China's Space Program Thread II

[Blitzo]

The jury's out on reusable rockets. There are some commentators that are saying that SpaceX will be bankrupt in 3 to 5 years given the fundamentals. I tend to agree with their analysis.

The jury is technically put but recent tans current track records are such that the starting gun has been shot and that every player needs to at least compete, because if it turns out that reusable rockets are actually viable then not competing means you will be devastatingly behind.

The financial state of SpaceX is not relevant to this discussion and it is safer for everyone to operate with the assumption that they will survive and be successful.

 

[Wrought]

The jury's out on reusable rockets. There are some commentators that are saying that SpaceX will be bankrupt in 3 to 5 years given the fundamentals. I tend to agree with their analysis.

Even if the business model of SpaceX turns out to be not commercially viable, that doesn't have any bearing on the obvious strategic utility of its launch capacity. The government is not obligated to make a profit.

 

[jli88]

Even if the business model of SpaceX turns out to be not commercially viable, that doesn't have any bearing on the obvious strategic utility of its launch capacity. The government is not obligated to make a profit.

SpaceX is going to be solvent for a long time, it has been so successful, that there are more than enough investors ready to write as many checks as it wants. Heck, Jeff Bezos would probably give Musk as much money as he wants to hand over SpaceX.

About long term business potential, the military business itself is more than enough to sustain it if it were to come to that. US is turning incredibly fast towards cheaper, attritable systems. You can shoot down one satellite in GEO, but you can't shoot down 5000 of those in LEO.

SpaceX already provides valuable communication capability in a distributed manner, already proven in Ukraine. It is also launching a LEO military constellation. (Was revealed recently)

Apart from that SpaceX has an actual business proposition in the US where countryside internet connectivity is just horrible, and building physical infrastructure is prohibitively expensive. Same business proposition applies everywhere. Unit costs will come down as the constellation is built, the users increase, and the gear gets commercialized and scaled.

 

[gelgoog]

About long term business potential, the military business itself is more than enough to sustain it if it were to come to that. US is turning incredibly fast towards cheaper, attritable systems. You can shoot down one satellite in GEO, but you can't shoot down 5000 of those in LEO.

I guess you never heard of Polyus/Skif.

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The Soviets designed it to shoot down US Strategic Defense Initiative satellites.
Today the Russians and Chinese have small parasite satellites which can be launched and either knock other satellites out of orbit or disable them.

 

[jli88]

I guess you never heard of Polyus/Skif.

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The Soviets designed it to shoot down US Strategic Defense Initiative satellites.
Today the Russians and Chinese have small parasite satellites which can be launched and either knock other satellites out of orbit or disable them.

Not buying it, lasers aren't powerful enough afaik. (Maybe more resources can convince me otherwise). Lasers are okay to temporarily blind optical sensors, but we are talking about communication satellites. Even if you were to have a space based laser, and say you place 10 of those, they are again centralized and easier to shoot down that shooting down 10000 satellites in LEO which can be rapidly replaced.

 

[gelgoog]

It used a 1 megawatt laser. It is like 10-20x more powerful than the combat lasers typically used today. And there is no atmosphere in space to attenuate the laser.

 

[anzha]

It used a 1 megawatt laser. It is like 10x more powerful than the combat lasers typically used today. And there is no atmosphere in space to attenuate the laser.

MIRACL in the US was the same class. Weapons of that power did exist, but had large drawbacks. So much so, they were not pursued further. THEL was MIRACL's little sister and even that had too many issues.

That said, the energy levels of modern solid state lasers will soon catch up.

And...we are getting off topic. This is the CHINA space thread.

 

[gelgoog]

It used a carbon dioxide laser. This is a gas laser. To fire more shots you basically just need to input more electricity.
The only complication is that you would still have recoil and heat to counter and dissipate.
Systems like the US MIRACL were chemical lasers. You would mix chemicals together to generate laser light, consuming the chemicals in the process. And these chemicals are typically toxic corrosive chemicals like chlorine and fluorine.

The Soviets were ahead of the US in laser technology during the Cold War period.

 

[anzha]

The Soviets were ahead of the US in laser technology during the Cold War period.

Perhaps another thread than this one would be the place to discuss this. Again, China Space thread.

The US abandoned CO2 lasers for weight reasons: polyus was 95 tons vs the planned launch of Alpha (MIRACL's space based cousin) on the US Shuttle. If the US had kept the Saturn V, then different decisions might have been made.

However, again, China space thread.

 

[iantsai]

北京时间5月8日10时12分，在北京航天飞行控制中心的精确控制下，嫦娥六号探测器成功实施近月制动，顺利进入环月轨道飞行。

近月制动是嫦娥六号探测器在飞行过程中的一次关键轨道控制。嫦娥六号探测器飞临月球附近时，实施“刹车”制动，使其相对速度低于月球逃逸速度，从而被月球引力捕获，实现绕月飞行。

后续，在鹊桥二号中继星的支持下，嫦娥六号探测器将调整环月轨道高度和倾角，择机实施轨道器返回器组合体与着陆器上升器组合体分离，之后，着陆器上升器组合体实施月球背面南极-艾特肯盆地软着陆，按计划开展月球背面采样返回任务。

Chang'E-6 braked and entered the lunar orbit successfully on 10:12 UTC+8 today.

With the support of Queqiao-2 relay satellite, Chang'e-6 will adjust the altitude and inclination of its orbit and separate the orbiter-retuner assembly and the lander-ascender assembly.

The lander-ascender assembly will then soft-land in the Antarctic-Aitken Basin and conduct the sample return mission.