transition region

noun Astronomy.

a thin and very irregular layer of the sun's atmosphere that separates the hot corona from the much cooler chromosphere.

Nearby words

  1. transition elements,
  2. transition gyrus,
  3. transition mutation,
  4. transition point,
  5. transition probability,
  6. transition team,
  7. transition temperature,
  8. transitional,
  9. transitional cell carcinoma,
  10. transitional denture Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Science definitions for transition region

transition region

The area in a seed-bearing plant where the vascular tissue of the root changes into the vascular tissue of the stem. In eudicotyledons, the roots have a solid cylinder of vascular tissue surrounded by cortex. The vascular tissues gradually branch apart and reorient themselves in the stem around a central pith.
The thin layer of the solar atmosphere that separates the chromosphere from the corona. In the transition region, temperatures increase from a relatively cool 20,000°K in the chromosphere to the 1,000,000°K and higher temperatures of the corona. Transition region chemistry involves the ionization of hydrogen and other elements; the light produced by this region comes from ionized forms of carbon, oxygen, and silicon.
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