Brilliant Pebbles was a non-nuclear system of satellite-based, watermelon-sized,[21] mini-missiles designed to use a high-velocity kinetic warhead.[22] It was designed to operate in conjunction with the Brilliant Eyes sensor system and would have detected and destroyed missiles without any external guidance. The project was conceived in November 1986.[23]
John H. Nuckolls, director of Lawrence Livermore National Laboratory from 1988 to 1994, described the system as “The crowning achievement of the Strategic Defense Initiative”. The technologies developed for SDI were used in numerous later projects. For example, the sensors and cameras that were developed for Brilliant Pebbles became components of the Clementine mission and SDI technologies may also have a role in future missile defense efforts.[24]
Though regarded as one of the most capable SDI systems, the Brilliant Pebbles program was canceled in 1994 by the BMDO.[25] However, it is being reevaluated for possible future use by the MDA.
skyblue said:I’m surprised there is so little interest in Brilliant Pebbles and push to resurrect the program.
It always seemed to me like an 80’s ideas that belongs in the 2020s: clouds of small, smart cheap components, machine learning, automation, high level of decentralization. If SpaceX, Blue Origin and the crowd of other new/old space fulfill expectations to bring down launch costs dramatically, it’ll be much more affordable, and imaginable to put up the thousands of interceptor satellites needed. Miniaturization and A.I. has vastly improved, hugely so since the 80s when Brilliant Pebbles was conceived. Surely we can build much smaller, cheaper and thus populous interceptors? This has been a fashionable trend in satellite technology: SmallSats, CubeSats, Elon Musks’s humungous internet satellite constellation.
That wouldn't be true. C&C would be highly centralized.high level of decentralization.
Those KKV deals astounded me how rock steady they were in hovering over those nets—making the craft of Armadillo and friends look like wobbly drunks:
skyblue said:I’m surprised there is so little interest in Brilliant Pebbles and push to resurrect the program.
It always seemed to me like an 80’s ideas that belongs in the 2020s: clouds of small, smart cheap components, machine learning, automation, high level of decentralization. If SpaceX, Blue Origin and the crowd of other new/old space fulfill expectations to bring down launch costs dramatically, it’ll be much more affordable, and imaginable to put up the thousands of interceptor satellites needed. Miniaturization and A.I. has vastly improved, hugely so since the 80s when Brilliant Pebbles was conceived. Surely we can build much smaller, cheaper and thus populous interceptors? This has been a fashionable trend in satellite technology: SmallSats, CubeSats, Elon Musks’s humungous internet satellite constellation.
I noticed the strategic use of "if" in your scenario...
Yeah, things might be a lot cheaper in this theoretical future. But it's never going to be really cheap. Take lots of relatively cheap components and now try to integrate them all. The integration requires a lot of software effort and a lot of people looking over all of that. It's not easy. And it won't be cheap.
Plus, we don't even know if this would work. It requires a lot of spacecraft covering a lot of territory and all connected into a warning and tracking system that might not behave as advertised.
It wasn't used for Mars probes.
I have no doubt that the KKV tech can be made even cheaper with additive manufacturing. Clementine used that tech…and I would not be surprised to find it behind the tech that allowed Delta II Mars probes that also had to be small.
Not really and everything is not in place. It would take more ground sites and more tracking spacecraft to enable it.
Whether a Ku/Ka-band radio transceiver is cheaper than a small micro rocket with a strap-down uncooled IIR seeker or not is an open question I suppose. Given that everyone else exists between NORAD, the various BMEWS sites, PAVE PAWS, LRDR, and Fort Greely for orbital engagements, providing Delta 9 actual battle systems is somewhat trivial at this point; so SDI at least has everything in place except the actual interceptors now.
Through that kinda falls down itself once you remember something.Brilliant pebbles falls down because you only have a very limited number of pebbles in the right place at the right time.
Pebbles don't have that much capacity to manoeuvre to other places, and once one patch intercepts a missile of two, the rest get through. KKVs works because the missiles they're on deliver them to the correct spot, with Brilliant Pebbles you have lots of KKVs in the wrong spot and very few in range of the launch trajectories at the right time. You'd be better off saving the rockets and rocket fuel to fire them all up to the right spot at the right time.Through that kinda falls down itself once you remember something.
Starlink has over 3000 satellites in the sky at the mount. Right where the Pebbles were to sit and are triple in size. And the math to properly stop the Soviets said you needed bout 10k. With 4,600 being enough to do limited strike stopping like what China or Korea can do.
The Full Pebbles shield is possible right now, just need to upgrade the designs and launch them. Will deal with far less red tape as well.
And I honestly make them bigger as well, just enough to allow them to double as a low level comm retransmit satellite for ground forces.
Yes, assuming the electronics on the KKV can withstand the many thousands of g it will experience during firing, and the gun is powerful enough.A railgun might be of use to fire KKVs perhaps? Dual use cubesat-KKVs fired to celestial bodies at end of life?
no, it isn't. There isn't the detection, tracking, command and control systems to manage them.
The Full Pebbles shield is possible right now, just need to upgrade the designs and launch them. Will deal with far less red tape as well.
And I honestly make them bigger as well, just enough to allow them to double as a low level comm retransmit satellite for ground forces.
Yes but at the same time BPs have far fewer targets to hit since they go after missiles before they can deploy warheads/penaids, while KKVs go after the warheads themselves.Pebbles don't have that much capacity to manoeuvre to other places, and once one patch intercepts a missile of two, the rest get through. KKVs works because the missiles they're on deliver them to the correct spot, with Brilliant Pebbles you have lots of KKVs in the wrong spot and very few in range of the launch trajectories at the right time. You'd be better off saving the rockets and rocket fuel to fire them all up to the right spot at the right time.Through that kinda falls down itself once you remember something.
Starlink has over 3000 satellites in the sky at the mount. Right where the Pebbles were to sit and are triple in size. And the math to properly stop the Soviets said you needed bout 10k. With 4,600 being enough to do limited strike stopping like what China or Korea can do.
The Full Pebbles shield is possible right now, just need to upgrade the designs and launch them. Will deal with far less red tape as well.
And I honestly make them bigger as well, just enough to allow them to double as a low level comm retransmit satellite for ground forces.
True but given the amount of rockets required to put thousands up there (4063 in the case of the SDI proposal), and the fact only a few dozen will be in the right place at the right time, you've wasted ~4000 launches. On the other hand if you spent the same money on interceptors, you'd have several thousand, so even with a 10% Pk you'd be two orders of magnitude better off. Additionally, we don't even have 10 warhead missiles anymore under the latest iteration of START, 4 max, so even that advantage is diminished. Equally, brilliant pebbles won't work on HGVs, which travel endo-atmospheric. To make space interceptors worthwhile, you need a propelled direct energy system that can hit ICBMs at launch and throughout any flight profile. It would also have dual use applications.Yes but at the same time BPs have far fewer targets to hit since they go after missiles before they can deploy warheads/penaids, while KKVs go after the warheads themselves.
Thats incorrect, under New START you can put as many warheads on a booster as you want.True but given the amount of rockets required to put thousands up there (4063 in the case of the SDI proposal), and the fact only a few dozen will be in the right place at the right time, you've wasted ~4000 launches. On the other hand if you spent the same money on interceptors, you'd have several thousand, so even with a 10% Pk you'd be two orders of magnitude better off. Additionally, we don't even have 10 warhead missiles anymore under the latest iteration of START, 4 max, so even that advantage is diminished. Equally, brilliant pebbles won't work on HGVs, which travel endo-atmospheric. To make space interceptors worthwhile, you need a propelled direct energy system that can hit ICBMs at launch and throughout any flight profile. It would also have dual use applications.Yes but at the same time BPs have far fewer targets to hit since they go after missiles before they can deploy warheads/penaids, while KKVs go after the warheads themselves.
True, that's new, but I don't think it changes the calculus enough to change things. Penaids are fairly easy to discriminate with modern dual-polarised radars.Thats incorrect, under New START you can put as many warheads on a booster as you want.
Boost phase intercept is also easier, since you have a big, slow, soft, bright target without penaids, compared to trying to hit a small fast, hardened warhead amidst a cloud of penaids.
Second, LRDR is “a dual-polarized, dual-range capability radar.” Marshall wouldn’t go into details, but the term “dual-polarized” is used in open literature to describe cutting-edge civilian weather radars, which are better at telling the difference between, say, rain, snow, and hail, and can even measure the size of the hailstones as they come down.
Not really and everything is not in place. It would take more ground sites and more tracking spacecraft to enable it.
Whether a Ku/Ka-band radio transceiver is cheaper than a small micro rocket with a strap-down uncooled IIR seeker or not is an open question I suppose. Given that everyone else exists between NORAD, the various BMEWS sites, PAVE PAWS, LRDR, and Fort Greely for orbital engagements, providing Delta 9 actual battle systems is somewhat trivial at this point; so SDI at least has everything in place except the actual interceptors now.
True but given the amount of rockets required to put thousands up there (4063 in the case of the SDI proposal), and the fact only a few dozen will be in the right place at the right time, you've wasted ~4000 launches.
As a counter you could have a multi-KKV interceptor though.You would launch multiple interceptors per launch, just as the constellation operators launch 50 satellites per. A lot of the work to make the system feasible was about cutting the mass per interceptor, to reduce launch costs. The actual numbers are afaik still very classified, but the wet mass of an interceptor was definitely expected to be less than a ton. On Starship, that would mean >100 interceptors per launch. And that was with 90's sensors and computers, I'd bet that they could be made even smaller today.
And with a good trajectory planning, a lot more than a few dozen will be in place to intercept. The work from the 90s estimated that 10% of the entire constellation would be able to make boost-phase intercepts against a mass launch. Another 5% or so would be able to try to make (much lower Pk) late-stage intercepts when any surviving missiles come down.
Not that I'm saying that brilliant pebbles are necessarily a good idea, just that the common arguments against them are no longer relevant. Even without Starship, with F9 routinely launching 17t in reusable mode to mid-inclination orbit, it's now fair to say that the launch costs are irrelevant. Everything else in the program is going to cost so much more, that if you do it you can hide the launch costs in the rounding errors.