Extraterrestrial

It's good news that Earth has regained contact with Voyager 2 after such a long period of loss of control. But somewhat sadly, Voyager 2 is carrying very little battery power left

The so-called gravitational equilibrium surface refers to the surface formed by the same point of gravity. On Earth, we call the gravitational equilibrium surface that coincides with the stationary ocean surface the "geodetic level", which is actually equivalent to what we often call sea level.

Although the Earth is just a "grain of dust suspended in the sun" in the universe, for us humans, this "grain of dust" is irreplaceable.

The sun, which we call the 'source of all things', has been sending light and heat to the earth for the past 4.6 billion years, which is why the earth is such a vibrant planet.What exactly does the sun use as fuel and how has it been able to burn for 4.6 billion years without going out?

Compared to radio messages sent by humans, this method seems to be more suitable for intelligent civilizations to announce their presence in the universe, because this method belongs to the "broadcast" in space, and intelligent civilizations in all directions can be observed

Like Earth, Titan has a nitrogen-rich atmosphere, with 98.44% of its atmosphere being nitrogen, making it the only nitrogen-rich planet in the solar system other than Earth.

Between the Earth and the Moon there exists a much more empty space than imagined, so what can be put down in this space?

According to astronomers, Barnard's star is approaching the Sun at a rate of about 107 kilometers per second, and on this trend, it will arrive at a distance of 3.85 light-years from the Sun in 11800 AD, replacing Proxima as the closest star to the Sun

If a shot is fired at the moon from the space station, the bullet fired will be firmly bound by the earth's gravity and it will be impossible to hit the moon

The "Ryder" crater is actually located on the rim of a much larger crater. Exploration data show that this old crater is about 70 km in diameter, and its rim rises high above the inner area, with an altitude difference of about 3 km