Oh, Great

This bothers me a lot. Not because SpaceX is not qualified to do this, but because it shows that the military/industrial complex has gotten their nose under the tent. Once they become one of your biggest customers, then they can subtly threaten your bottom line and ask for “favors”

Vice reports: [vice]

The Department of Defence’s Space Development Agency (SDA) awarded Elon Musk’s SpaceX a $149 million contract to build four missile tracking satellites. 

“The satellites will be able to provide missile tracking data for hypersonic glide vehicles and the next generation of advanced missile threats,” Derek Tournear, the director of the Space Development Agency, said in a press release. SpaceX will build and deliver four of its Starlink satellites which the Pentagon said it will fit with special sensors to allow them to track missiles, including nuke-bearing Intercontinental Ballistic Missiles and hypersonic glide vehicles.

That’s worrisome. For one thing, it means that the entire Starlink satellite cloud is now a civilian target in a military incident. In the event of a full-up nuclear exchange, nothing will matter, but in the meantime it’ll serve as another way of monitoring other nations to make sure they’re not getting up to what we’re getting up to.

Call it “Vela 2.0” Most people don’t know what the Vela satellite system is/was (I assume there is something like it still in place) – the Vela satellites were sensitive measuring devices that looked for the distinctive electronic “pop” of a nuclear weapon going off. The sensors were called, appropriately, “bhangmeters.” The satellites were able to detect a single pop from a fission bomb, or the double pop-snap of a two-stage fusion device. It’s the Vela satellites that inspired my “Another short story about nuclear war” [stderr] – there are other things in the universe that have a similar pulse but they’re supernovas and happen on a different time-scale.

The Vela satellites are part of an interesting story: in 1979 one of the Vela satellites detected a double pulse near South Africa. There was some scrambling in the intelligence community and at the policy levels to figure out who had fired a nuke test and whose program was sufficiently advanced. People who watch this stuff, myself included, concluded it was probably Israel which, at the time, was making nuclear technology trades with fellow apartheid government in South Africa. At that time, South Africa had a nuclear program, which they later shut down because of international pressure, its lack of success, its cost, and – more importantly – it was realized that South Africa’s threats were internal and nuclear weapons would not help with them.

A recent piece in Foreign Policy gives a detailed account of the “Vela Incident” and reveals additional sources that point the finger at Israel. Realistically, everyone knew it – its just that the US would have been revealed for hypocrisy by continuing to ignore Israel’s nuclear program while simultaneously strong-arming other nations about theirs. The situation remains unchanged since 1979: Israel is still an “undeclared” nuclear power in spite of widespread documentation of their program (Mordecai Vanunu’s detailed descriptions of the refinement plant at Dimona, etc) and the US is still ruthlessly turning the screws on Iran and anyone else that they can point at and claim “they have a nuclear program!” The article in Foreign Policy reads like a novel, it’s really good and interesting though admittedly it’s an account that’s mostly interesting to a specialist.

Shortly before sunrise on Sept. 22, 1979, a U.S. surveillance satellite known as Vela 6911 recorded an unusual double flash as it orbited the earth above the South Atlantic. At Patrick Air Force Base in Florida, where it was still nighttime on Sept. 21, the staff in charge of monitoring the satellite’s transmissions saw the unmistakable pattern produced by a nuclear explosion – something U.S. satellites had detected on dozens of previous occasions in the wake of nuclear tests. The Air Force base issued an alert overnight, and President Jimmy Carter quickly called a meeting in the White House Situation Room the next day.

Nuclear proliferation was just one of the Carter administration’s headaches in late 1979. The president was dealing with a slew of foreign-policy dilemmas, including the build-up to what would become the Iran hostage crisis. Carter was also preparing for a reelection campaign in which he had hoped to showcase his foreign-policy successes, from brokering Israeli-Egyptian peace to successful arms control talks with Moscow. The possibility that Israel or South Africa, which had deep clandestine defense ties at the time, had tested a nuclear weapon threatened to tarnish that legacy. And the fact that South Africa’s own nuclear weapons program, which the Carter administration was seeking to stop, was not yetsufficiently advanced to test such a weapon left just one prime suspect: Israel. Leading figures within the administration were therefore keen to bury the story and put forward alternative explanations.

Plus ça change, neh? I like how the article dances delicately past the fact that the Carter administration was trying to pass their foreign policy off as successful because of an election. I’m slowly coming to realize that everything the US does, basically, is about getting some gerontocratic asswipe re-elected. “Tarnished legacy”? Well, nothing tarnishes your legacy like it being revealed, later, that you misled the public. Oh, who am I kidding?

By the way, in At The Abyss [wc] Tom Reed mentions, in passing, the degree to which the science of nuclear forensics has advanced. The simple way to think about it is: it’s impossible to produce an anonymous nuke. That’s an important plot device in some of the ridiculous threat-scenarios totalitarian Americans love to worry about: a secret North Korean nuke that plunges the US into electromagnetic-pulse stone-age; it’s not going to happen because samples of the explosion’s byproduct include a detailed “fingerprint” from which nuclear forensic scientists can tell what breeder reactor bred the plutonium, in which kind, as well as the type of centrifuges that were used and how much use the cascade had gotten. The articles linked in the Foreign Policy piece don’t mention that, though it’s absolutely certain that an airplane got down there and collected samples of the explosion by-product. Then, I guess, they said, “we don’t know this reactor” and “let’s call it ‘Dimona’ and if we see this fingerprint again, we’ll know.”

Back to SpaceX:

Musk’s satellites are part of a broader Pentagon plan to pepper the sky with hundreds of satellites with multiple functions. The SpaceX satellites are meant explicitly to track and monitor threats in the sky as part of what the Pentagon calls “Tranche 0.” According to an SDA press release, Tranche 0 will have 28 transport sattleties [sic] and 8 tracking satellites.

Transport, eh? Given that the US can transport most things normally, very quickly, there’s only one thing I can imagine requires space-based ‘transport’ – perhaps some kind of anti-satellite kill vehicle, or one of the new next-generation super-precise nuclear weapons. There is a non-militarization treaty about space, but do you expect the US to be bound by something like that, when they can say the Russians are cheating?

I’m curious how the detectors work. Presumably there’s a missile launch detector and some kind of additional detection on top of that when the hypersonic engine kicks in. Is there something particularly distinctive about those? Or are they optically searching for small things moving very, very fast?

Whatever it is, it looks expensive

Welcome to the military/industrial complex, SpaceX! And fuck you thoroughly you traitors to humanity.

They will not find any alien spacecraft, but, if there were, I’d expect such a system to detect them.

Another possibility is that the “transport” is kinetic re-entry kill vehicles. What, in high school, we called “space spears” – you just drop a self-piloting piece of ceramic-coated I-beam on a target from orbit. It’s clean, it’s instant, and it’s lethal.

The SDA is a Pentagon agency tasked with weaponizing space for U.S. interests and defense.. “The SDA will define and monitor the Department’s future threat-driven space architecture and will accelerate the development and fielding of new military space capabilities necessary to ensure our technological and military advantage in space for national defense,” explained a 2019 memo creating the agency. 

Good god, George Orwell was like Nostradamus. I can’t parse that into anything but, “weaponize space like we said we wouldn’t.”

Defense versus offense: some might claim that a space-based “defense” system is only “defensive.” Well… If that’s true a castle is only “defensive” right? Anyone who claims a military system is “defensive” is either ignorant or a liar and I know which this is.


  1. says


    Transport, eh? Given that the US can transport most things normally, very quickly, there’s only one thing I can imagine requires space-based ‘transport’ – perhaps some kind of anti-satellite kill vehicle …

    In your “SDA rendering” picture, “Space Transport Layer” is in the same colour and under “Battle Management Navigation”, which makes your assumption plausible.

  2. Bruce says

    The phrases missile-tracking and missile-threats imply these are “defensive” oriented. But if any administration of any country were wishing for an attack system, missile-tracking could be useful for guiding our own “defensive” space attack missiles, in case the President wants to attack Portland or wherever from space.

  3. aquietvoice says

    Heya! Important point about the double flash – all nukes make them, not just two-stage nukes.

    The important piece of physics is that the first flash is from the X-Ray fireball, and the second flash is from the compression fireball.

    This also means that nothing – *nothing* – except a nuke can create the double flash. Nothing else produces two separate fireballs together from different sources on that timescale – which makes a double flash so distinctive (and bright!) that detecting one is an incredibly certain and authentic measurement.

    So yeah, that’s why I will never believe it was a meteor. A double flash isn’t just “a flash that is bright and happens twice”, the timescales involved and the ratio of the brightness of the flashes is incredibly distinct. That is why the bhangmeter was invented in the first place, it’s a triple fingerprint in a single measurement and relates fundamentally to the physics of the release of nuclear energy.

    We don’t have access to the design of the bhangmeter in the satellite, but even following the basic ideas about what it is supposed to do, I don’t believe a meteor – or any other phenomena – could fool one.

  4. says

    it’s a triple fingerprint in a single measurement and relates fundamentally to the physics of the release of nuclear energy.

    I believe you can also calculate the yield (and therefore infer a lot about the design) of a bomb from the timing and amplitude of the clicks.

    I thought fission-only bombs just made a single click – the xray burst, and in a fusion bomb the second click was the ignition of the secondary fusion fuel. That must be wrong, though, and I have no idea what Khariton’s “layer cake” device would produce. Needless to say, there is not a lot of published information about that stuff.

  5. Pierce R. Butler says

    The sensors were called, appropriately, “bhangmeters.”

    “Bangmeters” would make sense, but that additional “h” introduces some stony terminological distractions.

    The SDA is a Pentagon agency tasked with weaponizing space for U.S. interests and defense.

    a) Doesn’t that explicitly violate certain treaties nominally still binding on the US?

    b) Why don’t the Seventh-Day Adventists stand up and defend their acronym?

  6. lorn says

    Launch is, as I understand it, detected by the ‘thermal bloom’ and confirmed by by it gaining altitude. I used to drink with a guy who helped set up one of the monitoring systems. PhD Physics and math specialized in remote sensing. Always funny, usually brilliant, frequently drunk.

    Most of this is based upon simple pulse detection and triangulation. And the fact that the EM pulse echoes across the globe. One of the first reliable systems tracks the location of every lightning strike on earth. Accuracy varies by location but in the US it is accurate to a few meters. If you claim lightning damage to insured property they can very easily and accurately tell by checking the logs.

    I was involved in a few cases. A guy claimed damage because his neighbor got a check for a couple thousand so he figured he could just make a claim and score. They shot his claim down. And rightly so. Another time a family suffered what looked like lightning damage but there were no strikes logged. We tracked it down to a transformer failure that the POCO had neglected to report. Again, lightning trackers worked. POCO paid for a rewire. Could have burned the house down.

    Pretty amazing in my book. Anywhere. Any time. Something as small and ubiquitous, I’m in Florida so lots of thunder boomers, as lightning. Nukes? Sure. Huge flash-bang and EM pulse. Even the small ones as I understand it. No doubt they stand out if you are listening on the right frequencies.

  7. StevoR says

    Tangential but perhaps (hopefully) also of interest here :


    The United States’ space policy threatens the safe and sustainable development of the final frontier, two researchers argue.

    The U.S. is pushing national rather than multilateral regulation of space mining, an approach that could have serious negative consequences, astronomer Aaron Boley and political scientist Michael Byers, both of the University of British Columbia in Vancouver, write in a “Policy Forum” piece that was published online today (Oct. 8) in the journal Science.

    Boley and Byers cite the 2015 passage of the Commercial Space Launch Competitiveness Act, which explicitly granted American companies and citizens the right to mine and sell space resources. That right was affirmed this past April in an executive order signed by President Donald Trump, they note… (snip) .. “Meanwhile, NASA’s actions must be seen for what they are — a concerted, strategic effort to redirect international space cooperation in favor of short-term U.S. commercial interests, with little regard for the risks involved,” Boley and Byers add.

    The researchers worry that the U.S. is setting an unfortunate precedent for other countries to follow, and that space mining and other exploration activities may therefore proceed in a somewhat careless and chaotic fashion in the not-too-distant future.”

  8. dashdsrdash says

    Didn’t we already establish that space spears / rods from God were terrible at an anti-missile role but pretty good as a threat against fixed landmarks?

  9. John Morales says


    “Not because SpaceX is not qualified to do this, but because it shows that the military/industrial complex has gotten their nose under the tent.”

    “Not because SpaceX is not qualified to do this, but because it shows that SpaceX has become part of the military/industrial complex.”

    (or, that’s how I read it)

  10. aquietvoice says

    #5, Marcus Ranum:

    Aha! I think I can clear things up with another fun piece of physics:
    The X-Ray flash from a nuke doesn’t come through in X-Rays, it comes through as bright, but visible, light. Odd, no?

    See, the thing is, X-Rays get absorbed by air. I mean, not a lot, but air isn’t perfectly transparent for them.
    Plain, regular air that has not been ionized is pretty awful at absorbing X-Rays, though.

    Do you know what is good at absorbing X-Rays? Ionized air. Do you know what happens to air that absorbs X-Rays? It becomes ionized.

    At any sensible levels of radiation this means nothing. The air recombines and cools so fast that nothing happens.
    In a nuke, the volume around the core gets absolutely saturated with X-Rays, to the extent that they ionize the air and then dump all their energy into the ionized volume.

    The X-Rays manage to do this very quickly – traveling at the speed of light and all – so the first fireball appears *around* the nuke before any other energy components get anything done. This is the first flash.

    The X-Rays don’t contain the bulk of the energy, though, and so the first fireball is swallowed a short time later by another fireball that is also absorbing radiation inside it, though much more efficiently since it is carrying a lot of hot, dense matter with it. When that fireball expands and cools enough to let light out, you get the second flash.

    This is why the second flash is bigger, this is why the time difference and energy ratio are so important for understanding the design.

    This is also why it’s such a fingerprint. To get a double fireball with timing like this you really, really need something that is an incredible X-Ray source *and* an incredible thermal source at the same time. The release needs to occur over an incredibly short duration, and more than that it needs to occur with exactly the same epicenter so that the second fireball swallows and dims the first.

  11. Dunc says

    This bothers me a lot. Not because SpaceX is not qualified to do this, but because it shows that the military/industrial complex has gotten their nose under the tent.

    Lol. SpaceX is a commercial launch venture. The big money is in the hands of the military / industrial complex. It seems likely that the tent was specifically built with them in mind.

    Unless you think Elon Musk is the kind of guy to ignore his biggest and most valuable potential customer for ethical reasons…

  12. cvoinescu says

    It may have appealed to him to have bhangmeters, which are named after a variety of weed, on his satellites.

  13. says

    Actually South Africa’s nuclear program did produce bombs. They managed to produce 6 “gun type” Uranium 235 bombs, and were working on a 7th, when it was decided to stop the bomb program in 1989. All the bombs were disassambled.

  14. rrutis1 says

    Am I remembering wrong or was there an article in SciAm back in the late 80s about lighting “superbolts” causing a double flash like a nuke? I swear reading about it and thinking that it was a convenient way to hide the fact that nuclear bomb testing was still taking place from the public.

  15. says

    It may have appealed to him to have bhangmeters, which are named after a variety of weed, on his satellites.

    Could be!

    The way the name “bhangmeter” happened is probably that a Site Security Officer (SSO) red-flagged the codename for a project component. “You can’t call it ‘bangmeter’ because that’s a bit too obvious.” And some wise-snarking scientist said, “right-o, ‘bhangmeter’ it is!” Allegedly, codenames for classified projects are pulled at random from a book, but I don’t believe it for a second – I’ve seen satellite data collection programs named “SKYSWEEP” for example.

  16. says

    Thank you for that. I clearly didn’t understand it – and it didn’t make sense because then I’d expect an H-bomb to make a triple-click. And I totally understand, now, how the amplitude of the second click is going to be a great fingerprint for the yield. That also answers the question of why a “layer cake” fission/fusion-pumped bomb would still make the characteristic double click.

  17. says

    Unless you think Elon Musk is the kind of guy to ignore his biggest and most valuable potential customer for ethical reasons.

    No, not for a second am I lacking in cynicism. I’m mostly harping on it for the sake of the dwindling number of technology-optimists who think Elon Musk is going make the world a better place.

  18. aquietvoice says

    Marcus Ranum, @17:
    Huzzah! There’s a great satisfaction to being able to show someone a neat piece of physics – and then the person understands really well straight away and finds it useful. :)

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