Rusty scuppers?
Or just poor planning?
The venerable Voyager 2 spacecraft is currently more than 19 billion kilometres from Earth, travels at 15 kilometres per second and talks to NASA’s Deep Space Network (DSN) at a torturously slow 160 bits per second. And today chatting to the probe got a little harder when the DSN node scheduled to log on – the Deep Space …
"which would reduce your "listening" ability."
Not as much as you might think.
Every dish I ever came in contact with had weep holes in such places. From what I was told, virtually every such dish is pointed straight up in "storm lockdown" conditions, and seeing as storms are often associated with cold fronts, cold enough to freeze any standing water, they attempt to drain it away as fast as possible rather than ice things up, potentially buggering up delicate adjustments.
Canberra doesn't get much frost (if any at all - normally it barely touches freezing during winter) - more importantly it doesn't get much rain when it's that cold and it doesn't get much in the way of high winds either
weep holes are fine, but they may drop water from the subreflector straight down onto the receiver electronics - which is "undesireable". Tipping it out avoids the sensitive bits
It doesn't take "much frost". One good freeze is enough.
Said weep-holes direct the water away from the sensitive bits. Kinda like your roof & down-spouts.
Besides, the receiver electronics are sealed in weather-proof boxes. Not even NASA is stupid enough to funnel rain water directly onto the circuitry.
"Not even NASA is stupid enough"
Wait what? I thought we were fixing NASA's design flaws.
Are you telling me that, bear with me here, NASA may have thought about rain when they designed these dishes?
Say it's not so.
Here I was ready to expose my genius level skills by denigrating those stupid engineers and scientists who have deployed the largest dishes all over the planet, and now you tell me they actual might know what they are doing?
This keyboard warrior is so disappointed about a missed opportunity. Anyone got any suggestions for other areas I can excel in? I hear vaccines are big right now. Maybe I'll mosey on over to the immunology department and use my genius to point out their obvious errors.
"Canberra doesn't get much frost (if any at all - normally it barely touches freezing during winter) - more importantly it doesn't get much rain when it's that cold and it doesn't get much in the way of high winds either"
I live in Canberra. We get LOTS of frosty nights every winter, some as low as -8C. We also get severe thunderstorms (like the one yesterday which filled up the dish and flooded my back yard) which bring torrential rain and very high winds.
long ago, I also lived in Canberra and experienced torrential rain storms that flooded and closed main roads in the south (Woden Valley). Once such event caused cars to be swept away with at least one fatality.
The frost: removing the ice from your windscreen is a regular morning chore in Canberra...
Surely it just depends on the wavelength of the signals you intend to use? In the same way as microwave oven doors have holes in the shield so you can see the food, but the holes are sized to not allow the microwaves to escape.
OK, that might make the drainage inefficient and prone to blockage, in which case a small pump might prove useful. Keep the 'pause operations and tip the dish' procedure as a reserve in case the pump fails.
"Never underestimate the bandwidth capability of a station wagon full of mag tape." is a quote often attributed to Tanenbaum in 1996, but it was a common expression when I was at DEC long before that ... and I remember a similar comment from a student at Stanford in the early '80s when a professor expressed surprise at one of the vaxen already running the latest BSD build, released just a few hours before. Conversation went "How on earth did you get that code across the network that fast?" answer was "My motorcycle's latency might be sub-par, but it still has a much higher bandwidth capability than your network!".
I wonder if they use a phone stuck into an acoustic coupler like what we did in the early 80s? Always used to amaze me how much info you could actual send/receive over a 70/300 modem. Used to send small circuits to an IBM somewhere and get reams of line printer plots to check over the next day!
I'm pretty sure you're joking, but the answer is no. In fact, the extremely weak signal from nineteen and a half billion miles away (three quarters of a light-day) is pulled out of background noise by some very clever equipment and programming.
In the other direction, we can broadcast at pretty good power, so the Voyagers receive a clear signal.
The numbers with either Voyager craft have always seemed mind boggling to me.
It's hard to visualise how far 19 billion km is or even how much has occurred on Earth since the crafts were launched. Or a speed of 15 km/sec meaning I could get to my office in under 3 seconds. Hard to imagine.
The fact a comms link is even possible is astonishing. Yet it also beggars belief we can't connect certain people on Earth given this is actually possible so far away from it.
It's hard to visualise how far 19 billion km is
Some 480000 times the circumference of the Earth at the equator. Going around 13 times _a day_ it would take you 100 years to cover those 19 billion km.
Or a speed of 15 km/sec meaning I could get to my office in under 3 seconds.
At that speed I don't think you'll be Gatso-ed, at least not with your license plate sufficiently unblurry, but you do have to start braking in time so as to not smash in to the wall at the far end of the parking lot.
"It's hard to visualise how far 19 billion km is"
Here's a bit of a visual aid ... it only goes out 5.9 billion km, though. Extrapolate :-)
At 15km/sec getting to your office would indeed take 3 seconds
Sadly (and taking that you're around sea level) that speed in the atmosphere at that height would cause quite a large explosion..... maybe a few melted bits of the engine would land on your desk.... but I would'nt think so.
Still might provide a few headlines "Man attempts hypersonic commute to work... physics says no"