"universe"

A rigorous discussion of the unknown is not possible, so it is necessary to narrow down the universe we are discussing to only the universe we can see

After the sun evolves into a red giant, the hydrogen in its core is almost completely fused into helium, so the nuclear fusion inside the sun stops, after which the sun loses its internal radiation pressure and continues to collapse, leading to a constant increase in temperature and pressure in its core, while the helium in the central region of the sun is gradually compressed into the condensed state.

Everything we can see in the universe has an internal structure and they are all made up of smaller matter, so what is the smallest matter in the universe?

For humans, the universe is too dimensional for us to see the details of its depths for the time being

In the past days, scientists have been working on the study of meteorites, and as the research continues, there is more and more evidence that life should originate from outer space

How exactly did such a complex life emerge on Earth? This is a great mystery to modern humans, but we are almost certain that the "birth of life" is a process that has a very small probability of occurring.

Scientists using modern observation equipment have determined the size, position, distance and other data of most of the objects in our galaxy

Further research shows that this mysterious force accounts for 68.3% of the total mass energy of the universe, and it is because of this that it is able to overcome gravity and become the dominant force controlling the operation of the universe

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