Thread

NASA asked several former SR-71A staffers to help secret restart

327 points · 403 comments · ilamont

walrus01 · 1790727565 · focus · HN ↗
I'd be more astonished if there isn't something superior to the SR71 (likely unmanned) that has been flying around at night from facilities like Groom Lake for years. Look at how long the RQ180 was flying around in semi-public and known about before it became seen in daylight by plane spotters in Greece. And a long time before that there were public relations approved photos of the Lockheed Martin Polecat.
There were a series of extremely public quotations from senior DoD officially recently about how they plan to aggressively retire the Global Hawk program (which is a mostly non stealth aircraft), reading between the lines it's because they have something much better.
edit: for those who haven't seen the RQ180: <a href="https://www.google.com/search?client=firefox-b-d&q=RQ180+greece" rel="nofollow">https://www.google.com/search?client=firefox-b-d&q=RQ180+gre...
edit 2 (apologies for the X link): <a href="https://x.com/MechDesignxyz/status/2041281689838584193" rel="nofollow">https://x.com/MechDesignxyz/status/2041281689838584193
1. hilsdev · 1790727775 · focus · HN ↗
  I suspect everything comparable of late has been orbital, which begs the question what is it they’re worried about with orbital? Satellite warfare is already accelerating if the rumors are true, is it that this is untouchable still? Is there some new camera sensor where eliminating that extra atmospheric diffraction or slowing down (lol) is needed?
  1. walrus01 · 1790727944 · focus · HN ↗
    I am sure that the orbital capabilities are also vastly improved from what the public has ever seen. But I think there's likely a high degree of tactical value in having something that can keep station over a certain active conflict area (as an RQ180 can, maybe flying in a racetrack pattern at altitude, with sensors aimed down).
    If you've ever seen the publicly released videos and audio of an RQ9 operator in communication with ground units watching the activity of a group of men/vehicles on the ground, in live real time, something like that.
    As compared to periodic revisits by LEO orbit satellites that don't maintain persistent live coverage, or the extreme distance and data acquisition problem that aiming sensors in geostationary orbit at a 10x10km target area might pose.
    Demiurge · 1790730404 · focus · HN ↗
    There are satellites in geostationary orbit that have realtime live feed and agile pointing capability. However, besides the SAR, RGB style observations are limited by clouds, and also you can’t switch out the sensors on a whim. Airborne platforms are always more flexible and cheaper for certain missions.
    adastra22 · 1790731526 · focus · HN ↗
    I think you are confused. Spy satellites do not use geostationary orbits.
    walrus01 · 1790731837 · focus · HN ↗
    It's not something I can cite with any public URL to a website that's an authoritative source, but if by 'spy' you include SIGINT satellites in that category, yes they absolutely do... Ever seen a diagram of a Boeing (Hughes) 702 series satellite bus and antenna system built for L/S-bands like frequency ranges similar to those used by Thuraya, Inmarsat and Iridium handhelds?
    It's widely accepted in the commercial two way satellite telecom industry that the NSA has comparable things with big unfolding umbrella-like antennas in geostationary which serve a similar purpose for signals collection.
    ErroneousBosh · 1790753741 · focus · HN ↗
    > It's widely accepted in the commercial two way satellite telecom industry that the NSA has comparable things with big unfolding umbrella-like antennas in geostationary which serve a similar purpose for signals collection.
    How does that even work, do people just accept that their satellites hang around suspiciously close to other geostationary satellites and hoover up the very edge of the beam somehow?
    Because if you're transmitting stuff *to* geosynchronous birds you have to aim pretty accurately.
    walrus01 · 1790754980 · focus · HN ↗
    Handheld S/L-band things like Thuraya, Iridium, Globalstar, Inmarsat phones don't transmit in a very directional way at all. Or things like a Garmin inreach that have an Iridium modem in them. They're omnidirectional enough that the broad requirement for a user is to be outdoors with a good view of the sky.
    If you have a NSA-type geostationary satellite somewhere in approximately a 1/5th arc of azimuth along the equator of the earth that can 'see' an area on the ground, with antenna systems aimed at the area of interest (let's say, Afghanistan), it's not necessary for your NSA satellite to be anywhere close to the actual service provider's satellite.
    Note that Thuraya BGAN-like devices and handheld phones talk to geostationary, Iridium is LEO (but likely some combination of LEO, molniya orbit and geostationary can "sniff" it), Globalstar is similarly LEO in its service provider architecture, and Inmarsat is geostationary.
    Also lots of conjecture out there that sigint platforms exist which are good enough to capture ordinary handheld device cellular traffic or VHF/UHF radio traffic that's not intended by its users or terrestrial operators to go into space at all. This is probably done from a combination of low earth orbit platforms and more complicated orbits or what we would call MEO (maybe about the same height as an o3b satellite?) to achieve longer dwell times over an area of interest.
    ErroneousBosh · 1790756677 · focus · HN ↗
    But then with the difference in distance from LEO stuff like Iridium (RIP - I actually saw the ground flash of an Iridium flare once!) you'd need a truly *massive* antenna to hear that out at geosync.
    walrus01 · 1790761766 · focus · HN ↗
    An Iridium 9555 handheld phone talking to Iridium satellites in LEO with its antenna extended transmits in approximately the same frequency range and about the same tx power as an inmarsat isatphone 2. The former is LEO, the latter talks to geostationary.
    Same concept for an Iridium 9555 or its successor in a dock plugged into the small coaxial cable that goes to the external hockey puck sized antenna. This is all happening between approx. 1400 to 1700 MHz in either system.
    Look up the detailed RF specs for the isatphone 2.
    Both of these only work because the channel size is extremely narrow.
    The antenna on the commercial satellites that do two way S/L-band to handheld stuff (or INMARSAT BGAN size terminals) from geostationary is massive, I've no reason to believe that a high budget billion dollar NSA satellite at MEO or higher altitudes wouldn't have a similarly gargantuan unfolding antenna.
    T-A · 1790763327 · focus · HN ↗
    <a href="https://en.wikipedia.org/wiki/Orion_(satellite)" rel="nofollow">https://en.wikipedia.org/wiki/Orion_(satellite)
    adastra22 · 1790809092 · focus · HN ↗
    The NSA does have comparable things. You can even find amateur photos of them in this day and age. But they are not in GEO.
    LorenPechtel · 1790813889 · focus · HN ↗
    The ground units do not have any sort of narrow beam capability, thus you don't need to be anywhere near the satellite to intercept them. I have a low end satellite device: Garmin InReach (text only, provides tracking and emergency communications in the middle of nowhere.) It has a preferred orientation, not a required orientation.
    Demiurge · 1790734916 · focus · HN ↗
    Why do you think I am confused? Is this a form of internet condenscension, or are you able to diagnose my mental state based a single comment? No, I don't think I'm confused.
    adastra22 · 1790809341 · focus · HN ↗
    Because GEO is about 100x further than LEO, which means the signal is about 10,000x weaker. Also the risk to geo communications from having multiple birds in the same slot is huge and treaty violating. Why put that risk and insane demand when you can still get global coverage from a dozen or so birds in high polar orbits?
    Nobody does what you are saying, because physics, which leads me to believe that you are confused.
    walrus01 · 1790812844 · focus · HN ↗
    If you think the US doesn't have a plethora of DoD things in geostationary orbit you would be extremely, terribly wrong. In addition to well known programs like AEHF, WGS for two way military satcom purposes, a person with an amateur grade telescope can literally spot the satellite that keeps station near an existing commercial Thuraya satellite:
    <a href="https://en.wikipedia.org/wiki/USA-202" rel="nofollow">https://en.wikipedia.org/wiki/USA-202
    <a href="https://space.skyrocket.de/doc_sdat/thuraya-2.htm" rel="nofollow">https://space.skyrocket.de/doc_sdat/thuraya-2.htm
    <a href="https://space.skyrocket.de/doc_sdat/thuraya-4.htm" rel="nofollow">https://space.skyrocket.de/doc_sdat/thuraya-4.htm
    adastra22 · 1790826000 · focus · HN ↗
    Those are geosat communications, not surveillance. Surveillance is not happening in GEO.

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