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Somebody moved the UK's oldest satellite in the mid 1970s, but no one knows who

bbc.co.uk

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Re: Somebody moved the UK's oldest satellite in the mid 1970s, but no one knows who

#31

Post by zamadatix »

Denvercoder9 wrote: post #29
retrac wrote: post #9

There was remarkably little in the way of security for early satellites (or space probes). I recently encountered here on HN the suggestion that, the main reason you can't find particularly in-depth details on the Voyager space probes, is project security. Security through obscurity, mostly. If amateurs can detect the signal from the Voyager probes with a small dish antenna, it's at least conceivable someone might ho…

> If amateurs can detect the signal from the Voyager probes with a small dish antenna They can't, at least not for any reasonable definition of small. As I'm writing this, NASA is listening to Voyager using the DSS-14 antenna of the Deep Space Network, a dish with a 70 meter diameter, and the signal it receives is 10^-19 Watt. That's only 15000 photons per second. Coincidentally the area of that 70 meter dish is also…

If 70 m is the diameter, not radius, that area is a factor of 4 too high. Should be more like ~3850 m^2. Still physically impossible at that size but it does make the required size a bit more tenable.

Re: Somebody moved the UK's oldest satellite in the mid 1970s, but no one knows who

#32

Post by emchammer »

retrac wrote: post #9

There was remarkably little in the way of security for early satellites (or space probes). I recently encountered here on HN the suggestion that, the main reason you can't find particularly in-depth details on the Voyager space probes, is project security. Security through obscurity, mostly. If amateurs can detect the signal from the Voyager probes with a small dish antenna, it's at least conceivable someone might ho…

Documentation and logs of the Voyager and Apollo projects are public, comprehensive, and fascinating reading. They do use authentication and keep the keys secret. They are literally rocket scientists.

Re: Somebody moved the UK's oldest satellite in the mid 1970s, but no one knows who

#33

Post by dgfitz »

zamadatix wrote: post #31
Denvercoder9 wrote: post #29

Earlier quoted context omitted.

> If amateurs can detect the signal from the Voyager probes with a small dish antenna They can't, at least not for any reasonable definition of small. As I'm writing this, NASA is listening to Voyager using the DSS-14 antenna of the Deep Space Network, a dish with a 70 meter diameter, and the signal it receives is 10^-19 Watt. That's only 15000 photons per second. Coincidentally the area of that 70 meter dish is also…

If 70 m is the diameter, not radius, that area is a factor of 4 too high. Should be more like ~3850 m^2. Still physically impossible at that size but it does make the required size a bit more tenable.

For those using freedom units that is about 200ft diameter, or about 31,000 square feet.

This works out to roughly 0.7 acres.

Re: Somebody moved the UK's oldest satellite in the mid 1970s, but no one knows who

#34

Post by dgfitz »

emchammer wrote: post #32
retrac wrote: post #9

There was remarkably little in the way of security for early satellites (or space probes). I recently encountered here on HN the suggestion that, the main reason you can't find particularly in-depth details on the Voyager space probes, is project security. Security through obscurity, mostly. If amateurs can detect the signal from the Voyager probes with a small dish antenna, it's at least conceivable someone might ho…

Documentation and logs of the Voyager and Apollo projects are public, comprehensive, and fascinating reading. They do use authentication and keep the keys secret. They are literally rocket scientists.

I think it’s even more amusing that that, these folks invented rocket science.

Re: Somebody moved the UK's oldest satellite in the mid 1970s, but no one knows who

#35

Post by justsomehnguy »

zamadatix wrote: post #31
Denvercoder9 wrote: post #29

Earlier quoted context omitted.

> If amateurs can detect the signal from the Voyager probes with a small dish antenna They can't, at least not for any reasonable definition of small. As I'm writing this, NASA is listening to Voyager using the DSS-14 antenna of the Deep Space Network, a dish with a 70 meter diameter, and the signal it receives is 10^-19 Watt. That's only 15000 photons per second. Coincidentally the area of that 70 meter dish is also…

If 70 m is the diameter, not radius, that area is a factor of 4 too high. Should be more like ~3850 m^2. Still physically impossible at that size but it does make the required size a bit more tenable.

        Antennas at Goldstone Deep Space Communications Complex 
        Name                       Diameter  Description
        DSS 12: "Echo"             34m       Decommissioned in 2012.
        DSS 13: "Venus"            34m       Beam waveguide antenna (BWG) on altazimuth mount, located in Venus, California. ~910 m2 aperture.
    ->  DSS 14: "Mars"             70m       Cassegrain reflector on Alt/Az mount. ~3850 m2 aperture.
        DSS 15: "Uranus"           34m       "High Efficiency" reflector on Alt/Az mount
        DSS 24, 25, 26: "Apollo"   34 m      BWG reflector on Alt/Az mount
        DSS 27, 28: "Gemini"       34 m      BWG reflector on "High Speed" Alt/Az mount
https://en.wikipedia.org/wiki/Goldstone_Deep_Space_Communica...

Re: Somebody moved the UK's oldest satellite in the mid 1970s, but no one knows who

#36

Post by sandworm101 »

Denvercoder9 wrote: post #29
retrac wrote: post #9

There was remarkably little in the way of security for early satellites (or space probes). I recently encountered here on HN the suggestion that, the main reason you can't find particularly in-depth details on the Voyager space probes, is project security. Security through obscurity, mostly. If amateurs can detect the signal from the Voyager probes with a small dish antenna, it's at least conceivable someone might ho…

> If amateurs can detect the signal from the Voyager probes with a small dish antenna They can't, at least not for any reasonable definition of small. As I'm writing this, NASA is listening to Voyager using the DSS-14 antenna of the Deep Space Network, a dish with a 70 meter diameter, and the signal it receives is 10^-19 Watt. That's only 15000 photons per second. Coincidentally the area of that 70 meter dish is also…

But you dont need to hear voyager in order to hack it. It just needs to hear you. Nasa needs the big dish to hear voyager's tiny transmitters. Someone wanting to send a disruptive message to voyager could use a massive transmitter and a relatively smaller dish.

But you dont even need that. You need just enough outbound signal to jam the legitimate uplink, enough that voyager can no longer tell you from the real signal. That is likely much less than the power needed to send a command.

Or you could jam the nasa ground stations. A one-watt transmitter on a carefully positioned cubesat in low orbit would be enough to nullify voyager's real signal. (Setup the orbit to be over the deep space network stations every day as voyager comes into view.)

Re: Somebody moved the UK's oldest satellite in the mid 1970s, but no one knows who

#37

Post by gloflo »

emchammer wrote: post #32
retrac wrote: post #9

There was remarkably little in the way of security for early satellites (or space probes). I recently encountered here on HN the suggestion that, the main reason you can't find particularly in-depth details on the Voyager space probes, is project security. Security through obscurity, mostly. If amateurs can detect the signal from the Voyager probes with a small dish antenna, it's at least conceivable someone might ho…

Documentation and logs of the Voyager and Apollo projects are public, comprehensive, and fascinating reading. They do use authentication and keep the keys secret. They are literally rocket scientists.

Was there authentication right from the beginning or was it patched in later?

Re: Somebody moved the UK's oldest satellite in the mid 1970s, but no one knows who

#38

Post by sandworm101 »

ben_w wrote: post #21
PittleyDunkin wrote: post #15

Earlier quoted context omitted.

> There was remarkably little in the way of security for early satellites (or space probes). Compared to what? What was (or is) worth securing? From what? Talking about security in abstract is nonsensical

The early stuff was spy satellites, weather satellites, and communication satellites. The earliest active communication satellites — e.g. Telstar 1 — was done with "take signal in from vaguely the right direction, amplify with pure circuitry, rebroadcast in vaguely the right direction", no encryption possible on the satellite itself, and the thing itself was so primitive it was spin-stabilised rather than having an a…

These were and are called "bent pipe" satalites as they deftly turn around an amplified signal. But their control circuits are different and are not so open.

For the airplane nerds, this was also how early radar jammers worked. They took an incomming radar signal, delayed it a little, and retransmitted. No processing required and no digital circuits. That worked very well once upon a time.

Re: Somebody moved the UK's oldest satellite in the mid 1970s, but no one knows who

#39

Post by manquer »

sandworm101 wrote: post #36
Denvercoder9 wrote: post #29

Earlier quoted context omitted.

> If amateurs can detect the signal from the Voyager probes with a small dish antenna They can't, at least not for any reasonable definition of small. As I'm writing this, NASA is listening to Voyager using the DSS-14 antenna of the Deep Space Network, a dish with a 70 meter diameter, and the signal it receives is 10^-19 Watt. That's only 15000 photons per second. Coincidentally the area of that 70 meter dish is also…

But you dont need to hear voyager in order to hack it. It just needs to hear you . Nasa needs the big dish to hear voyager's tiny transmitters. Someone wanting to send a disruptive message to voyager could use a massive transmitter and a relatively smaller dish. But you dont even need that. You need just enough outbound signal to jam the legitimate uplink, enough that voyager can no longer tell you from the real sign…

Even then you need a fairly large transmitter. It is quite easy to detect EM transmissions even when they are low energy. This would be incredibly easy to detect. There are plenty of regulations already by FCC, ITU and equivalent on what is allowed on what wavelength which most nations are signatories too.

Violating these is already solved by law enforcement, even if a rogue nation state is protecting you it will be handled with big gun diplomacy, America after all has the biggest guns.

As xkcd put it, $5 wrench is all it takes no matter how strong your encryption, that works both ways, if a government can find a malicious actor all it takes is $5 wrench to stop you. There is limited value for nation state to protect you from hacking voyager, there is no military or strategic value in it. Dormant satellites in LEO or GEO can be used as kinetic weapons so are lot more valuable.

There are also tech solutions like active jamming that could easily be deployed to counteract you that civilized world can use first even if they don't/can't blow you up without risking retaliation from your state sponsor.

Re: Somebody moved the UK's oldest satellite in the mid 1970s, but no one knows who

#40

Post by vdvsvwvwvwvwv »

dgfitz wrote: post #33
zamadatix wrote: post #31

Earlier quoted context omitted.

If 70 m is the diameter, not radius, that area is a factor of 4 too high. Should be more like ~3850 m^2. Still physically impossible at that size but it does make the required size a bit more tenable.

For those using freedom units that is about 200ft diameter, or about 31,000 square feet. This works out to roughly 0.7 acres.

Funny enough the foot was restandardized to .3048m in 1959. So it is a metric-derived unit. Before that it was a feifdom unit, set by kings.
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