The four terrestrial planets in our solar system, also known as the "rocky planets," are Mercury, Venus, Earth, and Mars. These planets are named for their rocky, solid surfaces, in contrast to the gas giants, which are made up mostly of gas and have no solid surface.
The terrestrial planets are known for their close proximity to the sun and their relatively small size compared to the gas giants. Mercury, the smallest planet in the solar system, is only slightly larger than Earth's moon and is the closest planet to the sun. Venus is the hottest planet in the solar system, with surface temperatures reaching up to 864 degrees Fahrenheit (462 degrees Celsius). Earth is the third planet from the sun and is the only known planet to harbor life. Mars is the fourth planet from the sun and is known for its reddish appearance, caused by iron oxide (rust) on its surface.
Despite their similarities, each of the terrestrial planets has its own unique features and characteristics. Mercury, for example, has a heavily cratered surface and no atmosphere to speak of. Venus, on the other hand, has a thick, toxic atmosphere that traps heat and makes its surface inhospitable to life. Earth, of course, is the only planet known to support life, thanks to its atmosphere, liquid water, and a range of temperatures that allow for the existence of diverse ecosystems. Mars, meanwhile, has a thin atmosphere and evidence of past water on its surface, making it a target for exploration and potentially even colonization in the future.
In summary, the four terrestrial planets are known for their close proximity to the sun, solid surfaces, and relatively small size compared to the gas giants. Each of these planets has its own unique features and characteristics, making them fascinating objects of study for scientists and a source of endless fascination for the general public.