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spicule
spicule A spike-like jet in the upper chromosphere of the Sun, visible especially in Hα light. Spicules rise upwards into the corona at velocities of about 30 km/s, reaching altitudes of 9000 km in about 90 s. They last about 15 min, ending their lives by fading rather than descending. They tend to be clustered, giving the appearance of porcupine quills on the solar limb. Seen against the disk, in Hα light, they seem to be identifiable as fine mottles, light or dark depending on their height (although they always appear dark when observed in the red line wing of the Hα line). Fine mottles form clusters with their bases in the coarse mottles which outline the chromospheric network. At the centre of the Sun's disk, clumps of spicules form radiating patterns called rosettes.
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"spicule." A Dictionary of Astronomy. 1997. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. "spicule." A Dictionary of Astronomy. 1997. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O80-spicule.html "spicule." A Dictionary of Astronomy. 1997. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-spicule.html |
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spicule
spicule A small needle or spine, or a small, spiky, skeletal element. In Porifera (sponges), spicules form a skeletal framework supporting the soft, cellular mass. They exist in a variety of forms and are important in the identification and classification of species. An extensive nomenclature has developed through the use of these structures in poriferan taxonomy (e.g. they may be described as monoaxon, tetraxon, triaxon, hexaxon, polyaxon, megasclere, or microsclere). Spicules may be calcareous, siliceous, or of a fibrous material (spongin).
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MICHAEL ALLABY. "spicule." A Dictionary of Zoology. 1999. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "spicule." A Dictionary of Zoology. 1999. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O8-spicule.html MICHAEL ALLABY. "spicule." A Dictionary of Zoology. 1999. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-spicule.html |
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spicule
spicule (spik-yool) n. a small splinter of bone.
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"spicule." A Dictionary of Nursing. 2008. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. "spicule." A Dictionary of Nursing. 2008. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O62-spicule.html "spicule." A Dictionary of Nursing. 2008. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-spicule.html |
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spicule
spicule see chromosphere . |
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"spicule." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. "spicule." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1E1-X-spicule.html "spicule." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-spicule.html |
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spicule
spicule A small needle or spine.
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AILSA ALLABY and MICHAEL ALLABY. "spicule." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "spicule." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O13-spicule.html AILSA ALLABY and MICHAEL ALLABY. "spicule." A Dictionary of Earth Sciences. 1999. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-spicule.html |
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spicule
spicule A small needle or spine.
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MICHAEL ALLABY. "spicule." A Dictionary of Ecology. 2004. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "spicule." A Dictionary of Ecology. 2004. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O14-spicule.html MICHAEL ALLABY. "spicule." A Dictionary of Ecology. 2004. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-spicule.html |
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spicule
spicule A small needle or spine.
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MICHAEL ALLABY. "spicule." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "spicule." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O7-spicule.html MICHAEL ALLABY. "spicule." A Dictionary of Plant Sciences. 1998. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-spicule.html |
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