Finally, I used the EM engine to send off the leader of the work-free propulsion faction.

Zhang Xingyang finally breathed a sigh of relief.

In fact, the shortcomings of the EM engine, Zhang Xingyang did not say it explicitly just now.

That is, the thrust output is less than that of the Hall thruster.

Even the more mature EM engine in later generations has only about half the thrust of the Hall thruster of the same class compared to the Hall thruster of the same class.

This means that the EM engine accelerates and decelerates twice as long as the same Hall thruster for the same space range.

Of course, the Hall thruster itself has a lot of shortcomings.

Hall thrusters, for example, need to use xenon as fuel.

Xenon is actually very expensive on Earth.

And it is also more difficult to prepare.

In fact, in the future space age, it is more likely to be used for industrial propulsion.

For example, a Proxima Centauri probe was launched in 2150 with an EM engine.

It was the most advanced EM engine at the time, but the thrust was still very small, producing only 122.2 grams of thrust.

It is only capable of providing the detector with an acceleration of 0.001 mm/s per second.

It would take about five years to accelerate the probe to the solar system's escape velocity of 16.6 km/s.

And that's just the time to accelerate.

"Xingyang, what do you think the future of working fluid propulsion will look like?"

On the train back to the Rocket Research Institute on the night of the meeting, Geng Bo asked Zhang Xingyang.

"The future!"

Zhang Xingyang recalled the space battleships he had seen in his life.

"In the future, the biggest difference between the working fluid and the current one will be the change of working fluid due to the change of the engine."

"What do you mean, tell me more about it?"

Geng Bo also came with a lot of interest.

"First of all, let me ask you, what do you think will be the future of space engine?"

Geng Bo himself had thought about this question before when he was bored.

"I don't think the rocket method we use now should be eliminated."

"But there should be a lot more other space engines."

Geng Bo had a good idea.

In the next one or two hundred years, rockets, as a mode of interstellar transportation, have not been eliminated, and have even been developed.

It's as if the bicycle wasn't obsolete for hundreds of years after the invention of the automobile.

Each vehicle has its own use case.

The same is true of the role of rockets.

On a planet with a thick atmosphere, it was applied to the era before Zhang Xingyang crossed through the planet's atmosphere through rocket launches.

However, at that time, rocket launches were not as cumbersome as they are now.

Rather, it is like a bus, which frequently travels between the ground and space.

"If we can do nuclear fusion, fusion working fluid propulsion should also be feasible."

Geng Bo was still a little unsure when he talked about this time.

After all, nuclear fusion has a saying that it lasts forever for 50 years.

No one knows exactly when this invention will be completed, which could change the course of human history.

"There's a real chance that this will be the propulsion method for large spaceships in the future."

Zhang Xingyang first affirmed Geng Bo's idea.

"Nuclear fusion propulsion has a lot of advantages."

"The first is fusion fuel, which is not lacking on many planets in the solar system."

"Just above the moon, we have helium-3 that we can use for tens of thousands of years."

"The second point is that nuclear fusion itself is capable of producing a large number of high-temperature plasmas, and these plasmas are capable of producing extremely powerful thrust."

Zhang Xingyang said the propulsion method of the fusion propulsion spacecraft.

Nuclear fusion produces extremely hot plasma that is difficult to utilize directly.

On the ground, it's a little better, and it's able to generate electricity by boiling water constantly.

But in space, this path doesn't work.

Because there is no way to transfer heat by convection in space, there is no medium for heat conduction.

These plasma, which is so hot that it almost reaches the core temperature of the sun, can only be expelled as a propulsion exhaust gas.

"That's quite interesting, now everyone thinks that if nuclear fusion is achieved, it should rely on generating electricity and then generating radiant light pressure to drive the spacecraft."

After listening to Zhang Xingyang's statement, Geng Bo found it very interesting.

At present, whether in the scientific literature or in various fantasy works, there seems to be little mention of this method of direct use of exhaust gases for propulsion.

"In fact, there may be more advantages to another method of propulsion than fusion propulsion, but it is also too difficult."

Zhang Xingyang continued to talk about his thoughts when Geng Bo sighed.

"That's antimatter propulsion."

"Antimatter?"

Geng Bo was also a little surprised at this time.

If we talk about nuclear fusion just now, there is still a saying that it will last forever for 50 years.

At this time, antimatter is basically still a science fiction thing.

Over the past few years, antimatter has been the jewel of physics.

There is an endless stream of research on antimatter.

It is not only the first time that the artificial manufacture of antimatter has been completed, but also tens of thousands of low-energy antihydrogen atoms have been mass-produced.

However, in the laboratory, a lot of antimatter is produced.

But at this time, the research on antimatter was still very rude.

There is no precedent for being able to conduct practical research.

"You should also know that compared to the energy utilization rate of traditional methods, even nuclear fusion is actually not 100 percent."

"But antimatter is different, when the positive and antimatter are extinguished, the energy completely converts its own mass into energy."

Zhang Xingyang went on to explain the use of antimatter in starships.

"Achieving 100 percent energy utilization allows us to achieve the efficiency of fusion propulsion even with only one-third of the fuel."

Although Zhang Xingyang described it well, Geng Bo still had a lot of questions.

"But antimatter production is a problem, isn't it?"

"We're still making all this antimatter in the lab, and it's still too difficult to make antimatter in large quantities."

"It's not as troublesome as you think."

Zhang Xingyang didn't care about this problem.

"We don't have to prepare it in the lab at all."

"In the solar wind, there are a lot of antihydrogen atoms."

"We can deploy a large number of special magnetic field cages outside the solar orbit to store these antihydrogen atoms from the solar wind."

Zhang Xingyang smiled and said:

"Have you ever seen a village in a small river or creek with a fish cage?"

"Put the cage in the water, just wait quietly and you can go to collect the fish and shrimp the next day."

"The reason is the same, after placing the special magnetic field cage, we only need to regularly harvest the antihydrogen atoms." (End of chapter)