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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

#71

Post by iphoneisbetter »

tivert wrote: post #60
manquer wrote: post #39

Earlier quoted context omitted.

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…

> 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. No one is going to war over ITU regulations or Voyager.

[dead]

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

#72

Post by Keysh »

rhplus wrote: post #23
adrian_b wrote: post #3

TLDR: While the title says that it is not known who has moved an abandoned UK satellite used for military telecommunications, the article very strongly implies that it was someone from USA, who does not want to acknowledge this. The satellite had been built by USA and initially operated also by USA, before being handed down to the UK, so they had the capabilities to control it at any time.

Its current position above Central America would certainly have been useful to the US in the mid 1970s when it apparently moved, perhaps more useful than it would have been to the UK over post-colonial East Africa.

The article says that it was no longer functional (in its communications abilities, at least) by that point

> Launched in 1969 ... the spacecraft ceased working a few years later ...

Also, what makes you think the US didn't already have their own satellites for that purpose?

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

#73

Post by cenamus »

Yeul wrote: post #6
adrian_b wrote: post #3

TLDR: While the title says that it is not known who has moved an abandoned UK satellite used for military telecommunications, the article very strongly implies that it was someone from USA, who does not want to acknowledge this. The satellite had been built by USA and initially operated also by USA, before being handed down to the UK, so they had the capabilities to control it at any time.

UKs nuclear deterrence is built by the USA. It is a testament to deGaulle's genius that he never fell into that trap.

To be honest, most central Europeans would not have been too happy with France's early nuclear strategy. Basically just shooting a-bombs into a corridor along the Rhine to stop the Soviets

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

#75

Post by BiteCode_dev »

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.

Usually this joke flies but apparently, after the last election, people seem to take it seriously.

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

#76

Post by dtgriscom »

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…

A satellite could jam the signal for a minute or two every ninety minutes, which isn't a lot, although it might be enough to be annoying.

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

#77

Post by sandworm101 »

dtgriscom wrote: post #76
sandworm101 wrote: post #36

Earlier quoted context omitted.

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…

A satellite could jam the signal for a minute or two every ninety minutes, which isn't a lot, although it might be enough to be annoying.

Not if put into an eccentric orbit designed to have it hover in place. A tundra orbit could keep it in the way for many hours each day. Three sats could probably manage 24/7 coverage.

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

#78

Post by tzs »

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…

> […] a small dish of 1 m^2 will catch roughly 1 photon per second. Given that the datarate is 40 bits/second, it's physically plain impossible to receive the signal with a small dish.

Do you just mean plain impossible with the specific type of system used with Voyager, or are making a general argument that all systems that have a 1 photon/second rate cannot carry 40 bits/second of data?

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

#79

Post by tim333 »

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…

pic of the dish for those curious https://www.planetary.org/space-images/the-70-meter-dss-14-a...

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

#80

Post by Retric »

justsomehnguy wrote: post #35
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.

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…

To be clear, the heading of that column is Diameter.

https://www.jpl.nasa.gov/news/nasas-deep-space-network-looks...

As a sanity check, the video says the area of the dish is approximately one acre which would be ~4,046m2 and a 35m radius disk is ~3,850 m^2.

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