Atmosphere of Earth However, polar stratospheric or nacreous clouds are occasionally seen in the lower part of this layer of the atmosphere where the air is coldest. The stratosphere is the highest layer that can be accessed by jet-powered aircraft. The troposphere is the lowest layer of Earth's atmosphere. It extends from Earth's surface to an average height of about , although this altitude varies from about at the geographic poles to at the Equator, with some variation due to weather. The troposphere is bounded above by the tropopause, a boundary marked in most places by a temperature inversion (i.e. a layer of
The Who, What, or Where Game of "Jackpot" that aired between 1985 and 1988 on the USA Network. After unsuccessfully attempting to revive the series in 1988 with a failed pilot called "The New Who, What or Where Game", Ron Greenberg later reformatted the show as "The Challengers", hosted by Dick Clark. "The Challengers" incorporated elements from "The Who, What, or Where Game" alongside a mix of topical questions in categories dealing with current events. Jonathan Lethem's 2013 novel "Dissident Gardens" has as part of its plot a character who appears on this show, which is mentioned by name, as is host Art James. The music