spacetoday.net: Astronomers take 3-D images of solar surface

Posted: Wed, Jun 18, 2003, 9:25 PM ET (0125 GMT)
Solar surface (LMSAL)

Astronomers have taken the first three-dimensional photos of the photosphere, or solar surface. At the annual conference of the American Astronomical Society's Solar Physics Division a team of US, Norwegian, and Swedish astronomers released the images, taken using the one-meter Swedish Solar Telescope at La Palma. The images were taken of the limb of the Sun, allowing astronomers to see the relief created by features on the photosphere, and thus provide a 3-D view of the surface. The images in particular show that regions of smaller magnetic fields outside of sunspots are higher than regions with no magnetic activity. These raised regions, or faculae (Latin for "little torches"), are up to 400 kilometers tall and are also brighter than surrounding areas. These areas, more common during periods of high sunspot activity, may explain why the Sun is about 0.1 to 0.15 percent brighter then compared to periods of low activity.