سؤال قراءة ستيب محلول — فهم التفاصيل (تدريب 6947)

(1) The home address of the earth is the third planet in the solar system of the sun, which is a medium-sized star on the edge of the Milky Way galaxy. Its distance from the sun is 93 million miles. The solar system consists of the sun and nine known planets, as well as other celestial bodies that orbit the sun. The solar system also contains comets, spheres covered with ice and dust that leave trails of vapor as they race through space. Asteroids, large chunks of rocky material, are found in space as well. Our solar system has an asteroid belt between the orbits of Jupiter and Mars. The Structure of the Earth (2) The earth is about 24,900 miles in circumference and about 7,900 miles in diameter. Although the earth seems like a solid ball, it is really more like a series of shells that surround one another. Inside the Earth (3) The core is the center of the earth and is made up of iron and nickel. The outer core is liquid, but the inner core is solid. Surrounding the core is the mantle, which has several layers. The mantle contains most of the earth mass. Magma, which is molten rock, can form in the mantle and rise through the crust, the thin layer of rock at the earth surface What is one important idea related to the earth that the author mentions?