Which of the following is not a terrestrial planet?
A. Venus
B. Uranus
C. Mars
D. Earth
B. Uranus
The answer is B. Uranus. Uranus is not considered a terrestrial planet. It is classified as an ice giant planet, along with Neptune. The terrestrial planets are those that are mainly composed of rock and metal, such as Venus, Mars, and Earth.
To determine which of the given options is not a terrestrial planet, we need to understand what terrestrial planets are and then identify the one that does not fit the criteria.
Terrestrial planets, also known as rocky planets, are those that share similar characteristics to Earth. The key distinguishing features of terrestrial planets are a solid surface and a compact, rocky composition. These planets are primarily composed of silicate rocks or metals, and they tend to have thin or no atmospheres.
Now let's examine each option:
A. Venus: Venus is a terrestrial planet. It has a solid surface and a rocky composition, making it one of the four terrestrial planets in our solar system.
B. Uranus: Uranus, on the other hand, is not a terrestrial planet. It is classified as a gas giant rather than a rocky planet. Gas giants are composed mostly of hydrogen and helium, with only a relatively small rocky core.
C. Mars: Mars is also a terrestrial planet. It has a solid surface and a rocky composition, similar to Earth, making it one of the four terrestrial planets in our solar system.
D. Earth: Earth is undoubtedly a terrestrial planet. It meets all the criteria of having a solid surface and a rocky composition.
Therefore, the answer is B. Uranus, as it is not a terrestrial planet.