The Solar Corona in 3-D

This anaglyph image, made from two images from the Soft X-ray Telescope on board the Japanese/US/UK spacecraft Yohkoh, shows the Sun's appearance in the X-ray waveband from 3 to 45 Angstrom units. The bright material seen in the images is hot, rarefied gas of the Sun's outer atmosphere (the corona), glowing because of its high temperature of a million degrees Kelvin (or more). The forms of the gas clouds are determined by magnetic fields, which play a still mysterious role in their heating to such high temperatures, and sometimes cause the clouds to explode, emitting intense bursts of harmful radiations throughout the solar system. The effects of the radiations on the terrestrial environment are subjects of great interest as likely factors in climate change and as hazards to astronauts and spacecraft. Forecasting of solar flares would be a great advance, and thus the dynamics of these clouds is of keen interest. The composite anaglyph image represents a step towards better investigation of the physics of solar activity by obtaining more three-dimensional information about the coronal structures. In the time between the images (about 13.5 hours) the Sun's rotation provides a parallax via its rotation. The images have been registered and colored so that the viewer can view them with red/blue or red/green 3-D glasses, obtaining a quasi-stereoscopic view, as if one had eyes separated by one tenth the distance from Earth to the Sun. Much of the Sun's coronal structure was stable during this time, so depth can be perceived. The actual times are near 3 hr and 16 hr UT on 1992 Nov. 11.

The Yohkoh spacecraft is operated by the Japanese space agency ISAS. For more information about Yohkoh images, use WWW page

http://www.lmsal.com/SXT/homepage.html

or

http://umbra.gsfc.nasa.gov/sdac.html.

The stereo pair of Yohkoh images was made by Dr. David Batchelor of NASA/Goddard Space Flight Center (batchelor@nssdca.gsfc.nasa.gov).