets.science.nasa.gov/dynamicimage/assets/science/psd/solar/2023/09/s/solarsystem_0.jpg?w=1024)
APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
X-Raying the Moon
Explanation: Above is a picture of the Moon taken in X-rays by the Roentgen Observatory Satellite ROSAT in 1990. This famous picture shows three distinct regions: a bright X-ray sky, a bright part of the Moon, and a relatively dark part of the Moon. The bright X-ray region is exemplary of the mysterious X-ray background that is seen everywhere on the sky. The bright lunar crescent shines because it reflects X-rays emitted by the Sun . The dark lunar face is surprising because it is not completely dark, and its slight emission is thought to result from energetic particles from the solar wind striking the Moon.
| Date | August 31, 1995 |
|---|---|
| Credit | Credit: DARA, ESA, NASA, Max Planck Institut, J.H.M.M. Schmitt |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |