The Sun in a new light

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While observing the Sun from December 22–27, physicists using the Solar and Heliospheric Observatory (SOHO) received a Christmas present. With its large‐angle spectrometric coronagraph (LASCO), SOHO captured this photograph of the Sun against the backdrop of the Milky Way—with a dying comet streaking toward the star. In the center of the photo, LASCO's occulting disk (light blue shading) blocks the solar surface (white circle) and the nearby environment—out to three solar radii—in order to allow studies of the corona. Solar streamers, a source of solar wind, blow out from the equator and stretch as far as 20 million km from the surface. In this image, SOHO is peering toward the heart of the Milky Way, with the Sun drifting in front of the stars of the constellation Sagittarius and heading toward Capricorn. By capturing the Sun in its place in the Milky Way galaxy, SOHO provided one of the first direct views of a starfield behind the Sun (from Earth's perspective). At eight o 'clock on the edge of the occulting disk, Comet SOHO 6 plunges toward its demise. The comet was part of the family of “sungrazers,” remnants of a large comet that is believed to have broken up 900 years ago. SOHO 6—one of seven sungrazers detected by LASCO last year—curved toward the Sun and disappeared from view by December 24, presumably burning up during descent through the corona. Several movies and still photographs of the Sun can be viewed on the World Wide Web at http://lasco‐www.nrl.navy. mil/lasco.html. [Photo courtesy of NASA, the European Space Agency, and the U.S. Naval Research Laboratory].