10 ms·
A New Satellite Can Peer Inside Buildings, Day or Night
- lemonspat 6y agoThe DoD (or the NRO) had this tech in the 80s? Wasn’t this SAR originally in the form of ground penetrating radar invention for finding nukes in ground siloes?
- geomark 6y agoAlso used to track submerged submarines by detecting ocean surface disturbances caused by the underwater wake of the submarine. Same benefits: works at night and through cloud cover.
- lemonspat 6y agoThat is astounding! something I was unaware about before. At what depth could it be measured?
- grendelt 6y agoAlmost any depth. A big steel tube is going to displace water. Once you have some baseline measurements (of known underwater landforms), then small imperceptible variations would stick out.
- SirLuxuryYacht 6y agoNot possible. The uncertainty of bathymetry in areas only mapped using gravity is larger than the dimensions of a sub. Even in very well mapped areas, think of the effort in the Indian ocean to find MH370, this would require the assumption that the sub is moving, which is not always the case, e.g. if the sub halts propulsion and drifts with a current.
- geomark 6y agoWell yes, it's the surface disturbance of the underwater wake that they are detecting. So the sub has to be moving under its own power. But there is no need for high resolution and the wake of the sub stands out starkly even with a large field of view. So I'm not sure it can evade detection by halting propulsion and drifting. The point at which it halted would be known and it would be detected as soon as it restarted, unless it was carried by an unknown current far enough to be out of view of the satellite.
- baybal2 6y agoThe infamed laser on Tu 142 was said to get to only get to 50m, but that was a "direct imager" which relied on direct reflection, and seventies-eighties era technology. Newer ones are directly sensing density, and temperature changes in the seawater by sensing Raman shift, and are supposedly much better. No known data in public of course.
- aerostable_slug 6y agoTracking submerged boats from space is the holy grail of ASW, and as best as I can tell it doesn't work outside littoral zones (where sometimes you can optically detect the sub) and contrived tests. It has been tried with SAR, blue/green lasers, IR, all kinds of stuff, and luckily it doesn't work in the real world. When it does, it will be massively destabilizing as it places the "invulnerable" second strike capability that guarantees deterrence against peer states at risk.
- baybal2 6y ago> When it does, it will be massively destabilizing as it places the "invulnerable" second strike capability that guarantees deterrence against peer states at risk. It never been such to begin width, at least by the late cold war, some portion of missile subs were reliably tailed by adversaries without any high tech trickery. North Korea, Russia, and China each already have more submarines than USA, and would have no problem to put 10 subs to tail each Ohio.
- unchocked 6y agoTailing some portion of missile subs won't do - a single missile sub is an existential threat so deterrence isn't destabilized until the adversary can credibly eliminate all of them within ~10 minutes. It takes a nuclear sub to trail a nuclear sub. NK and China have exclusively, and primarily (respectively) diesel subs. These have to surface and run their engines to charge batteries. They cannot make 20+ knots submerged for long, and they cannot track deeply submerged submarines from the surface. Surfacing and running diesels would make their presence known. They cannot range far from port, and certainly cannot track missile boats under the arctic ice. Russia has a sufficiently large nuclear fleet, but it is outdated and probably outclassed by US technology. There is probably greater disparity between the powers than existed during the cold war, at which time deterrence was credible.
- tomatotomato37 6y agoHere's all the specs I could find for the satellite itself. https://space.skyrocket.de/doc_sdat/capella-2.htm https://space.skyrocket.de/doc_sdat/capella-2.htm
- heyflyguy 6y agoThis is cool tech and there are new players entering this field with even better capability. The Clinton era laws of optical resolution restrictions seems silly now with this tech in the commercial marketplace.
- mvanaltvorst 6y agoI'm curious, which new competitors do you mean precisely? Do they have better capabilities than Capella? This seems like a great upcoming industry
- raws 6y agoLaw in the USA limits to 50cm, there's one out there that's 25cm (link in a comment above).
- hungryforcodes 6y agoI'm not really sure what is so cool about this. It seems incredibly invasive.
- geomark 6y agoArticle says they are by law limited to 50cm resolution. But there was another SAR satellite launched in March 2020 that claims 25cm resolution.[1] [1] https://apnews.com/press-release/pr-prnewswire/d35f7cb315af01e30723b924c4137152 https://apnews.com/press-release/pr-prnewswire/d35f7cb315af0...
- a3n 6y agoYour linked article says that satellite's company is Finnish, not US.
- raws 6y agoI think he's just alluding to the fact that there's already better ones out there for other countries, maybe even better for secret military bodies.
- garettmd 6y agoAnd just because they have that capability, doesn't mean they can "legally" use it. The posted article says that it can do a better resolution than that 50cm, but didn't specify how much better.
- geomark 6y agoICEYE's website says high res (25cm) imaging is commercially available. Even has some sample 25cm res images available for download at the bottom of this page (I have not downloaded so can't vouch for it) https://www.iceye.com/satellite-data/blog/new-benchmark-in-imaging-from-sar-microsatellites-iceye-presents-25-cm-azimuth-resolution https://www.iceye.com/satellite-data/blog/new-benchmark-in-i...
- geomark 6y agoThat's right. The article says "...other SAR satellites on the market can only get down to around five meters" which isn't true if the story I linked is accurate.
- OneGuy123 6y ago> Banazadeh said that the original image was so detailed you could check out individual rooms. "Hello this is the EU, you satellite does not comply with GDPR".
- yummypaint 6y agoI wonder how intense those microwaves are in a room being scanned. Presumably it's also possible to jam these scans, but it seems that doing so would invoke the wrath of the fcc.
- rathel 6y agoCorner reflectors are crazy effective for such application, as referenced in another comment thread here.
- motohagiography 6y agoIn the 9ghz range, does that mean a sub-1mm wire mesh could mitigate this? Asking for a hypothetical house renovator friend. Thompson's adage of when the going gets weird, the weird turn pro suggests that the tinfoil hat crowd could be able to corner the emerging domestic Faraday cage market.
- leoedin 6y agoIf you want to block SAR, just set up a big corner reflector near you. It'll completely blind the part of the image near you. It would also draw a lot of attention to you... So maybe not the best approach if you're trying to hide.
- craftinator 6y agoWell, if enough people do it... Let's make a VPN for satellite surveillance
- jusssi 6y agoBig in home decoration fashion next year, upside down pyramids hanging from the ceiling. (edit: my bad, a corner reflector would have 3 corners at the base, not 4 as a pyramid would)
- AlgorithmicTime 6y agoA pyramid is defined as any polygonal base with all vertices connected to an apex, so a triangular pyramid is possible.
- artvark11 6y agoHow big are we talking? Can I make one out of tinfoil?
- ars 6y agoAre you sure a corner reflector will work? The entire premise of the synthetic aperture is that the transmission and reception are distant from each other, but a corner reflector will reflect back to the location of the transmission - i.e. it will entirely miss the receiver.
- bsenftner 6y agoSounds like an set of interesting problems for computer vision careers.
- choeger 6y agoCombine this technology with the launch cadence and pricing of SpaceX and the implications are astounding. First of all, security. If your opponent has that kind of capability, you cannot meaningfully deploy tanks or any other vehicles anymore. Even infantry will suffer massively once the resolution goes up a notch. On a much smaller level, one could easily detect brake-in attempts on unguarded property. Second, industrial espionage. Want to know how much the competition buys/sells? Plug this data into some form of image recognition. Third, government control. From traffic over demonstrations to "unsocial" behavior, governments at the municipal level could easily inspect "their" people and control their behavior much more efficiently.
- shubb 6y agoWorth noting that we don't know what most spy satellites are, but the US has revealed that it has had a constellation of 5 satellites like this since about 2000. So this is bringing the technology into the civilian sphere with an API 'only'. But yeah, I agree with you about the potential. Also, presumably a constellation imaging the same location from multiple angles could synthesize a super high resolution 3D image?
- asdfasgasdgasdg 6y agoI thought tanks and infantry were already basically done against equiv-tech opponents. They are not sufficiently mobile to dodge the various smart weaponry we have available today.
- choeger 6y agoJust look at the Syrian civil war or the Russian invasion of the Ukraine. In both cases, Russia deployed (various quantities of) conventional forces and overwhelmed their (more or less) equally equipped opponents with tanks, vehicles, and infantry by employing better organization, tactical and strategical mobility and, to some degree, air superiority. In both cases, live satellite images at the tactical level would have made such an offensive practically impossible.
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- px43 6y agoI'd bet someone could pretty easily build an alarm that goes off every time one of these things is looking at you. That radar blast has got to be massive. This definitely couldn't be a 24/7 thing from those satellites. I wonder how much radar time one of those things has before it needs to recharge/refuel.
- leoedin 6y agoPower usage isn't necessarily huge. I worked on a SAR satellite a few years ago with a total RF power of <1kW. It's pulsed as well - you send an RF "chirp" at a sub-1kHz pulse frequency. Depending on imaging mode the average power draw is probably in the 500W-1kW range. That had a much larger resolution (6m rather than 50cm), but the resolution is a function of frequency and antenna design as much as power. The SAR concept essentially creates an image by sending out a known RF chirp and then, for each pixel of the image, correlating the response with the expected signal from that pixel. That correlation means that even if the received signal is below the noise floor you can create an image.
- px43 6y agoGreat info, much appreciated. Still seems like kind of a lot of something that's supposed to live in space for years at a time. Presumably solar panels recharge a battery when it can, but continuous operations seem out of the question without some pretty large panels. Maybe I'm underestimating modern solar panels or something.
- madlag 6y agoEfficiency of solar panels on satellites is about 40%. That means ~ 700W/m2 if correctly oriented. That's quite a lot of power, even if you stay 50% of the time in night while orbiting Earth. So no need for huge panels usually. (Updated : more like 40%, not 50%)
- asdfadsfgfdda 6y agoOr just track the orbits, these are all published by NOARD. Most satellites do not change orbits often. Even easier, Capella-1 is in a sun synchronous orbit, so it will always pass overhead at the same local time, at noon or midnight. https://www.n2yo.com/satellite/?s=43791 https://www.n2yo.com/satellite/?s=43791
- joshxyz 6y agoWhat kind of black magic fuckery is this O.o
- LeifCarrotson 6y agoSynthetic aperture radar. As an EE, I consider it important to understand that nothing at any level in your technology stack from silicon to SAAS to smartphones is black magic. This is just an application of the physics of high frequency electromagnetic signals. I haven't personally done work with SAR, but I imagine it's much the same as dealing with EMI/EMC in PCB development: extend Maxwell's equations from a simple case to the general principle, simulate, test, and tune. I'd have to go back to my textbook and review to figure out the exact mechanisms and the limiting factors for resolution and power, I think I have Johnson's "High Speed Digital Design: A Handbook of Black Magic" on a shelf around here somewhere...
- kumarvvr 6y agoThe article itself says "some" buildings. Can anyone tell me if 9.65 GHz waves can penetrate concrete / wood homes? If commercial satellites have reached this capability, military ones are definitely far ahead.
- grendelt 6y agoLikely wood, concrete would probably attenuate a fair amount but still penetrate. Modern glass-walled office buildings with metallic coating for UV and thermal insulation would probably reflect or attenuate the signal enough to be unusable. Walls with metal lattice in them (plaster, stucco) might also be difficult to penetrate.
- inakarmacoma 6y agoCan you build one of these in a non-satellite form? Like, looking inside my computer or similar, or my closed closet?
- roywiggins 6y agoYes, and law enforcement buys these things. They can see through walls. https://www.dhs.gov/sites/default/files/publications/Radar-TWS-MSR_0913-508.pdf https://www.dhs.gov/sites/default/files/publications/Radar-T...
- baybal2 6y agoThose things operate completely unlike a SAR imaging satellite.
- drtillberg 6y agoThe mystery head trauma suffered by U.S. diplomats comes to mind when discussing active-scanning satellite technology. The commerical product seems not so above-board based on the use cases discussed.
- arkh 6y ago> Another innovation, he says, is the resolution at which Capella’s satellites can collect imagery. Each pixel in one of the satellite’s images represents a 50-centimeter-by-50-centimeter square, while other SAR satellites on the market can only get down to around five meters. When it comes to actually discerning what you’re looking at from space, that makes a huge difference. If that's what is available to civilians, I'd like to see what 2020 spy satellites can do.
- capekwasright 6y agoThis is likely the best recent example (from last year): https://www.thedrive.com/the-war-zone/29634/trump-tweets-intelligence-image-after-irans-rocket-explosion-and-offers-them-best-wishes https://www.thedrive.com/the-war-zone/29634/trump-tweets-int...
- SoapSeller 6y agoIt doesn't looks like SAR to me(there are shadows, for example). More like standard optical image(the resolution and details are amazing, if it's a satellite, which is doubtful given the angle).
- sq_ 6y agoIIRC, the conclusion at the time was that that particular image was taken by an NRO KH-11 satellite - roughly equivalent to a Hubble Space Telescope pointed at earth and definitely not SAR.
- Someone1234 6y agoSupposedly this was taken by a KH-11 Block 4 (USA-224) which means this is cutting edge as of 2005. We're currently on Block 5 as of 2018. The biggest secrets within US Reconnaissance Satellites isn't really optical clarity anymore, it is their capabilities in other spectrums (and have supported at least infrared for 30+ years, but with signals intelligence well beyond that since).
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- walrus01 6y agoIf Capella is doing this and publishing images, imagine what the NRO is doing with multi-billion-dollar budgets and SAR satellites that weigh 6000 kg.
- abeppu 6y ago> The satellite beams down a powerful 9.65 GHz radio signal toward its target, and then collects and interprets the signal as it bounces back up into orbit. Years ago there were lots of articles about X-ray backscatter vans, owned by NYPD but probably also other jurisdictions. One of the concerns was you'd never know when they were scanning you and looking inside your car. But of course, though these active systems are invisible to human eyes, they do have to send out pretty strong signals. So I wonder if a kind of sousveillance is possible. Can we have devices that detect the signal being directed at the target, and alarm and publish that info? Both individuals could know if/when they are being imaged, and the public could see some patterns in who they look at. Anyone aware of how hard a detector would be to build?
- vorpalhex 6y ago9.65GHz would be outside the range of most common SDRs, but other than that it would be like detecting any other radio transmission. You would need a sample to know it's the satellite in question and not some other noise on that band, and it would be vulnerable to false positives unless the sample is unique.
- segfaultbuserr 6y agoAll an SDR needs is a frontend LNA and a downconverting mixer (collectively called a LNB). Once the frequency is brought down, all standard SDRs can be used.
- walrus01 6y agoYou could do this with spectrum analyzers intended for the commercial telecom industry, and a horn antenna with waveguide tuned to the right bands. It's not far off from the frequencies used in the standard FCC Part 101 licensed, 11 GHz FDD band plan for point to point high capacity microwave links. One of the problems would be that detecting such a thing in an omnidirectional way would be problematic and difficult, the horn antenna described above would have the vast majority of its gain when aimed in one particular azimuth and elevation.
- s5300 6y agoIs anybody else scared as absolute all fuck about this complete dystopia we're going full speed into with not even the slightest of brakes? At what point are we going to be able to distinguish those who are being always watched from the paranoid schizophrenic? LOVEINT tells us it's really just a matter of time until we hear of some worker who goes postal after tracking his love interest in everything building they go in.
- infoseek12 6y agoI’ve often wondered why no commercial satellite provider provides any kind of RF platform. I believe you could tell which power plants and factories are active and at what level from the amount of RF emissions. It seems like you could get lots of valuable information without even decoding any of the signals. Does anyone know why this service has never been offered?
- parsimo2010 6y agoWhat you’re asking about is essentially why hasn’t anyone started a civilian SIGINT/MASINT company. The main reason is cost and governments. Most civilian devices are compliant to some country’s emission standard, and don’t have a lot of spurious emissions outside of their fundamental frequency, and only use the power necessary to complete their function. Detecting these things from space is crazy hard. When your field of view is wide, you have a ton of similar signals stepping on each other. When your field of view is narrow it takes a lot of time to look at everything. Overcoming these basic problems is why the major powers of the world have to spend billions of dollars to do it. And even if you managed to fund and develop a civilian capability, you have to get permission from a major world power to launch and operate. They don’t like competition- this is why civilian space imagery has limited resolution and why Capella has to limit their resolution. Civilian SIGINT would have to be limited to the point where it has no commercial use. If civilian SIGINT were able to measure activity at factories it could measure activity at military bases and track military movements. While it would be cool to have the capability, it won’t happen soon. Not because there aren’t people smart enough to solve the technical problems, but because nobody has navigated the political issues. The people with the resources to do so are happy enough with the money they are receiving from the governments of the world.
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- mrtnmcc 6y ago>> Satellite can peer inside buildings Looking at the examples of 'ghostly buildings', it seems these are just combining different perspectives as the satellite moves. It isn't actually seeing inside the building, just 3D rendered to look transparent. 10Ghz has (optimistically) a building penetration loss of 25dB [1], with any reflections back also seeing 25dB loss. I don't think this is workable with current satellite power flux density regulations. At least not at 10Ghz. [1] ITU-R P.2346-1 https://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-P.2346-1-2016-PDF-E.pdf https://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-P.2346-1-201... Edit: the claims to seeing 'individual rooms' are not backed by any examples, but maybe natural corner reflectors could rarely give a return. Still wouldn't be able to see anything within the room.
- karmakaze 6y ago> “There’s a bunch of gaps in how we’re currently observing Earth from space [...]” It's weird to hear places that were expected to be private to be called 'gaps' like they should be visible but weren't until we had the technology to fix that. > Capella launched a platform allowing governmental or private customers to request images of anything in the world 'or private customers' adds to the looming creepiness of our future.
- rademacher 6y agoSAR has been around since the 70s and works using the same principles as CT scans (projection slice theorem). Think about observing an image by rotating it and projecting it orthogonally to the rotated direction. Take a bunch of these measurements (basically a radon transform) and then you can invert the process using the back projection algorithm. The resolution of the image is proportional to the bandwidth of the waveform and the distance traversed by the satellite during the collection process. This article is a bit of an exaggeration and Capella is certainly not the first or only SAR service.
- unchocked 6y agoNote that these 50cm image resolutions are limited by law, not technology. The US military of course has superior technology, and its resolution is unlikely to be limited by statute. The NRO Topaz satellites are the successful radar development of the two prong Future Imaging Architecture (the optical component failed, which was to be the successor to Keyhole [of which the Hubble Space Telescope is derived]) should be assumed to have capabilities far beyond those of this company. https://en.wikipedia.org/wiki/Future_Imagery_Architecture https://en.wikipedia.org/wiki/Future_Imagery_Architecture https://www.space.com/23871-air-force-spy-satellite-launch-nrol39.html https://www.space.com/23871-air-force-spy-satellite-launch-n... https://www.nytimes.com/2007/11/11/washington/11satellite.html https://www.nytimes.com/2007/11/11/washington/11satellite.ht... ^ A very well put together long read from the Times on black world contracting chaos, exemplified by these satellites.
- baybal2 6y ago> Note that these 50cm image resolutions are limited by law, not technology. By physics, and computing power. For any stable circular orbit, a satellite can only fly that fast, and the radio window would only pass so much of radio spectrum.
- Drdrdrq 6y agoExcept that they are only recording and transmitting data for a limited number of areas. Still a challenge though, I agree.
- unchocked 6y agoFrom the article, the 50cm resolution is by law. Physical limits also exist, and one presumes that military hardware is operating closer to them.
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- marsokod 6y agoCapella's competitor Iceye has already achieved 25cm. Physics limitations are even lower than that. But you are right talking about computing power. SAR work in a very different way from optical imagery and data generation/processing is quite a huge difficulty.