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.
2002 December 13
Explanation: During a total solar eclipse, the Sun's extensive outer atmosphere or corona is an awesome and inspirational sight. Yet the subtle shades and shimmering features of the corona that engage the eye span a brightness range of over 10,000 to 1, making them notoriously difficult to capture in a photograph. Still, this single five second exposure comes very close to revealing the crown of the Sun in all its glory. The colour picture was taken with a specially built coronal camera and telescope during the December 4th total eclipse from Messina, South Africa. The camera's design incorporates a precisely made filter whose density, or ability to block light, decreases markedly with distance from the filter centre, compensating for the difference between the brighter inner portion of the corona at the Sun's edge and the much fainter outer regions. The central spot in the image corresponds to a calibration window centred on the eclipsed Sun.
Authors & editors:
Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& NASA SEU Edu. Forum
& Michigan Tech. U.