Chapter 317: Gravitational slingshot concept

The performance of polyimide can be said to be very excellent. It can work very well in the range of minus 200-300 degrees, and its mechanical properties are excellent. It is currently the organic high-speed fiber that can be used by light sail and has the best overall performance. One of the molecular materials.
At the same time, polyimide has a very good property, that is, it is very light.
According to Newton's second law, it can be known that under the action of the same magnitude of force, the lighter the object will obtain the greater acceleration, and the easier it will be.
Especially when everyone hopes that the spacecraft can reach close to the speed of light, the possibility of mass increase under the effect of relativity must also be considered.
Therefore, even if the quality of the solar sail is reduced by a small amount, the benefits we can obtain are very huge. This is why the scientific research personnel make the solar sail so thin.
In Ye Fan's black technology system, although there is a lot of cosmic engine technology, whether it is a curvature engine or an engine that travels at super-light speed, it is not human's current technological level that can be played.
Therefore, the solar sail is an important means for human beings to fly out of the solar system and even long-range interstellar navigation.
The sunlight is constantly radiating outwards, so it is indeed difficult to get close to Mercury. Ye Fan’s initial plan is to install solar sails on the mining spacecraft and let the mining spacecraft fly directly to Jupiter after reaching a very high speed. .
Then use Jupiter's gravity, also known as the "gravitational slingshot," to directly throw the mining spacecraft to the position of Mercury.
Planets are not stationary. They carry huge angular momentum in both rotation and revolution. In the overall angular momentum of the solar system, the sun's own angular momentum accounts for only 2%, and the other 98% of the angular momentum is controlled by the surrounding The sun in the hands of the stars.
When the mining spacecraft cuts into the planet's orbit, it also gets a part of the planet's angular momentum, and the transferred angular momentum is reflected in the speed change when the spacecraft flies out of the planet's gravitational field.
Taking the sun as the reference object, the speed of the spacecraft flying out of the planet at this time not only changes the direction, but also increases the size.
Because according to the law of conservation of energy, the increased kinetic energy of the spacecraft is also the reduced kinetic energy of the planet. It is just that the kinetic energy of the planet is too large, and the kinetic energy of a small spacecraft is just a fraction of the difference. What will affect the planet.
It is as if we use wind power to generate energy from the flow of the air, without worrying that the wind will stop because of this.
Therefore, the gravitational slingshot and the solar sail, whether it is sailing in the solar system or interstellar sailing after leaving the solar system, are feasible.
The electromagnetic propulsion engine, although it can be propelled in a vacuum, but the fatal disadvantage of this engine is that it consumes a lot of power.
The power consumption of this thing in a vacuum is even more than fifty times larger than that of an ion engine.
Therefore, electric propulsion engines require a lot of electric power. However, if the electric power consumption of electric propulsion engines is to be met, it is inevitable to make the battery bigger. After the battery is bigger, the spacecraft will also increase in size.
In this way, you will fall into the previous "paradox" again.
So this is why Ye Fan would engage in solar sails.
Unless Ye Fan can build a spacecraft of the size that accommodates a heavy nuclear fusion reactor, and when he is sailing, he constantly excavates ore from the surrounding asteroids to supplement energy, and then drives the electric propulsion engine to navigate the stars.
However, before the formal integration of global resources, to build such a large spaceship is tantamount to a dream.
Although the polyimide that composes the solar sail is already very light, the system exchange technology shows that polyimide is not the best choice.
"Look, this is the difference between our solar sails and foreign solar sails. We discovered a new material, also known as a solar sail weapon."
"Graphene."
Ye Fan's words fell, and the audience was in an uproar.
You know that graphene is not uncommon, but most people associate it with batteries. After all, graphene can indeed increase the capacity of batteries.
However, if graphene is simply used to increase power storage, it would be too wasteful.
"This is our latest graphene. Its microstructure is that carbon atoms are connected to each other in a hexagonal shape, so its performance will be very amazing."
Later, Ye Fan sent another piece of research data to the holographic projection.
Su Ying also nodded at this time. Although she is not a materials scientist, she is not unheard of graphene.
"This kind of material is indeed possible. After all, even if we have the corresponding technology, all materials can be compressed to the atomic level, but their strength cannot be guaranteed.
But in the case of graphene, it seems that there is no such concern. Its microstructure allows it to be very strong on the atomic scale~EbookFREE.me~ When designing spacecraft, we also investigated about graphene. Data, so I also know some things about graphene. "Su Ying said.
"Well, regarding this kind of graphene, a foreign research team has created a miniature light sail with a diameter of only three millimeters but a mass of less than a quarter of a gram.
Then they placed this light sail in a microgravity environment and irradiated it with laser irradiators ranging from 0.1 watt to 1 watt to test its performance. "
Subsequently, Ye Fan uploaded another picture, which shows the latest graphene micro-sail created by SCALE Nanotechnology.
The final experimental results showed that the performance of this light sail was very good and achieved the expected effect.
"Of course, they are limited by the level of technology, and they can only do this at the moment. It is difficult for them to make a big breakthrough in a short period of time, but our Datang Technology,
However, it is possible to create an atomic-thick solar sail, which is much more advanced than that of foreigners. Due to production and practical application issues, a graphene solar sail with a diameter of more than one kilometer is still impossible.
However, we are working on a solar sail with a diameter of 300 meters and a width of 200 meters. Its mass is not even one kilogram, but it is limited by area, so even if it is folded, it takes up a lot of space. "
Ye Fan projected another graphene solar sail on the desktop. The elites present were all surprised by Datang Technology's strong scientific research capabilities and strong industrial capabilities.
Not only did the lithography machine come out, but also atomic-level graphene. If the latter can be realized, then humans really have the ability to take the first step in interstellar navigation.