"earth"

In this 5.5 million-year-old cave, not only is there no sunlight, but the environment is also very harsh

Since there are many lakes in China, many of them have the title of "largest".

The Big Dipper is located in the constellation Ursa Major, and under good observing conditions, we can find them almost every day in the night sky of the Northern Hemisphere. These seven shining stars form a unique spoon shape that is very easy to recognize.

Earthquakes are a common natural phenomenon. On average, millions of earthquakes occur on Earth every year, except that most of them are so mild that they are largely imperceptible to humans.

NASA's Jet Propulsion Laboratory's Near Earth Object Research Center has such a database, which is called the "Fireball Database."

The modern Earth's atmosphere is so rich in oxygen that the vast majority of this hydrogen will be re-oxidized to water without escaping from the Earth's top atmosphere

Because Mercury does not have an atmosphere to play a role in insulation, so the temperature of the back side of Mercury can be as low as minus 172 degrees Celsius, and because of the proximity of the sun, the temperature of the sunny side of Mercury will soar to 432 degrees Celsius under the baking of the sun, so it can be seen that Mercury is simply a realistic version of the "world of ice and fire"

Since the discovery of the first exoplanet in the 1990s, scientists have found more than 4,000 exoplanets, some like the giant gas planets of our solar system, and others like earth-like planets. Some exoplanets may have very harsh environments, perhaps as hot as venus or mercury, or as extremely cold as other planets. Of course there are also exoplanets that may have relatively suitable temperatures, may be located in the habitable zone of a star system, are a potentially habitable planet, and may even be a living planet.

If humans evolved from the forest archaeopteryx, how did the forest archaeopteryx emerge?

Titan is the largest moon of Saturn and the second largest in our solar system, even a little larger than Mercury, one of the eight planets. Due to tidal locking, Titan's rotation period and revolution period are the same, similar to our Moon