The terrestrial planets ranked in order of decreasing atmospheric density are Venus, Earth, Mars, Mercury. A terrestrial planet, telluric planet, or rocky planet is a planet that is composed primarily of silicate rocks or metals. Within the Solar System. It is the terrene planets are the inner planets nearest to the Sun.
A gravel covered plain is called a Reg. A reg is a desert basin where the sand has been blown away leaving a gravel covered plain.
The mesosphere burns up most meteors and asteroids before they are able to reach the earth's surface.The mesosphere is the coldest atmospheric layer surrounding the earth. It becomes cold enough to freeze water vapor in its atmosphere into ice clouds.
