Image 1 above: The SAIC team used surface data like the magnetic map at left to derive and predict the future appearance of the entire solar corona (represented by the ultraviolet lower coronal image at right). At left, a magnetic image of the Sun's surface acquired on March 21, 2006 by the MDI instrument on the SOHO spacecraft shows north (white) and south (black) magnetic poles dotting the surface. At right, the corresponding ultraviolet image of the corona acquired by the EIT instrument on SOHO shows that magnetized regions affect the structure of the Sun's atmosphere. Credit: NASA/ESA (+ High Res .tif #1)
Images 2-4 above: Researchers set out to predict the view of the solar atmosphere, or corona, which is most easily observed during an eclipse. Images on the far left and center show two representations from the model while the right image shows a composite of the eclipse using a photograph of the corona (gray) taken in Kastellorizo, Greece, by the Williams College Eclipse Expedition. The sun's surface and the solar plasma streaming out into space (both orange) come from the Solar and Heliospheric Observatory (SOHO) spacecraft. Click on images to download larger versions. Credit #2-3: SAIC/NASA/NSF. Credit #4: The Williams College Eclipse Expedition with support from NSF/NASA/National Geographic. (+ High Res .tif #2 | + High Res .tif #3 | + High Res .tif #4 | + More Prediction Information | + More Comparison/Observation Information)
Images 5 and 6 above: Here the researcher's models (orange) reveal an ability to predict coronal holes – low density regions extending above the surface where the solar magnetic field opens freely into interplanetary space. They are also the source of the high-speed solar wind, atoms and electrons that flow outward along the open field lines. The actual images come from the Solar X-ray Imager on the GOES weather satellite. Click on images to download larger versions. Credit #5: SAIC/NASA/NSF. Credit #6: NOAA.
Images 7-9 above: The corona is only visible from Earth during an eclipse and because it's always changing, each eclipse looks different. The first two images show predictions from the model while the third shows the March 29, 2006 eclipse as viewed from Sidi Barany, Egypt. Click on images to download larger versions. Credit #7-8: SAIC/NASA/NSF. Credit #9: Jean Mouette, Serge Koutchmy, CNRS. (+ High Res .tif #7 | + High Res .tif #8 | + High Res .tif #9)
Images 10 and 11 above: Images obtained one year apart from one solar maximum, starting on the lower right, to the next, showing the solar magnetic field (left) and the soft x-ray corona (right). The evolution of coronal structure occurs as a result of the changes in the magnetic fields at its base. Note the diminished magnetic field features and lack of x-ray bright loops in the middle of the sequence, at solar minimum. Click on images to download larger versions. Credit: Lockheed Martin Solar & Astrophysics Lab, Yohkoh SXT and Kitt Peak National Solar Observatory
Image 12 above: Animated sequence of eclipse images - The white light corona seen by eclipse observers also shows the solar cycle changes in the corona since the previous solar minimum in 1994. Click on the image to download larger versions. Credit: NSF/NASA/SAIC/NCAR/UCAR/Wendy Carlos/Kitt Peak National Solar Observatory/High Altitude Observatory/National Astronomical Observatory of Japan/National Geographic/Williams College/Meisei University (+ 1994 Larger Image | + 1997 Larger Image | + 1998 Larger Image | + 1999 Larger Image | + 2001 Larger Image | + 2002 Larger Image | + 2006 Larger Image | + Additional Eclipse Images)
Image 13 above: This animated image is made up of a composite of SOHO Extreme Ultraviolet and white light coronagraph images, showing a coronal mass ejection (CME). CMEs that erupt near the central disk of the Sun can cause major geomagnetic storms and space weather effects. Future simulations incorporating such dynamical coronal behavior are the goal of major agency efforts such as the NSF Center for Integrated Space Weather Modeling and NASA's Living with a Star and STEREO mission programs. Click on the image to download larger versions. Credit: NASA/ESA/Seiji Yashiro CDAW LASCO CME Catalog