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Sun activity |
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Click on images to see them in higher resolution
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Actual Sunspots seen by SOHO Michelson Doppler Imager |
Solar Terrestrial Activity Report from dxlc home page |
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| Image source: http://umbra.nascom.nasa.gov | Image source: http://dxlc.com |
| SOHO Extreme ultraviolet Imaging Telescope (EIT) full-field He II ] |
White-light Mk. 4 coronameter image |
 full-field He II 304')) |
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| Image source: http://umbra.nascom.nasa.gov | Image source: http://umbra.nascom.nasa.gov |
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Day-night location The image below gives the present location of day and night on the earth. The white area on the map are those locations in day; the grey indicates twilight; and the black is night.
Propagation along the
twilight zone
is very efficient. One major reason for this is that the D layer, which
absorbs HF signals, disappears rapidly on the sunset side of the
twilight zone,
and it has not yet built upon the sunrise side. |
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Image source: http://www.ips.gov.au |