Origin of REPHAIM. Hebrew rÄphÄ'Ä«m. This word doesn't usually appear in our free dictionary, but the definition from our premium Unabridged Dictionary is offered here on a limited basis. Note that some information is displayed differently in the Unabridged.To access the complete Unabridged Dictionary, with an additional 300,000 words that aren't in our free dictionary, start a free trial.efinition of REPHAIM. : ancient giants reported in the Old Testament to have flourished in Canaan and its vicinity prior to the Hebrews. ADVERTISEMENT.
In this lesson, we're going to cover the thermosphere, the layer of atmosphere right before we get to outer space. To understand where the thermosphere is, we need to understand the other layers of the atmosphere starting from Earth's surface. Near the surface to about 7 miles above is the troposphere. This is where clouds we see in the sky are. Near the edge of the troposphere and into the next layer, the stratosphere, is where airplanes fly. The stratosphere extends from 7 miles above the surface to about 20 miles above the surface. After the stratosphere is the mesosphere, which extends upward to 50 miles above the surface. After the mesosphere, we have our focus layer for today, the thermosphere. The thermosphere extends from about 50 miles above the surface of Earth to about 600 miles above our planet. Beyond that is the exosphere, which is the layer that turns into outer space at the edge.
The troposphere is the lowermost portion of Earth's atmosphere and the one in which most weather phenomena occur; this layer extends to an altitude of 7-17 km, depending on latitude. Generally, jets fly near the top of this layer. The troposphere is directly below the stratosphere. The word troposphere stems from the Greek tropos for turning or mixing. This region, constantly in motion, is the densest layer. Nitrogen and oxygen are the primary gases, within this region. The tropopause marks the limit of the troposphere and the beginning of the stratosphere. The temperature above the tropopause increases slowly with height up to about 50 km. In telecommunication, the term troposphere has the following meanings: 1. The lower layers of atmosphere, in which the change of temperature with height is relatively large.