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The Sun Spews X-rays
| Title |
The Sun Spews X-rays |
| Explanation |
Our Sun [ http://antwrp.gsfc.nasa.gov/apod/ap950813.html ] is really very hot. The Sun's outer atmosphere is so hot that it emits much light in the X-ray [ http://antwrp.gsfc.nasa.gov/apod/lib/glossary.html#X-ray ] band, which was unexpected. X-rays are usually emitted from objects having a temperature in the millions of degrees, not the mere thousands of degrees of the Sun's surface. The above X-ray picture shows the Sun [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/sol.html ] one particularly active day in August of 1992. Evident are hot spots on the solar surface, showing that areas above the Sun [ http://www.hao.ucar.edu/public/slides/slides.html ]'s surface really do reach millions of degrees. But possibly more puzzling is the broader X-ray glow visible surrounding the Sun [ http://www.c3.lanl.gov/~cjhamil/SolarSystem/sun.html ]. This glow is now attributed to the Sun's X-ray corona [ http://umbra.nascom.nasa.gov/spartan/the_corona.html ], the origin of which is currently a subject of much discussion and debate. The Sun [ http://spacelink.msfc.nasa.gov/Instructional.Materials/Curriculum.Materials/Sciences/Astronomy/Our.Solar.System/Our.Sun/The.Sun ] is one of the most photographed objects, with frequently updated pictures available [ http://umbra.nascom.nasa.gov/images/latest.html ] over the WWW. In fact, an X-ray picture from Yohkoh taken earlier today is usually available over the WWW. Compare it to the above picture! |
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Solar Magnetic Bananas
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Solar Magnetic Bananas |
| Explanation |
Is that our Sun [ http://www.seds.org/nineplanets/nineplanets/sol.html ]? The unusual banana [ http://www.dole5aday.com/bobby/shocked_audio/radio_swa_letsgo.html ]-shaped loops shown above [ http://science.msfc.nasa.gov/newhome/headlines/ast22jun98_1.htm ] are actually part of a computer-generated snap-shot of our Sun's magnetic field [ http://vestige.lmsal.com/TRACE/Public/magnetic.htm ]. This animated frame [ http://science.msfc.nasa.gov/ssl/pad/solar/3dfields.htm ] was constructed using data from the ground-based U.S. Solar Vector Magnetograph [ http://wwwssl.msfc.nasa.gov/ssl/pad/solar/maggraph.htm ] and the space-based Japanese X-Ray Telescope Yohkoh [ http://solar.physics.montana.edu/YPOP/ ]. Surfaces of constant magnetic field [ http://www-spof.gsfc.nasa.gov/Education/Imagnet.html ] strength loop through the Sun's corona [ http://antwrp.gsfc.nasa.gov/apod/ap951024.html ], break through the Sun's surface, and connect regions of magnetic activity such as sunspots [ http://antwrp.gsfc.nasa.gov/apod/ap980322.html ]. Recently, contact has been interrupted [ http://sohowww.nascom.nasa.gov/pr26june.html ] with the Sun-watching SOHO [ http://sohowww.nascom.nasa.gov/ ] satellite. Although SOHO had completed its two year mission, attempts are still being made to re-establish communication. |
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