See no ads on this site, see our videos early, special bonus material, and much more. Mercury is the smallest planet and is the closest to the Sun. Venus’ clouds are not made of water vapor like Earth’s clouds. And our Moon, the only one we have, is comprised of a mixture of various rocks and minerals. In fact, the extent of Valles Marineris is as long as the United States and it spans about 20 percent (1/5) of the entire distance around Mars. 1. The Martian atmosphere is very thin relative to Earth’s and has much lower atmospheric pressure. Our Solar System is made up of different regions, which are delineated based on their distance from the Sun, but also the types of planets and bodies that can be found within them. warmer. We know that Earth has what living things need. Venus is also our nearest neighbor. ... Uranus and Neptune contain some hydrogen and helium but also ices of ____ and ____. Phobos and Deimos are named after characters in Greek mythology — the two sons of Ares, who followed their father into war. The Moon is covered with craters; it also has large plains of lava. It has the right amount of sunlight. It’s difficult for scientists to figure out the geological history of Venus. Much of the surface is very old and filled with craters, but there are geologically newer areas of the planet as well. Identify two places where you might be able to get water on the planet. There is also the red planet, called Mars, where ast… Like the Moon, it is covered with craters. The volcano’s base is about the size of the state of Arizona. This rotation is extremely slow, only one turn every 243 days. a. salinity (how much salt) of the water and high temperaturesb. Earth. Uranus and Neptune are the outer ice giants. Another name for the outer planets is _____. Earth has fewer impact craters than Mercury and the Moon too. The terrestrial inner planets are composed largely of refractory minerals, such as the silicates, which form their crusts and mantles, and metals such as iron and nickel which form their cores. All of the inner planets are small, relative to the outer planets. As yet Earth is the only planet known to have life. Both were discovered in 1877 and are thought to be captured asteroids. The presence of liquid water, the ability of the atmosphere to filter out harmful radiation, and many other features make the planet uniquely suited to harbor life. Beyond the frost line, these compounds condense into ice grains.Some scientists refer to the frost line as the “Goldilocks Zone” — where conditions for life may be “just right.”. Earth’s crust is divided into tectonic plates, which move around on the surface because of the convecting mantle below. The inner planets (Mercury, Venus, Earth, and Mars) are also called the terrestrial planets (Earth-like). Of course, the inner planets have shorter orbits around the Sun, and they all spin more slowly. All of the inner planets are solid, dense, rocky planets. Join our 836 patrons! 88 days. This image of Mars, taken by the Hubble Space Telescope in October, 2005, shows the planet’s red color, a small ice cap on the south pole, and a dust storm. This composite shows the relative sizes of the four inner planets. Rotates opposite. In addition to their proximity, these planets have a number of key differences that set them apart from planets elsewhere in the Solar System. Venus is often called the “morning star” because, with the exception of Earth’s moon, it’s the brightest object we see in the sky. Water cannot stay in liquid form on Mars because the atmospheric pressure is too low. By comparison, the Grand Canyon on Earth is only 446 km (277 mi) long and about 2 km (1.2 mi) deep. But the surface is not red from blood but from large amounts of iron oxide in the soil. (a) Mariner 10 made three flybys of Mercury in 1974 and 1975. Mercury Space probes, rovers, and orbiting satellites have all yielded information to planetary geologists. Much of Venus’ surface is marked with volcanoes and deep canyons — the biggest of which is over 6400 km (4,000 mi) long. The inner planets (Mercury, Venus, Earth and Mars) all have a stony surface, whereas the outer planets (Jupiter, Uranus and Neptune) have no real surface, but they are so-called "gas giants", that are mostly composed of more or less liquid gases. The atmosphere of Venus is full of acid, its pressure is crushing, and the enormous amount of carbon dioxide causes runaway greenhouse effect(4d): http://www.youtube.com/watch?v=HqFVxWfVtoo (2:05). With its extremely thin atmosphere, Mercury has a large temperature range. That is why terrestrial planets are also called “Earth-like” planets, due to the similarity in the structure of the planet Earth. Venus:. Water is a liquid at this temperature, but the planet also has water in its other two states, solid and gas. Mars also has the largest canyon in the solar system, Valles Marineris (Figure  below). Unlike the outer planets, which have many of satellites, Mercury and Venus do not have moons, Earth has one, and Mars has two. The planet has two small moons called Phobos and Deimos. For starters, the inner planets are rocky and terrestrial, composed mostly of silicates and metals, whereas the outer planets are gas giants. The four inner planets, or terrestrial planets, have solid, rocky surfaces. Mars has two small moons, Phobos (left) and Deimos (right). With its thick, corrosive atmosphere, the surface temperature is extremely high. 2. Fill in the blank with the appropriate term. Three of the four inner planets (Venus, Earth and Mars) have atmospheres substantial enough to generate weather. Although most of Mercury is extremely dry, scientists think there may be a small amount of water in the form of ice at the poles of Mercury, in areas that never receive direct sunlight. The innermost planet is _____. Mercury is named for the Roman messenger god, who could run extremely quickly, just as the planet moves very quickly in its orbit around the Sun. Because of their similarity to Earth, the inner planets are also called _____. Olympus Mons is about 27 km (16.7 miles/88,580 ft) above the Martian surface, more than three times taller than Mount Everest. 3. The canyon is 7 km (4.3 mi) deep. The only planet that has a large moon is _____ Iron liquid core. Sorry, your blog cannot share posts by email. Earth’s atmosphere protects the planet from dangerous radiation and helps keep valuable sunlight and warmth in, which is also essential for life to survive. Terrestrial. The huge number of craters suggests that Moon’s surface is ancient. 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