A signal from venerable space probe Voyager 2 reached Earth today, acknowledging that the spacecraft has received its first command since March 2020 and had reset internal clocks as instructed. Voyager 2 has sent data home since that date, but the ability to send commands to the probe was temporarily offline due to a refresh …
As I type this, I'm watching a live broadcast of the launch of an unmanned Russian space freighter to the International Space Station on YouTube.
When Voyager 2 was launched, there was no internet (there was ARPANET, but no TCP/IP), certainly no YouTube, and Soviet launches were usually observed live only by American spy satellites.
A permanent space station had been a fantasy since the mid-'60s, but nobody would have ever predicted it would have been assembled by an international effort, including a significant portion from the Russians.
I have a machine that can "print" 3D objects that I design in a CAD program. I have 2 high power long range electric motorcycles in my 3-car garage. I have home-made temperature sensors scattered about the house communicating wirelessly to a desktop running a UNIX-like OS developed by the world community. It's got 32 fricking gigabytes of memory, is water-cooled, and doesn't even have spinning disk drives or tapes.
I didn't even have my first computer until 1979 and it was a TRS-80 Model I Level 1 with 4K RAM.
I have a color laser printer that I bought for $300. In 1977, the new Xerox 9700 cost $500,000. The HP LaserJet wasn't until 1984, cost $3,500, and sure as hell didn't do color!
I have a small handheld computer that can talk to anyone in the world, and navigate me from place to place, as well as keeping track of my bank accounts and tons of other information. Plus it can play Solitaire.
Yeah, if you'd told me about all this in 1977, I probably would have decked you.
"That's not a car, that's a flying billboard. It's a fucking advert. An eyesore. Pollution. In space. Musk should be ashamed of himself, but I doubt the twat knows how."
On the other hand, it made prime time news around the world and got people interested in space who, until then it had all been a bit "meh".
Pollution is a much different situation than eyesores. You can't have an invisible eyesore.
And a half-mile off trail in Yosemite is somewhere people are likely to see it. A small object millions of miles away from any human, is somewhere people will never see it.
So litter is OK if nobody sees it? Is it OK if only one person sees it? Two?
And "small" litter is OK? At what point is it too big? Matches? Fag ends? Used chewing gum? Gum wrappers? A dead car pushed over a cliff where nobody is likely to run across it?
"And a half-mile off trail in Yosemite is somewhere people are likely to see it."
Not really. I was some 20-odd miles Northish from the Valley, well above the tree-line, maybe 10 or 12 trail miles and 4,500 feet of elevation change from the nearest trailhead. It's not exactly a place your average car "camper" would venture. I had never seen any trace of people there before.
Yes, I packed out the trash. One wonders why the idiots who carried an 18-pack of cheap beer and four foot-long Subway sandwiches uphill somehow managed to lose the energy to haul the empties out downhill.
 Busch Light. WTF? Probably under-age frat-boys trying to be cool ...
"Have you seen how people drive on roads?? Do you really want them to be texting while flying?"
On the first hand, why not? Collision avoidance is a job for sensors, relays and "am-i-doing-a-stupid?" softwares.
On the other hand, no, people can't be trusted to keep hold of their precious Veblen Goods while twitting on the pot, dropping one from several kilometres high would test the durability of even a Nokia.
On the gripping hand, there is the constant dread every politician and pontiff must have of disappointed parishioners with grudges and full recta. Sticky commentaries on their job performances delivered from on high may be funny the first few hundred times but would almost certainly get old. Deliveries of things other than sticky blobs, for example fragile bags of contraband pharmaceuticals to enhance the mornings of working politicians or other chemicals to ruin those same mornings, would be rather less amusing.
On the invisible, psychic hand: there may be reasons other than economics, engineering limitations and the Laws Of Physics why flying cars, personal airships and jetpacks are still hypothetical. At least a few of the Elite must be able to see the inevitable consequences of millions of MAGArats and their enemies jousting in the clouds.
6/1/21 could have been very entertaining had everyone had access to cheap, personal flying machinery.
Well, I usually go by by the SRI packet radio van at the end of '77 for the beginning of the Internet, and that TCP was split into TCP/IP in '78. Those are just my personal touchstones.
I was originally on BITNET during college, UUCP provided by the university afterwards and a little FIDONET, and then I got an actual dialup connection from a local provider.
And nuclear power was contributing to the GB grid in the 1950s. But for the efforts of self-styled environmentalists who
unwittingly unthinkingly promoted fossil fuels there would have been a lot more.
Today, of course, to adapt a quote from a yachtsman, part of our electricity is supplied by nuclear fusion-powered gas turbines.
...and we have medical imaging and diagnostics that are so advanced even Star Trek couldn't envision them.
We have the ability to manipulate the very stuff of life - we know our own genetic sequence, can call out rogue genes and do something about common cancers before the fell us. And when a new threat emerges (I'm looking at you Covid-19) we can sequence that in less time than it took to build the first Liberty ship.
So, world hunger, climate change or zombie apocalypse, we've got this. Trust me - I'm an engineer.
Errrm... gonna err on the side of caution.
Mainly because I work with a lot of engineers (some of whom have issues with some things now considered to be basic PC use, but I digress..) and I don't trust many of them.
Especially since I was asked did I happen to know, offhand, the tensile & breaking strengths in Netwons per square inch; of the patch cables we had.
When I asked why, I was give an answer which chilled my (admitedly shrivelled IT) soul: "Building a desktop Trebuchet...
Where are you running off to?"
XD - icon because it really matches...
I'm not letting a bunch of civil, mech, electrical, process & HVAC engineers anywhere near the door to our comms rooms, let alone in them! XD
Besides, I prefer the BOfH's approach. I tell people that voltage is a great educator.
It has positives and negatives though. But HR says I have to be nice, so now I let them choose which teste / nipple will be positive and which will be negative...
Didn't they have iPads on the ship in 2001? I seem to recall hand-held devices with touch screens.
"In 2011, an unusual piece of evidence was presented in court in a dispute between technology giants Apple and Samsung over the latter’s range of handheld tablets, which Apple claimed infringed upon the patented design and user interface of the iPad.
As part of Samsung’s defence, the company’s lawyers showed the court a still image and clip from Stanley Kubrick’s 2001: A Space Odyssey (1968) showing the astronauts played by Gary Lockwood and Keir Dullea eating while watching a TV show on their own personal, mini-sized, flat-screen computers."
To borrow an advertising slogan for conventional lawn mowers... , "It's a lot less bovver than a hover"
Joking aside, it's still relevant in the right environment for the design.
The sole remaining example of a cross-channel car-carrying hovercraft, "The Princess Anne" is at the Hovercraft Museum at Lee-on-Solent in Hampshire...
She was singing about pocket calculators, in all their very red LED wonderfulness. The HP-35 came out in 1972, the cheap-as-chips TI-30 came out in '76. Also by 1976, I was selling fully assembled calculator kits, mostly HP, Heath and Sinclair, to students at Stanford and Berkeley at what I thought was a fairly hefty markup.
The song is suggesting that a kid could do a lot better than pumping gas for a living, maybe purchasing a calculator could get him started back on the intellectual pursuits he demonstrated in school ("try to do what you used to do").
Last saw Deborah back in '99 and she looked fabulous from the cheap seats. "Picture This" of course envisaged the multi-lensed smart phone, for how else would it work in "total portrait", in the shower, from the "room with a view" and during a a "day in December"? No doubt about it, she's a demanding photographer. Where was I? Ah yes, I think I'll adjust my f-stop....
In '74 as a youth, I had a part-time job repairing Canon calculators for a dealer. I still remember some of the machines having mechanical delay lines - a rather large tin box soldered onto the PCB, I assume filled with wire based on the schematics - acting as "memory". Didn't hold the data for very long and it was serial in bits, run around the wire for a while, and then serial out bits, but it took long enough to be useful.
Damn, did I really work on that stuff? I haven't thought about that in a really long time.
a rather large tin box soldered onto the PCB, I assume filled with wire based on the schematics - acting as "memory". Didn't hold the data for very long and it was serial in bits, run around the wire for a while, and then serial out bits, but it took long enough to be useful.
Indeed. In our collection of Antediluvial Tech there's an Olivetti 101, the world's first programmable desktop calculator. Its memory is such a delay line.
Why does the spacecraft go into sleep mode if it doesn't hear from Earth? If there's nothing left on the planet besides cockroaches and radioactive ash then chances are good that it will never be contacted again ever. I suppose this could come in handy if the main radio dish gets taken out by some space rubble and the science instruments can be spared while waiting for a replacement to arrive. (Or the spacecraft gets disoriented and attempts are made to reestablish contact, boring, blah blah).
In Stephen Baxter's 'Titan', there's a fascinating paragraph about these modes, as well as what will happen to ancient spacecraft drifting across space.
....an expected command from Earth did not arrive.
Voyager had been designed to operate during an extended life-rime and at a great distance from
Earth, with an hours-long downlink-uplink communications round-trip time. Since contact with the
ground would not be continuous, the spacecraft could know if it had lost contact with Earth only if it
missed an expected command. So the software embedded in its engineering flight computer
contained a command loss subroutine. When the command did not arrive on schedule, an internal
alarm went off.
The computer went into an algorithm designed to protect the spacecraft and its mission. First
Voyager was placed in a stable, passive state. Then, for two weeks, Voyager waited for the ground
control to solve whatever problem had arisen on Earth, and to send the spacecraft a new command
sequence. The basic design assumption was that the control centers would be sending a stream of
commands, frantically trying to get the spacecraft's attention.
When no command sequence was received Voyager assumed the fault was with itself. It went
through an emergency routine, in a bid to reestablish contact with the Deep Space Network stations.
The procedure worked in a loop. First the computer tried to figure out whether the craft's radio
antenna was still pointing at Earth. Voyager had sensors to detect the sun, and fixed, bright stars
Jike Canopus; it knew where it was in three-dimensional space. The craft was smart enough to
know where Earth should be, relative to the fixed stars, at any moment during the extended mission.
So the software checked the angles, and the antenna was pointed at Earth.
Still no commands were detected.
Voyager's next assumption was that its radio receiver was dead. So it shutdown its primary radio
and turned on its backup receiver. It broadcast telemetry to Earth, indicating what it thought might
have happened. There was no response from Earth.
Voyager went back to the beginning of the loop, and began the reacquisition process once more.....
... Like a desiccated dragonfly corpse adrift on a breeze, Voyager One circled the heart of the
Galaxy. At last the slow sublimation of metal caused the aluminum structure to weaken to the point
where its ten-sided framework collapsed. The fragments of the spacecraft - instrument booms and
power generator, pitted and tarnished, metal walls reduced to a paper thickness - drifted away from
each other. The directional antenna, as thin as a dried autumn leaf, crumbled away from the curving
spars that supported it, so that the ruin of the spacecraft was surrounded by a cloud of glittering
In the extremely likely scenario that the Earth is rendered silent by human actions, Voyager should assume that she, herself, is utterly safe as nothing will be coming from Earth for quite some time, if ever and aliens are a poor bet at best.
Whether this translates to "keep sending data as per my last instructions" or "go dark and silent while collecting data for future contacts" or something else depends upon the priorities of the original mission planners and their generations of successors.
When Man takes out his only home, Voyager is rather well insulated from the action by a considerable layer of distance. Few, if any, humans are going to bother to try to hit her with anything when they could be using anything offensive to annihilate one another.
It may be that man's little flotilla of robots will be the last functioning bits of high technology left in the universe at some point.
A thought both thrilling and deeply sad.
One does wonder... we lose contact in 2032 or so, per the article; in 2050, we build a fusion-powered kilometer-diameter radiotelescope in orbit with enough oomph to re-establish contact. Surely we can upgrade our communications abilities enough to keep up with increasing distance and the 38-year half-death of Pu-238!
Nice thinking and I guess that's kind of what we've done already. But, there will soon come a time when voyager simply doesn't have enough power on board to stay powered up, regardless of any spare power to beam out of the antenna. At that point, beaming more power from earth or having a bigger dish won't help you as there'll be no live circuits on board to recieve or transmit anything.
As I write this, I feel sad.
NASA plans to shut down more instruments to keep the Voyagers online for as long as possible, but the probes look likely to lose touch with Earth in around 2032.
By then, they’ll be 55 years old - half a century longer than the duration of their planned mission. And an even mightier symbol of human ingenuity and curiosity than they are today. ®
Much more importantly, are we prepared for the return of Voyager?
When you consider just how old the technology is now and the fact that it was probably not cutting edge at the time of launch (risk is everything) is is pretty remarkable how long both of the Voyagers have continued to run.
One has to wonder New Horizons would achieve the same longevity.
Is that at some point before 2032, due to people not paying to maintain the ground equipment, we'll lose contact with it, at which point it will spend a few years crying out to us in the dark before finally its power runs down. Voyager may outlive the ability of the people who launched it to communicate with it.
Only as a non-functioning spacecraft. It will run out of power.
It depends on the energy provided by the decay of a radioactive isotope. The nature of radioactivity means that in order to provide that energy the isotope decays into something else. As time goes on there's less radioactive material and therefore less energy. In this case the half life - the time at which only half of the isotope previously there is now left - is 38 years. 38 years was generous in terms of the planned mission. In terms of an extended mission it isn't quite so generous. As it loses power more and more stuff has to be shut down to make use of what's left. At some point everything's gone and it becomes a non-functioning spacecraft.
Kids today. You have to explain everything.
"It will run out of power."
Which makes me think a little. Why? Why not replace the RTGs? Take a look at this picture, the RTGs are the three prominent canisters. How difficult would it be to replace them as a unit? Here's some perspective on the complete package.
Shirley we've done far more difficult robotic repair jobs in space. And certainly more costly module replacement. We could stack two loads of fuel in orbit, enough to accelerate to a fast enough speed to intercept, and then to slow down to match speed. G forces are nearly unimportant with no squishy meatware to worry about. Likewise food, water, etc. Simply latch onto the probe, unplug the old units and plug in the new.
Yes, I know, the devil is in the details ... but it's only rocket surgery. (It's also low on hydrazine ... obvious answer is obvious.)
Which brings up the question: Why bother?
To which I answer "Why not?" ... it'll be a much better, and longer lasting, PR stunt than that Musk twat littering all over LEO just so survivalists can upload cute cat videos from their supposedly off-grid homesteads. With all of the on-board science packages warmed back up and functional, who knows what we may discover?
If we could justify the repair mission on cost and time, and perform the engineering, it would surely be more economic to just send the new spacecraft with new and more efficient and more sensitive instruments, and bigger RTGs and not to bother with the 'upgrade' of the Voyager at all. Now that we know we can send a probe that deep into space, we could design one to be far more effective at recording and sending data back to Earth and with experiments designed for that mission.
We love Voyager 2, but every now and then you have to say 'goodbye', sadly.
"it would surely be more economic to just send the new spacecraft with new and more efficient and more sensitive instruments"
But would it? Voyager has been putting along, merely going about it's business for half a century. Changing the battery and topping it up with
gasreaction mass should give it another half century or more. The only new bit of kit needed would be the robot to make the swap itself. All the scientific instrumentation is already in place, it just needs power.
Sure, throw in a better radio and antenna, some more modern gyros, perhaps a couple of newer design cameras at various frequencies ... but all that stuff is already available, off the shelf. Most of the robotic mechanic already exists and is proven, too. So no R&D costs, other than mounting. Note that any newer kit could stay bolted to the courier rocket, no need to bolt it to Voyager itself.
The total mission package could be put together for not very much money, as such things go ... but think of the shot in the arm it could give to the space program as a whole. Call it a "rescue mission" and watch kids gravitate back to having an interest in the space program again. Purely emotional? Yes! But is that entirely a bad thing?
No, I am describing replacing the battery in my transistor. The guts of the thing are just fine, it just needs power.
(I almost never use Trigger's Broom ... I prefer the original, Arkwright's brush, from a decade and a half earlier. But even that is new-fangled, when you remember the Ship of Theseus.)
That's an oddly pessimisstic view given the context of the article. The whole point was that the equipment previously lasted 40+ years, and has just been updated specificaly to allow contact with Voyager to continue. It seems a bit odd to assume that it will suddenly all be abandoned within the next decade.
Yes, it is pessimistic: I didn't say it will happen, just that, given what happened quite recently in Puerto Rico, optimism about our ability to maintain systems like this is obviously not always justified. Apart from anything else: we have precisely one antenna which can talk to it: a single bad event can mean this is lost.
I remember reading in Look and Learn in the late 60s about how the Solar System planets were going to line up soon in a way that wouldn't repeat for hundreds of years and that NASA was evaluating proposals for a "grand tour" mission. Here were are. I am much older and greyer and the grand tour is still going. It actually brings a lump to my throat.
As someone who has worked with 10m + satellite antennas on earth, I raise a beer to the guys working on this. Setting up and aligning an antenna of that ilk is difficult enough when the satellite is just above your head ( c. 36,000 km, so relatively speaking) and in a relatively fixed position with a beacon transmitter running 24/7. Trying doing that with an antenna of that size, to a spacecraft which is an incredibly small target, whilst the earth is rotating such that the target is only in your line of vision for a few seconds, and then waiting 35 hours to see if you got it right (and make sure the antenna is still on target after 35 hours!). It is just utterly mind blowing! I also raise a beer to the guys who designed the antenna and gyro system and transponder onboard Voyager that is it is able to keep its antenna accurately pointing to earth with that incredible amount of accuracy.
Mindboggling. Just mind boggling.
Seems to me that the Voyager 1 has "officially entered Interstellar Space" about half a dozen times now. It depends on what you mean by interstellar. Context matters.It's the voyagers that are key in helping us define the boundary of the solar system, defining what interstellar space is. They are their own worst enemy in this aspect.
When NASA said they were resetting the clock, I immediately thought of relativity. Since time is relative, I wonder how long the voyager probe thinks it has been in space versus how long we think the probe has been in space. If it had an internal calendar, what day is it to the voyager probe?
Although 15km/sec is incredibly fast for us small Earthlings, it is only 0.005% of the speed of light, which is far below the speed where any relativistic time dilation would start to have an appreciable affect.
However, it is true that its internal clocks will have been running faster than any on Earth, but that is as a result of it being far away from a gravitational field (in our case Earth's), rather than the speed it is moving at.
Let's work it out! Just accounting for special relativity and assuming the speed it's going at now is the same speed it's always been going at (not quite true but it'll do for now), relative to earth.
The Lorentz relativistic factor sqrt(1-(v/c)^2) is about 1.3x10^-9. So in 44 ish years since launch, about 1.4bn seconds have elapsed, so that's a clock difference of about 1.8 seconds.
I believe that the GR effect may well be dominant, and I'm pretty sure it is dominant now in any case, so in due course it will be dominant overall if it is not already. I think the overall difference is some small number of seconds (less than ten). If I was more awake I'd try to work it out...
I'm not no sure. GR causes time to run more slowly in high gravitational potentials, so voyager's clock will actually be running slower due to special relativity but faster due to general relativity, as it speeds away from the sun.
Struggling to remember it here but I've a nagging suspicion that the two effects might be cancelling out somewhat. From memory, the time dilation effect due to GR is equivalent but opposite to the time dilation effect due to special relativity for a body falling into that gravity well from infinity. Or in voyager's case, due to being launched out of the [sun's] gravity well at escape velocity. Voyager is destined to leave the sun's gravity well so it's obviously going faster than escape velocity, so I suspect time dilation due to special relativity is a greater effect here than due to GR. I think...