Extraterrestrial

The energy released by the sun's nuclear fusion reaction, in addition to making the sun shine and heat, there is an important role, that is, to resist its own gravity

Whichever way you look at it, humans cannot be the only intelligent creatures in the universe. As far as we know, the universe has existed for at least tens of billions of years, so a reasonable speculation is that there is probably an advanced civilization in the universe that is hundreds of millions or even billions of years ahead of humans, and if that is the case, their level of technology is something that we humans simply cannot imagine.

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.

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"

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

If you are so close to the main star in the solar system, life simply cannot survive

The milky way is a huge galaxy with hundreds of billions of stars, and the sun is just one of the less prominent stars that, along with many other stars in the galaxy, orbits the centre of the galaxy.

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

In the photos returned from the rover, we see Mars as a desolate world without a trace of life. Although Mars looks desolate and dry, there are many people who believe that Mars may become a second home for us humans

This exoplanet, known as TOI 700d, is about 101.5 light years away from our Earth, which means that even if we were to travel to this exoplanet in a light-speed spacecraft, it would take at least 101.5 years of flight to reach it, so it is very far away