spicules


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spicules

(spik -yoolz) Predominantly vertical narrow (1000-km diameter) jets of gas, visible (in the monochromatic light of certain strong Fraunhofer lines) beyond the Sun's limb. They ascend with velocities of up to 20–30 km s–1 from the lower chromosphere for several thousand kilometers into the inner corona and then fall back and/or fade away. Their average lifetime is 5–10 minutes. They are closely associated with the chromospheric network, being located in regions of enhanced vertical magnetic field at the boundaries of supergranular cells (see supergranulation), and have temperatures of the order of 10 000 to 20 000 K.
References in periodicals archive ?
Critically, they found that the properties of these simulations matched observations of real spicules by the Interface Region Imaging Spectograph and the Swedish Solar Telescope.
The spicules show promise for clearing this hurdle.
Typically, the skeleton is formed by spicules, calcareous or siliceous, or with an organic support.
They have a characteristic sunburst or honey comb radiating spicules from a round to oval defect.
Raman analysis of the crystals, present as the 'head' of the spicules as well as isolated clusters, using a 532 nm laser, confirmed they were quartz.
Freshwater sponges (Porifera: Spongillidae) from Lake Llopango, El Salvador, with observations on spicule malformation in Spongilla alba.
Clinically, it is characterized by spicules (minute fingerlike keratin projections) with colors ranging from skin-colored to yellow or brown, varying in size (0.
12] In our case hysteroscopic removal of the bony spicules and laparoscopy with adhesiolysis were successfully performed.
In addition, irregularly-shaped bone spicules were found surrounded by osteoblast-like cells, some of which had already undergone calcification (Fig.
It may also be differed in tridents nature, length of spicules and anal papillae number in males, and by the inflation of vulva lips in females and excretory pore position.