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Lightning Cloud Burst Boulder County Colorado IM34
Image by Striking Photography by Bo Insogna
Colorful light reflections, Lightning Cloud Burst Boulder County Colorado IM34. Boulder County, Colorado cloud to cloud lightning thunderstorm cell April 25th,2011
Cloud-to-cloud lightning
Multiple paths of cloud-to-cloud Lightning discharges may occur between areas of cloud without contacting the ground. When it occurs between two separate clouds it is known as inter-cloud lightning and when it occurs between areas of differing electric potential within a single cloud, it is known as intra-cloud lightning. Intra-cloud lightning is the most frequently occurring type.[14]
These are most common between the upper anvil portion and lower reaches of a given thunderstorm. This lightning can sometimes be observed at great distances at night as so-called "heat lightning". In such instances, the observer may see only a flash of light without hearing any thunder. The "heat" portion of the term is a folk association between locally experienced warmth and the distant lightning flashes.
Another terminology used for cloud-cloud or cloud-cloud-ground lightning is "Anvil Crawler", due to the habit of the charge typically originating from beneath or within the anvil and scrambling through the upper cloud layers of a thunderstorm, normally generating multiple branch strokes which are dramatic to witness. These are usually seen as a thunderstorm passes over the observer or begins to decay. The most vivid crawler behavior occurs in well developed thunderstorms that feature extensive rear anvil shearing. Source: Wikipedia
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STS-125: Working on the Hubble telescope [1680x1050]
Image by DUCKofD3ATH
This is a composite of two images.
Source: NASA
Full Moon 2005-11-15
Image by Michael Karrer
10cm/f8 Takahashi Refractor,
mosaic, enhanced colours, Imaging Source DBK 21AF04