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

Although we do not know much about these two "super Earths" yet, but from the basic situation, these two "super Earths" are not suitable for human habitation

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"

At the time of the "family photo" of the solar system, the Voyager 1 probe has reached a distance of 6.4 billion kilometers from Earth, very distant, so in the view of the Voyager 1 probe, the solar system, the major celestial bodies are very small

Intelligent life is rare in the universe, or perhaps it is just wishful thinking on our part. As mentioned earlier, just in the galaxy, there are hundreds of millions of planets that have the natural conditions to nurture life, so a reasonable speculation is that life has evolved on many planets, and even a number of planets have evolved intelligent life.

There are many rumors that Pluto is a terrible world, where the temperature is so low that no life can survive, and even if there is life, it may be some extreme virus, so how terrible and unusual is Pluto?

The mass of a star cannot grow indefinitely, it can only reach the "Eddington limit" at most, so beyond this threshold, it will soon "eject" the extra material

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.

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

Proxima, a slightly smaller red dwarf than Ross 508, has been frequently observed by astronomers as a giant flare in the past.