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

arstechnica.com

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

#221

Post by alephnerd »

laughing_man wrote: post #166
alephnerd wrote: post #98

Earlier quoted context omitted.

From a Defense perspective, it's acceptable if multiple ODC fails and you have to re-launch another one. This is why these are being treated as part of a mesh. These aren't supposed to be a commercial DC and are intended to be a mesh of multiple racks in orbit. The fact that the US, China, Russia, and India have already deployed ASATs means a Kessler effect if a question of when and not if .

The Russians put the first ASats up in the '70s. Their existence doesn't require use.

The difference is India and China had an orbital near-miss in 2024 [0] and both India and China now field ASATs.

It's a matter of time before Japan, SK, Iran, Israel, UAE, KSA, etc build similar capabilities.

[0] - https://www.bloomberg.com/news/articles/2025-09-22/india-pla...

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

#222

Post by cyberax »

lanstin wrote: post #204
cyberax wrote: post #174

Earlier quoted context omitted.

No. It'll stay in essentially the same orbit. During collision, some of the energy will be lost, so the fragments will necessarily have a lower orbit. The only thing that can accelerate fragments into a substantially higher orbit is the energy of elastic deformation of material during the explosion.

Can’t two solid object with equal kinetic energy collide in such a way that most of the energy goes into one of them, giving it a velocity that boosts its orbit while the other one has lower velocity and de-orbits? Or one object explode into two fragments, equal and opposite relative velocity, again pushing the one half into a higher orbit and de-orbiting the other half? (Honest question, math major, never took orbit…

> Can’t two solid object with equal kinetic energy collide in such a way that most of the energy goes into one of them, giving it a velocity that boosts its orbit while the other one has lower velocity and de-orbits?

Sure, you can. Imagine shooting a bullet into a tungsten cube. The cube will go into a higher orbit, and the bullet will bounce back (and maybe de-orbit).

But the kicker here is that for this to work, the bullet has to be in a _higher_ orbit than the cube initially. So the end result is still fewer objects in higher orbits.

Another option is momentum transfer via elastic deformation - you shoot a bullet into a 45-degree facet of that tungsten cube, and the bullet then ricochets into a higher orbit. It ultimately works by momentarily storing the energy of the projectile as a plastic deformation of the facet. So it can't accelerate more than a few small fragments.

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

#223

Post by kulahan »

avmich wrote: post #211
kulahan wrote: post #140

Earlier quoted context omitted.

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.

Full-flow staged combustion is a rather logical - and not even particularly useful, we're talking about small percentage points - extension of staged flow combustion, and staged combustion is a rather obvious change to open-cycle schema - and I'm hyperbolizing just a little bit here. Yes, it brings effects, and it's a cool technology. But saying that at least idea - or results - are fundamentally changing rocket engi…

There’s nothing logical about trying to make non-oxidizing metal that can handle thousands of degrees of temperature, hundreds of bars of pressure, and a nearly pure-oxygen environment? The US essentially made fun of the Soviets for even trying. If you think it’s logical, you don’t understand the tech at all. It’s a borderline miracle, let alone simply “logical”.

Literal rocket scientists spent decades and careers saying it was a waste of time, and random people with zero expertise try to downplay it. I’ll never understand being THIS cocky is a subject one has clearly never touched.

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

#224

Post by pfdietz »

amluto wrote: post #206
pfdietz wrote: post #134

Earlier quoted context omitted.

[flagged]

The numbers are easy to run, and the added power consumption is no joke. It’s even worse if your heat pump fails to achieve Carnot efficiency. Never mind that heat pumps can be heavy and may be completely destroyed by even a tiny micrometeoroid strike.

Yes, it needs more solar power. But solar panels should be much lighter than radiators, potentially vastly lighter. Even if Carnot efficiency is not approached there is plenty of room for improvement in the size of the radiators.

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

#225

Post by itsbczurstupid »

avmich wrote: post #210
Alive-in-2025 wrote: post #176

Earlier quoted context omitted.

Yeah, there's no solution for heat dissolution at this time. You can run a few cpus in space, you are a few seconds closer to the data to figure out something basic, but you cant do that much calculation. If you do much cpu intensive stuff, you just get hot quickly and you can't dissipate the heat. I'm sure new ways to cool down will be developed, but there's not even any experimental techniques, right?

ISS collects ~250 kW solar power. All of that needs eventually to be dissipated - the energy removed by communication radiowaves is small. ISS routinely handles this thermal question for decades. There is nothing magical with cooling in space. Just a different environment - a rather well studied already, we send satellites to space for some 70 years almost. Saying there is no solution is incorrect - we have options,…

[dead]

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

#226

Post by avmich »

kulahan wrote: post #223
avmich wrote: post #211

Earlier quoted context omitted.

Full-flow staged combustion is a rather logical - and not even particularly useful, we're talking about small percentage points - extension of staged flow combustion, and staged combustion is a rather obvious change to open-cycle schema - and I'm hyperbolizing just a little bit here. Yes, it brings effects, and it's a cool technology. But saying that at least idea - or results - are fundamentally changing rocket engi…

There’s nothing logical about trying to make non-oxidizing metal that can handle thousands of degrees of temperature, hundreds of bars of pressure, and a nearly pure-oxygen environment? The US essentially made fun of the Soviets for even trying. If you think it’s logical, you don’t understand the tech at all. It’s a borderline miracle, let alone simply “logical”. Literal rocket scientists spent decades and careers sa…

Soviets were world leaders in liquid fuel rocket engines. They used oxygen-rich preburners in e.g very successful line of engines starting with RD-170. It was possible decades ago. And no downplaying.

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

#227

Post by stickfigure »

laughing_man wrote: post #168
stickfigure wrote: post #43

Earlier quoted context omitted.

> There's a reason all modern silo based (and submarine) ICBMs are solids. Believe it or not, here in 2026, this is incorrect! Those crazy Russians: https://en.wikipedia.org/wiki/R-29RMU_Sineva https://en.wikipedia.org/wiki/R-29RMU2_Lajner UDMH + nitrogen tetroxide. I would not want to be a Russian submariner. For all sorts of reasons.

To be fair, while these missiles are still in service they're obsolete and are slated for retirement the coming decade.

The most recent started service in 2014. They may in fact be obsolete but not because they are old by soviet standards.

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

#228

Post by kulahan »

avmich wrote: post #226
kulahan wrote: post #223

Earlier quoted context omitted.

There’s nothing logical about trying to make non-oxidizing metal that can handle thousands of degrees of temperature, hundreds of bars of pressure, and a nearly pure-oxygen environment? The US essentially made fun of the Soviets for even trying. If you think it’s logical, you don’t understand the tech at all. It’s a borderline miracle, let alone simply “logical”. Literal rocket scientists spent decades and careers sa…

Soviets were world leaders in liquid fuel rocket engines. They used oxygen-rich preburners in e.g very successful line of engines starting with RD-170. It was possible decades ago. And no downplaying.

It doesn't have to be modern to be a miracle. The steam engine is one, too! I think this is still true of FFCS rockets, but maybe we're just wondering at different things in this world :)

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

#229

Post by onethought »

lightedman wrote: post #96
onethought wrote: post #75

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.

RL incorporated in the USA to gain launch licenses. They've been an American company for over a decade at this point.

Google incorporated in Ireland to gain tax benefits. They’ve been Irish ever since.

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

#230

Post by villgax »

GMoromisato wrote: post #93
villgax wrote: post #89

Earlier quoted context omitted.

you can imagine if they bother cracking landing back to re-use, it's KO for spacex

I can't tell if this is sarcasm, trolling, or delusion, so congrats, I guess. SpaceX might fail for any number of reasons in the next ten years, but I would bet a lot of money that it won't be because they got outcompeted by Skyroot.

Checks notes, the same exact line of commentary that exists for Spacex themselves
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