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India's first privately-developed rocket reaches orbit on debut launch

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Re: India's first privately-developed rocket reaches orbit on debut launch

#131
post #46

Regarding Indian private space sector, In addition to skyroot solid rocket, following are noteworthy Agnikul is planning to launch semi-cryo kerosene rocket pretty soon. Their engine is 3d printed and use electric pump fed 25kN small engine. Planning to launch 4 clustered engines as first stage and already did suborbital test, with some parachute splash down reusability claims. Astrobase is recent entrant. With decen…

>FFCS is called holy grail of liquid engines

Particularly for reusable liquid engines :)

Re: India's first privately-developed rocket reaches orbit on debut launch

#132

Earlier quoted context omitted.

> Ok, there are at least two bad assumptions there. > First, it assumes the radiator is at the same temperature as the GPU. But radiators become dramatically more effective as temperature increases, with radiated power increasing as the fourth power of absolute temperature. So a heat pump that drives the radiator at higher temperature could make the radiator far smaller. Carnot's theorem and refridgeration cycles rea…

> Carnot's theorem and refridgeration cycles rear their head. Your heat pump still needs power to pump heat uphill., negating any savings from a smaller radiator. And what happens when you shrink a radiator? It becomes a high temperature radiator, meaning the GPU must operate outside its operational tmperature of about 70 degrees C. Sorry, that's all nonsense. Yes, the extra power needs to be radiated. But the advant…

Again,

Smaller radiator = bigger heat pump + more batteries and solar panels

Satellites have a mass and power budgets. Your scheme only looks at temperature. If you want to build infinitely large AI Data satellites, go ahead.

Re: India's first privately-developed rocket reaches orbit on debut launch

#133

And with $160MM in funding at a $1.1B valuation? I don't know about their debt, but to get to LEO in 8 years on that little money is extremely impressive.

I think that's about the ballpark of what is required for a rocket of this size. SpaceX and RocketLab raised similar amounts prior to their first successful launches.

Re: India's first privately-developed rocket reaches orbit on debut launch

#134

Earlier quoted context omitted.

> Carnot's theorem and refridgeration cycles rear their head. Your heat pump still needs power to pump heat uphill., negating any savings from a smaller radiator. And what happens when you shrink a radiator? It becomes a high temperature radiator, meaning the GPU must operate outside its operational tmperature of about 70 degrees C. Sorry, that's all nonsense. Yes, the extra power needs to be radiated. But the advant…

Again, Smaller radiator = bigger heat pump + more batteries and solar panels Satellites have a mass and power budgets. Your scheme only looks at temperature. If you want to build infinitely large AI Data satellites, go ahead.

[flagged]

Re: India's first privately-developed rocket reaches orbit on debut launch

#135

Earlier quoted context omitted.

Maybe you need to let them know. They were founded in NZ by a NZer, they launch from NZ, their employees are NZers. Calling them a US company is equivalent to saying Google is Irish.

https://news.ycombinator.com/item?id=18427351 Design and manufacturing is in the los angeles region aerospace industry cluster. It's been a US company for the last 13 years. https://rocketlabcorp.com/updates/rocket-lab-makes-its-defen...

Design and manufacturing for the rocket part of their business is mainly split between Auckland and Los Angeles. Various sources say they have between 500 and 700 employees in NZ.

Earlier this year they acquired a new machining business in Auckland and are expanding capacity at their NZ launch site: https://rocketlabcorp.com/updates/rocket-lab-establishes-new...

Re: India's first privately-developed rocket reaches orbit on debut launch

#136

Earlier quoted context omitted.

This borders on science fiction. 88,000-and 1-million satellite clusters (as claimed in your link) are hard to take seriously, especially with the possibility of Kessler Syndrome. Also: 1. How do you cool your chips? Vacuum is a thermal insulator, so radiators are required to remove heat. nVidia (or even ASICs) require much and specialised cooling. 2. How does one radiation harden a H100? 3. I'm also seeing where TCO…

Explain to the class why Kessler Syndrome isn’t possible with large LEO constellations.

In a form of a question: does low earth orbit has big enough drag to be effectively do automatic cleanup every several years?

Re: India's first privately-developed rocket reaches orbit on debut launch

#137

Earlier quoted context omitted.

As raynier and pfdietz pointed out [0], the assumptions you are using aren't necessarily correct. [0] - https://news.ycombinator.com/item?id=49039873

Ah yes. The heat pump. My response: Carnot's theorem and refridgeration cycles rear their head. Your heat pump still needs power to pump heat uphill., negating any savings from a smaller radiator. And what happens when you shrink a radiator? It becomes a high temperature radiator, meaning the GPU must operate outside its operational tmperature of about 70 degrees C. So small radiator = big pump + extra solar panels a…

Yes, that was your response. It was a terrible and obviously invalid response, as I explained.

You never explained why the GPU temperature had to increase. Could you explain that now? The GPU would be on the cold side of the heat pump, not the hot side.

> Also, how do you deal with the added cost and complexity for the solar tracking mechanisms for the "edge-on-to-the-Sun" radiator?

We ignore that issue, because we were debunking a bad argument about "the laws of physics". The laws of physics say nothing about budgets or complexity.

Re: India's first privately-developed rocket reaches orbit on debut launch

#139

Earlier quoted context omitted.

Indian VC's don't really have the same appetite for deep tech as compared to America/Europe. R&D within Indian Enterprises is significantly less as compared to its peers. From what I know, its partially because of how taxation structures incentivize research as R&D tax breaks or similar don't particularly exist in India All of this makes founders more likely to move abroad where such research is more valued which mak…

Thank you for sharing that perspective; I'm from Eastern Europe and have had many Indian colleagues over the years (both in the EU and working remotely). I always wondered, given the super deep talent pool and many founders originally from India, why we don't see that many Indian companies on the global stage. I guess Eastern Europe is a bit similar (in the fact that it had a brain drain; although maybe less so since…

Indian companies just don’t have the contacts and background to access capital in the way that “yeh we went to school together” that opens more doors. It often seems like VC is designed to keep the idiot sons of the aristocracy occupied rather than being about building anything great.

Re: India's first privately-developed rocket reaches orbit on debut launch

#140

Earlier quoted context omitted.

Soviets definitely experimented with airborne CO2 lasers.

It just goes to show magical thinking isn't just an American thing.

I can’t imagine how inefficient a country would be if they tamped down all their magical thinking. FFCS, SMILE, and EUVL are all magical thinking if you ask me. Some of the craziest things humans have ever conceived of.
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