
Kids of today...
"The record comes complete with a stylus and is designed to be interpretable by another technological civilisation"
Do they mean my children?
Voyager 2, the venerable space probe launched in 1977, “stopped” last week. Don't dig up your cache of food or prepare to welcome our Oort Cloud Overlords: the pause is a result of celestial mechanics. As the Tweet below explains, Voyager 2 is heading on its merry way and Earth is swinging around Sol as usual. But last week …
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>Can't help but think a modern one would have had it's batteries fail by now and bits starting falling off.
Don't sell modern engineering short. The Mars rovers have had some serious endurance as well and they also aren't close to finished (well one is but still greatly exceeded expected lifespan) so lets wait and see.
The Bubble is a perfect sphere, twelve billion kilometres in radius (about twice as wide as the orbit of Pluto), and centred on the sun. It came into being as a whole, in an instant — but because the Earth was eight light-minutes from its centre, the time lag before the last starlight reached us varied across the sky, giving rise to the growing circle of darkness. Stars vanished first from the direction in which The Bubble was closest, and last where it was furthest away — precisely behind the sun.
The Bubble presents an immaterial surface which behaves, in many ways, like a concave version of a black hole’s event horizon. It absorbs sunlight perfectly, and emits nothing but a featureless trickle of thermal radiation (far colder than the cosmic microwave background, which no longer reaches us). Probes which approach the surface undergo red shift and time dilation — but experience no measurable gravitational force to explain these effects. Those on orbits which intersect the sphere appear to crawl to an asymptotic halt and fade to black; most physicists believe that in the probe’s local time, it swiftly passes through The Bubble, unimpeded — but they’re equally sure that it does so in our infinitely distant future. Whether or not there are further barriers beyond is unknown — and even if there are not, whether an astronaut who took the one-way voyage would find the universe outside unaged, or would emerge just in time to witness the moment of its extinction, remains an open question.
And the world's richest hi-fi nerd, searching for that perfect vinyl sound, in a world where stylus' are no longer available, launches the 'Recover Voyager' programme...
And having brought at least one of them back, he'll retreat to his perfect-acoustics room, fit that last stylus and... listen to his Queen albums!
What? They had a record on it but NOT a stylus? Well there's a good story wasted!
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"What are the chances of anyone ever finding the discs, let alone understanding the instructions to reproduce them?"
Hopefully none whatsoever.
If a civilization has the ability to detect and retrieve a spacecraft from interstellar space (although not apparently to make a record stylus) then we will probably be wiped out. In our own history that's what happened to just about every civilization when a much more technologically advanced one showed up.
"In our own history that's what happened to just about every civilization when a much more technologically advanced one showed up."
But as our own Tim Worstall has recently pointed out (or was it in his book, I can't remember), extra-terrestrial civilisations will not reckon our resources are particularly valuable and nor will they want slaves who are considerably harder to keep running and less capable than the robots ones they already have. Our value to them will probably be purely the entertainment of watching us.
Then there's the fact that unless we grow out of our yobbish ways, we probably won't last long enough to be that advanced, and so we can probably infer a similar constraint on our would-be overlords. That is, their very existence suggests that they are more mature than we are (or were).
There was an Outer Limits episode that addressed the slavery thing. Aliens came to enslave a group of humans, and one of the humans went so far as to point out that this was silly: Any civilization that can build starships has no need of human slaves.
The alien explained it very simply: Their culture considers the use of mechanical labor 'demeaning.' Presumably slaves serve for them as a form of status symbol: Anyone can afford a robot, but having slaves to tend to their needs is the mark of true wealth.
>extra-terrestrial civilisations will not reckon our resources are particularly valuable
It doesn't make any difference. Don't assume that Jean-Luc Picard will be in charge of the starship that comes visiting - it might be Pol Pot.
In our own history thousands of Indigenous Australians were hunted down and slaughtered simply for someone's amusement, as sport. We can be wiped out for not immediately embracing the great god Thaal, or even just so they can try out their new ray gun.
When an advanced civilization encounters a less-advanced civilization, the latter is "wiped out", sort of. In human history, most less-advanced civilizations are assimilated, not totally destroyed. The extent to which a less-advanced civilization contributes to the more-advanced civilization is roughly in proportion to the unique "useful" features of the less-advanced civilization. Why is this a problem? If you are worried about your biological progeny instead of your intellectual progeny, you should be worried much more about the technological singularity or various existential risks instead of worrying about ETs.
http://en.wikipedia.org/wiki/Technological_singularity
http://en.wikipedia.org/wiki/Global_catastrophic_risk
Let's hope it doesn't say "I seem to be having tremendous difficulty with my lifestyle", and ends up in the hands of the Vl'hurgs (although a small dog might once again come to the rescue)
OK, time to go, the one with the cassette tapes of the radio play in the pocket, please
> What are the chances of anyone ever finding the discs, let alone understanding the instructions to reproduce them?
Pretty damn small. In 40000 years, it will come within 1.5 LY of another star. And then continue through interstellar space.
Though not strictly applicable to Voyager, for general context, you might find this analysis of the odds of coming close to a planet or star interesting: https://www.reddit.com/r/askscience/comments/2pe4oj/say_you_had_the_ability_to_fly_a_spacecraft_from_one_side_of_the_galaxy_to_the_other_in_a_straight_line_what_are_the_chances_that_you_run_into_something/cmvvytl
I am amazed to read launched in 1977 and still has years of fuel left. What kind of fuel is used on these craft, is it nuclear or carbon based and how are they actually propelled/steered?
Depending on the application, Voyager has 2 types of fuel.
There's plenty of plutonium fuel left for electrical generation in the radioisotope thermal generator (RTG) until about 2025. The plutonium isotope 238 has an 87.7-year half-life, and Voyager is "only" 37 years old. The 420 watts of electricity from Voyager 2's RTG is down to 258 watts (as of early 2015).
Voyager 2 also had 100kg of hydrazine at launch. This was used sparingly, mostly to set up planetary slingshots where gravity did the most work tossing Voyager from planet to planet. It has used 75kg over 37 years and needs very little to stay oriented in deep space.
> I must admit that most of that is completely, and I mean
> completely, over my head...
I'm curious. What sort of person reads The Register, but doesn't know where Voyager 2 gets its electric power from? (Isn't that in the GCSE science curriculum?)
Seriously, I may have completely misjudged this site's demographic!
"I'm curious. What sort of person reads The Register, but doesn't know where Voyager 2 gets its electric power from? (Isn't that in the GCSE science curriculum?)"
The kind of reader who doesn't study much about space exploration.. and who is probably a lot older than you might think..
Being Scottish we didn't have GCSEs and we certainly didn't have a "science" class. We had Chemistry, Physics, Engineering Drawing and Mechanical Engineering.. none of which included any mention of Voyager 2 or it's power source. At least not when I was in School, although things may have changed since.
@ Khaptain
It's a* thermocouple. A* thermocouple stuffed into a lump of something fiercely radioactive. Lumps of fiercely radioactive stuff are warmer than their surroundings as they're heated by their own decay. Stuff one end of a* thermocouple into a lump of fiercely radioactive stuff and you have simple and potentially** long lasting but feeble power source. Verbose quasitechnical crap like "plutonium-powered radioisotope thermoelectric generators" is just "gosh, aren't I clever" for "a* thermocouple stuffed into a lump of radioactive stuff"
* Actually a great wodge of thermocouples. May as well make as much hay as possible while the plutonium shines.
** Life expectancy depends on the half-life of the source and its products and how quickly the various emissions from all that decay destroy your thermocouple(s)
Well, I didn't. I might have once, but forgotten (until I read this article, which actually mentions the fuel)
I suspect a fair number of reg denizens are pre GCSE for a start.
I took Computer Science, Geography, History, Commerce and Art & Design besides the obligatory Math and English, and on the year GCSE replaced GCE/CSE (it was a disaster, nobody knew What was going on).
I suspect a fair number of reg denizens are pre GCSE for a start.
I'm on the cusp. I sat O level maths, then the following year I sat AO maths and GCSE everything else. I much preferred the O/AO format to the GCSE format. Two years later I sat A level maths, chemistry, physics, biology. But I never had a class called "science".
Narrator: "Time: the future. Place: a distant museum in the Twilight Zone..."
Zog: "This new exhibit came from that crashed spacecraft we found recently."
Zarg: "Any idea what it is ?"
Zog: "We think it's a drink coaster, probably for some form of Djinnan Tonnix as it came with a stick for the olive. Almost certainly a ritual object..."
... and if we're looking at this in proper "Time Team from Cetea Alpha 5" fashion, what we have is a golden disk that has a specially roughened surface to act as a grippy, load spreading surface so a support post doesn't slip sideways and a small nail used to centralise the post on the disk - accuracy was obviously important. From this we can infer the building was 1m high with a domed and thatched roof with finials and gable ends with a nice kitchenette and an area to play Scrabble ... The height shows the population was very short or worshiped on their knees ... Furthermore, since the disk is corrosion resistant gold and was positioned on the ground, the surface of the planet was marshy and soft, and the population couldn't wait to leave (as indicated by the crude drawing of a solar system on the disk).
> "I often think that any modern remake of 2001 (I know, but stranger things have happened) should feature Time Team. "....ere....Tony....have a look at this massive black monolith in trench 3"."
Stranger things may have happened, but such a movie would inevitably resemble 'Hyperdrive' or 'Red Dwarf'.
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Yup still working after all these years. Those guys at JPL did a really good job. Of course having the antennas pointed with nice receivers is also important, given that the receiver isn't at 100%.
Shoutout to Wayne and Len (DSN & Radioscience respectively).
If you add, lets say half a kilo (ounces are only used for buying drugs imo) more plutonium, then you need to add a little more hydrazine for the thrusters to counteract the extra mass.
But then your spacecraft masses a bit more, so the fourth stage needs to be slightly more beefy to get it into the correct orbit, then the third stage has to carry the extra mass of the plutonium, and the extra hydrazine, and the extra fuel in the upper stage, so it needs more fuel, and also extra fuel to lift that fuel...
And so on until your extra half kilo of Pu ends up requiring an extra half ton of fuel in the first stage. The rocket equation is a pain in the bum.
"I think the Americans still use groats and rods in space development. Its the only sign of irony in the whole nation."
Being serious, American rocket scientists managed to produce equations that did not balance their units by the simple expedient of dividing pounds mass by pounds force to simplify equations.
Chances of intelligent life finding it in the next 10,000 years and not already knowing we exist? - practically zero.
We've been broadcasting our position for over a hundred years, electromagnetic waves travelling at light speed, which will be detected by intelligent life long before this physical heap of junk gets anywhere close (and I use the heap of junk term lovingly).
We're looking for intelligent life elsewhere by listening, so if we make the assumption intelligent life would be able to figure out the record and stylus then we can also assume they will have figured out how to listen for us too.
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Unintentional Radio probably only has about 5 light years range. Intentional Beamed transmissions maybe 100 light years range. They are unlikely.
So other than very near stars, SETI via radio isn't going to work. Also civilisations may only use high power transmissions terrestrial less than 100 years and then only local lower power broadcast, Satellite (very little into space) and cable / fibre.
Spectroscopic analysis looking for combinations of chemicals that suggest industrial activity rather than natural sources may find Extra Terrestrial Life, if we have a big enough space telescope. I'll be very surprised if a Radio Search works, even if we currently have 100,000 civilisations in the Milky Way using Radio. (assuming too they were using it x 100s or 1000s or 10,000s of years ago, the disk of the galaxy is about 100,000 light years across).
Space is like a quarantine system, for travel and communication, unless there is some sort of FTL Starships and Ansibles possible.
The Earthlings declared war earlier today when an unusual projectile obliterated the children's gravimetric observatory in the station's East Wing. The stealthy object was travelling at several kilometers per second in normal space, we deduce therefore that it must possess a terrifying ability to open wormholes in a previously unknown, undetectable manner. (The ridiculous alternative theory that it traveled the entire distance in normal space is an even greater threat, as the ability to traverse many light years and still precisely hit a Station is an unthinkable horror) The War Amarda will be on its way as soon as the equations of relative scale are complete.
The craft was pulled over for speeding, and when the aliens went to play the record to determine planet of origin, they couldn't play it because it was encoded with PlaysForSure(TM).
That said, I think that's my new excuse for my boss - I have entered a "Command Moratorium Temperature Stabilization Period", so buzz off.