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.
Words nearby transition region
Scientific 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.