Bright Sword starts with the grenade flat.

Chapter 273 The real purpose of the Mars landing plan

In fact, Liu Xiu is not unfamiliar with the concept of helium flash at all, because Liu Xiu also watched Wandering Blue Star before traveling through time, so he was also very curious about the helium flash mentioned in the movie, so he checked some information to understand Helium flash is actually something that stars like the sun must experience.

What made Liu Xiu a little curious was how the alien's star-destroying bomb accelerated something that would have taken five or six billion years to happen so many times in a short period of time.

After all, according to estimates by Blue Star scientists, it will take about five billion years for the sun to evolve into a red giant, and about a billion years after the sun enters the red giant stage, a helium flash will occur.

Therefore, in other words, the helium flash will not occur until about six billion years later, but now Liu Xiu has determined that the Liangjian world he traveled through is actually the pre-world of Wandering Blue Star, and the helium flash will occur within a hundred years.

You must know that there is always a competition between two forces inside the normal sun. One of them is the gravity of the sun itself, which is directed from the outside in, and the other is the "radiation" produced by the nuclear fusion in the sun's core reaction zone. "pressure", its direction is from the inside out. The reason why the sun can be in a stable state now is actually that these two forces have reached a dynamic balance.

Specifically, if the "radiation pressure" has a slight upper hand, the sun will expand and the temperature of its core reaction zone will also decrease. The reaction rate of nuclear fusion is closely related to temperature. When the temperature decreases, the reaction rate will also decrease. will decrease, so the "radiation pressure" will decrease.

After that, gravity will slightly gain the upper hand, the sun will shrink, and the temperature of its core reaction zone will increase accordingly. When the temperature increases, the reaction rate of nuclear fusion will increase, and the "radiation pressure" will increase again. Slightly upper hand.

This battle between gravity and radiation is actually the origin of the solar cycle, and so on.

However, the sun cannot always maintain such a stable state. After all, the hydrogen in the sun is not infinite, and the hydrogen used as fusion fuel will eventually be used up.

What you need to know is that the temperature of the sun gradually increases from the outside to the inside. Only in the core reaction zone of the sun are there conditions for igniting hydrogen nuclear fusion. Due to the existence of "radiation pressure", matter in the outer layer of the sun cannot enter. The core reaction zone of the sun, so the sun can only consume hydrogen in its core reaction zone during the main sequence stage.

When the hydrogen in this region is exhausted, the sun's main sequence star stage will also terminate. At this time, the core region of the sun is almost entirely composed of helium, a by-product of hydrogen fusion.

But because the temperature inside the sun is not enough to ignite helium fusion at this time, the sun's interior loses the "radiation pressure" against gravity, and the sun continues to shrink.

The contraction of the sun means that the temperature inside it will become higher and higher. When the temperature inside the sun rises to a certain level, the hydrogen outside it that has never participated in nuclear fusion will undergo nuclear fusion in large quantities. , we can call it "shell nuclear fusion", so there is radiation pressure inside the sun again.

"Shell nuclear fusion" is much more intense than the sun's nuclear fusion in the main sequence stage. The radiation pressure it generates will prevail at this time. In this case, the volume of the sun will continue to expand, and then evolve into a A huge red giant star.

When the sun enters the red giant stage, its internal core temperature still does not reach the conditions required for helium fusion, so its interior will still continue to shrink. As the core fusion of the shell continues, a large amount of helium will continue to The consequence of the accumulation of earth is that the helium core composed of helium in the core of the sun is getting bigger and bigger, and the trend of shrinkage is becoming more and more obvious.

In this case, the helium nucleus will become denser and denser, and the temperature will become higher and higher. When the temperature reaches about 100 million degrees, helium nuclear fusion will be ignited. At this time, the material in the helium nucleus has already been compressed by gravity into degenerate helium. Only electron degeneracy pressure is used to resist gravity. Degenerate materials have an important feature, that is, their volume is not affected by temperature. , that is, it does not expand with heat or contract with cold, so this material cannot cool down through expansion. Therefore, once helium nuclear fusion starts, the energy released will cause the temperature of the helium nucleus to rise rapidly.

Compared with hydrogen nuclear fusion, the reaction rate of helium nuclear fusion is more sensitive to temperature. An increase in the temperature of helium nuclei will quickly trigger more helium to undergo nuclear fusion, which will cause the temperature of helium nuclei to further rise, thus forming A kind of positive feedback is created, so the reaction rate of helium nuclear fusion will increase sharply, causing thermal runaway nuclear fusion of helium nuclei, which is a chain reaction similar to a mushroom bomb.

However, this situation will not last long, because driven by huge energy, the material in the helium nucleus will soon exit the degenerate state. In this way, the helium nucleus can cool down through expansion, leading to thermal runaway nuclear fusion. It's over.

This is the so-called helium flash. Normally, a helium flash only lasts for a few seconds, but within these few seconds, the energy density it generates can exceed the hundreds of billions of stars produced by the sun in its main sequence stage. times, it can be seen that the power of helium flash is indeed quite amazing.

However, Liu Xiu's quantum clone did not find any specific information about star-destroying bombs in the alien spacecraft's computer. It only knew that the instructions given by the alien civilization to the artificial intelligence of this spacecraft were that if there were nuclear-level weapons on the living planet, reaction, then immediately throw the star-destroying bomb carried on the spacecraft into the sun.

Therefore, although Liu Xiu has obtained the information about this alien spacecraft, to be honest, how much information can be put on an unmanned accelerating spacecraft is not a scientific research spacecraft.

This is like picking up a thousand-dollar drone on the battlefield of Big Bear and trying to get information about the entire human civilization from this drone. Is this possible?
Therefore, after Liu Xiu compared this alien spacecraft to human drones, Liu Xiu did not have much hope for this alien unmanned spacecraft.

However, if some key technologies can be reproduced, it will still be of great help to Wandering Blue Star in the future.

For example, the controllable nuclear fusion reactor on this unmanned spacecraft, and the curvature engine technology that allows this unmanned spacecraft to fly faster than light.

As long as he has these two technologies, even if the planetary engine cannot be built and other crops on Blue Star do not cooperate, Liu Xiu can still build a large spaceship to take away the humans on his side.

After all, Liu Xiu had also seen the Wandering Blue Star II, and he was very, very disgusted with that kind of sabotage. A good space elevator was destroyed like this, and so many people died.

Therefore, after Liu Xiu found out at the beginning that it was Wandering Blue Star, he was making second-hand preparations. This second-hand preparation was to leave aside other crops and only work on Liu Xiu's side, which would reduce a lot of trouble.

It is exactly like this that Liu Xiucai will continue to promote the Mars immigration plan. After all, the mass of Mars is only one-ninth of Blue Star, so it is much easier to push Mars than to push Blue Star. The original more than 10,000 planetary engines It would only take more than a thousand to put it on Mars.

(End of this chapter)