This is an X-ray image of the Sun taken with the Soft X-Ray Telescope (SXT) on the orbiting Yohkoh satellite. This is an example of the deep, red images of the Sun you might've seen. This particular image was taken on November 23, 1999.
Click on image for full size
ISAS/Yohkoh team/Lockheed Palo Alto Research Laboratory

Yohkoh Mission

Have you seen a deep, red picture of the Sun like the one on this page? Do you know where it came from? The Yohkoh satellite may have taken it! Yohkoh was launched from Japan in 1991. For over ten years, it has been sending back images of the Sun in X-ray and gamma ray light. X-ray and gamma ray light are regions of light we can't normally see with our eyes! That's why we need Yohkoh to do the looking and picture taking for us.

The Yohkoh satellite helps scientists study solar flares. Flares are fast bursts of light given off by the Sun. They are full of X-rays and gamma rays, and scientists want to know why. Yohkoh is also used to study coronal mass ejections and other solar activity.

Yohkoh has been experiencing problems since December 2001. The trouble was started by an eclipse of the Sun. Even if the Japanese space program can't get Yohkoh out of trouble, the mission can be counted as a great success.

Last modified January 9, 2002 by Jennifer Bergman.

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