I am currently drafting a video on Venus, and I would like to be the first person to ever discuss venus without mentioning the phrase "hot enough to melt lead". Is there possibly a more striking metaphor I could use?
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I am currently drafting a video on Venus, and I would like to be the first person to ever discuss venus without mentioning the phrase "hot enough to melt lead". Is there possibly a more striking metaphor I could use?
"Occam" is the name of the alien race that will enslave us all eventually. And they've got razors for hands. I don't know if that's true but it seems like the simplest answer."
Stephen Colbert.
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"Twice as hot as an oven set on High".
"I'm planning to live forever. So far, that's working perfectly." Steven Wright
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That's a pretty cool oven. Venus is ~740K, which would put your oven at around the boiling point of water.
Grant Hutchison
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Lead's melting point is only 601K. Zinc is 693K and tellurium is 723K. One of my post docs involved growing crystals in molten tellurium - on Venus I could do it as a bench experiment.
Sulfur boils at 718K. "Hot enough to boil sulfur"
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Oh I'm definitely using that one; since Hell is defined as a pool of fire and brimstone, Venus is technically hotter than Hell.
"Occam" is the name of the alien race that will enslave us all eventually. And they've got razors for hands. I don't know if that's true but it seems like the simplest answer."
Stephen Colbert.
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But not at Venus's atmospheric pressure, unfortunately. The SVP of sulphur at 740K is only about 1.2 atmospheres, if I'm doing my Clausius-Clapeyron correctly.Originally Posted by Swift
Grant Hutchison
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I guess that “hot enough to melt mercury” may be a little weak.
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As above, so below
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"Twice as hot as boiling water" doesn't have the same impact.
"I'm planning to live forever. So far, that's working perfectly." Steven Wright
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When you consider how cold zero kelvin is compared to boiling water, it's quite impressive, I think.
But my point was really that "double the temperature" is only physically meaningful relative to absolute zero. I'm twice my wife's height if you measure us both starting at her shoulders.
Grant Hutchison
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Yeah, I understood that that was what you meant, though you didn't specify that directly.
As above, so below
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I'm surprised at how many people seem to get a completely wrong impression from the "hot enough to melt lead" comparison, apparently expecting it to mean that the various landers turned into puddles of metal after their arrival. It's apparently no longer common knowledge that lead is one of the easiest common metals to melt?Lead's melting point is only 601K. Zinc is 693K and tellurium is 723K. One of my post docs involved growing crystals in molten tellurium - on Venus I could do it as a bench experiment
Sulfur boils at 718K. "Hot enough to boil sulfur"
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Brass monkeys would presumably be ok at the temperature of melting lead.
Cum catapultae proscriptae erunt tum soli proscript catapultas habebunt.
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Yes, "one of the," but there are others as well. Tin has a lower melting temperature than lead, and yet people don't often take tin as an example; I wonder why. Obviously, mercury is much lower than either tin or lead. And for example, cesium is quite low. I guess that maybe lead is taken as an example because it's a metal that is actually used in applications where it melts (like fuses).
As above, so below
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There was once speculation that Venus might already be doing it:
Kerr, Richard A. "Does tellurium frost Venus's highlands?" Science, vol. 271, no. 5245, 1996
Subsequently discredited, sadly:
Schaefer L, Fegley B. "Heavy metal frost on Venus" Icarus, vol. 168, 2004
Grant Hutchison
Moderator
I remember those papers. There is another type of crystal and coating growing process called Chemical Vapor Deposition that could be related to these possible processes on Venus.
Mostly Harmless"Hot enough to snow lead." Lead sulfide anyway.
Solfe
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Something seemed off about that phrase. I realize this is probably annoyingly nitpicky, but my guess is that the original implied subject is, “the temperature is hot enough to melt...” but we wouldn’t say, “the temperature is hot enough to snow...” So I guess it should be something like, “hot enough for lead to snow”?
Or maybe better, cold enough for it to snow lead?
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Mostly HarmlessPerhaps, the wording should be "There is something off about that Solfe guy."
Solfe
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How about “Hot enough to burn a pizza” pizza oven is about 400 C, 673 K
sicut vis videre esto
When we realize that patterns don't exist in the universe, they are a template that we hold to the universe to make sense of it, it all makes a lot more sense.
Originally Posted by Ken G
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A tandoori oven can hit Venus surface temperatures. So the whole planet is hot enough to cook food tandoori-style.
Grant Hutchison
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Wait, they didn’t? I’m 27 years old and that’s how I’ve been picturing it my whole life!
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They were built from one of the titanium alloys. I haven't been able to find out which of the many options was used, but these metals were chosen because they maintain good structural strength up to 500ºC, so they're not even going to have sagged, let alone melted. Electronics don't work so well at these temperatures, so they fried on a time scale from minutes to a couple of hours.
Hence the plan for what's essentially a steampunk Venus rover, with a Babbage-style mechanical computer.
Grant Hutchison
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I think that is a major reason for the confusion. Sure, it is easy enough to build an object that can take the temperature, but very hard for sophisticated electronics to survive there. So there have been various ideas for high temperature tolerant electronics, refrigerated compartments, mechanical systems and so on, but they all have their own issues (refrigerators need a fair amount of power which isn’t easily supplied, high temperature electronics haven’t been a development priority, mechanical systems can’t be very sophisticated and so on). Therefore, aside from the limited duration probes, not much has happened.
"The problem with quotes on the Internet is that it is hard to verify their authenticity." — Abraham Lincoln
I say there is an invisible elf in my backyard. How do you prove that I am wrong?
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Glass valves (tubes) can survive those temperatures and wire wrap technology is the most reliable so sophisticated electronics should be possible albeit larger and more energy hungry. Many functions can also be done with miniature fluidic devices at very high temperatures.
sicut vis videre esto
When we realize that patterns don't exist in the universe, they are a template that we hold to the universe to make sense of it, it all makes a lot more sense.
Originally Posted by Ken G
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Hotter than a car engine cylinder?
(Actually by a wider margin than I was hoping for, but I can't name something closer offhand that most people would have any concept of...)
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Off topic, but can someone please clarify the timeline of Venus's motion through the sky? As I understand it, it takes 584 days to complete a full cycle, with 260 days as the morning star, 260 days as the evening star and the rest invisible. Is that right?
"Occam" is the name of the alien race that will enslave us all eventually. And they've got razors for hands. I don't know if that's true but it seems like the simplest answer."
Stephen Colbert.
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Venus orbit is about 225 days while Earth is about 365 days. Venus is nearer the sun so viewed from here it is always nearish the sun, either to “left or right” so as we spin, Venus appears either ahead of or behind the sun, or of course too close to the sun to see. So, if you imagine the alignment with Venus conjunct sun, Venus close to Earth, Venus then apparently moves to the right of the sun and “rises” before the sun. It then takes longer than the Venus period to get to alignment again which is where you get 584 days. About half way through, Venus is on the other side of the sun, (and so much further away), after that, Venus seems to move to the left, therefore setting after the sun as seen from here.
sicut vis videre esto
When we realize that patterns don't exist in the universe, they are a template that we hold to the universe to make sense of it, it all makes a lot more sense.
Originally Posted by Ken G
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Think it is only just cooler than a campfire. A very dull red flame would be about 500C (although the 'temperature' of a fire varies by a huge amount depending where you take it so this may be a poor comparison)
Mostly HarmlessEven NASA said, "Hot enough to melt lead." This is an impossible task. There is no changing that metaphor!
That radar target system for data "transmission" is pretty neat.
Solfe
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