Difference between revisions of "Talk:2009: Hertzsprung-Russell Diagram"

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:Worked it out, it's referring to the colour temperature. [[User:YM Industries|YM Industries]] ([[User talk:YM Industries|talk]]) 05:24, 21 June 2018 (UTC)
 
:Worked it out, it's referring to the colour temperature. [[User:YM Industries|YM Industries]] ([[User talk:YM Industries|talk]]) 05:24, 21 June 2018 (UTC)
 +
::Right.  The color temperature of an LED bulb can be much higher than a blackbody of the same power and area because it emits in only a small spectral region.[[Special:Contributions/108.162.238.47|108.162.238.47]] 05:32, 21 June 2018 (UTC)
  
 
I'm pretty sure there shouldn't be a table in the transcript? I've moved it, but now the table needs to be filled and the transcript needs some work. [[User:Herobrine|Herobrine]] ([[User talk:Herobrine|talk]]) 03:10, 21 June 2018 (UTC)
 
I'm pretty sure there shouldn't be a table in the transcript? I've moved it, but now the table needs to be filled and the transcript needs some work. [[User:Herobrine|Herobrine]] ([[User talk:Herobrine|talk]]) 03:10, 21 June 2018 (UTC)
  
 
Venus' temperature is correct. Randall is using planetary equilibrium temperature <ref>https://en.wikipedia.org/wiki/Planetary_equilibrium_temperature</ref> [[User:Astronorn|Astronorn]] ([[User talk:Astronorn|talk]]) 04:56, 21 June 2018 (UTC)
 
Venus' temperature is correct. Randall is using planetary equilibrium temperature <ref>https://en.wikipedia.org/wiki/Planetary_equilibrium_temperature</ref> [[User:Astronorn|Astronorn]] ([[User talk:Astronorn|talk]]) 04:56, 21 June 2018 (UTC)

Revision as of 05:32, 21 June 2018

How the heck is a lava cake more luminous than a campfire? 108.162.219.28 (talk) (please sign your comments with ~~~~)

It's Lava Lake, as in a large puddle of lava.Cgrimes85 (talk) 15:45, 20 June 2018 (UTC)
Now the real question is, Why isn't lava cake included on the diagram?!?! Veleek (talk) 23:54, 20 June 2018 (UTC)

As it's a logarithmic scale, is it more correct to say the plot been expanded to 1 on both axes? Cgrimes85 (talk) 15:47, 20 June 2018 (UTC)

It seems Randall thinks an astronomer is about as bright as a lightbulb, probably due to the Hertzsprung-Russell diagram itself! Ianrbibtitlht (talk) 15:52, 20 June 2018 (UTC)

A daily food consumption of average human is about 100W when spread out over 24 hours
It might actually be about that bright, but in the infrared spectrum. http://elte.prompt.hu/sites/default/files/tananyagok/InfraredAstronomy/ch01s04.html 108.162.246.89 20:54, 20 June 2018 (UTC)
But they are no where near as hot!
You seem to overestimate the attractiveness of most lightbulbs. I've only seen a few that I would consider really hot.

172.69.198.10 20:57, 20 June 2018 (UTC)

While wattage is used as an informal proxy for bulb brightness, there is not a 1-to-1 relationship between power consumption and light output. Incandescent bulbs in the United States were commonly labeled with both watts consumed and lumens output to aid consumers in choosing efficient bulbs.

Ivanpah doesn't have a salt tank. Presumably he meant the boiler, and/or was confusing it with Crescent Dunes. Wwoods (talk) 17:29, 20 June 2018 (UTC)

I understand the explanation, but what's the joke?

The title text says "The Hertzsprung-Russell diagram is located in its own lower right corner, unless you're viewing it on an unusually big screen." But it's clearly on the top left corner... Am I missing something? 108.162.219.106 18:47, 20 June 2018 (UTC)

Why would it be at the top left...? The diagram itself is not particularly luminous, so would not be at the top, and its apparent temperature is quite low, so it would not be on the left.


Why is a blue whale considered more luminous than a campfire? Blue whales don't generate any light.

In one of the interesting parts of this diagram not that many mundane objects (or at least smaller than earth objects) are much hotter than most stars (surface temperature)... Not mentioned now.--Kynde (talk) 20:33, 20 June 2018 (UTC)

I think the current explanation is still taking some of the graph too literally, thereby missing some of the jokes. After all, Randall creates comics, sometimes using innuendo or subtlety to make a point. I still think some of the items on the graph are plotted using luminosity as a measure of "brightness" in the sense of smartness. No offense intended, but he must have had a reason for including France below the planets and the blue whale above the astronomer. Furthermore, the title text is likely talking about the actual HR diagram not being very "bright" in the same way the astronomer is in the lower-right corner of the graph, except when it is displayed on a jumbotron. If you're an astronomer, you might not like hearing this, but the meaning of the HR diagram is difficult to grasp correctly. To leave out any mention of smartness is likely missing the most significant jokes in the comic. Please feel free to disagree, but remember it's still just a comic! Ianrbibtitlht (talk) 00:37, 21 June 2018 (UTC)

More specifically to my point, this part of the explanation
"the title text notes that the screen displaying the diagram would probably be plotted..."
is not correct. The title text states the diagram itself would probably be plotted in the lower-right corner, not the screen displaying it - the screen was only related to the second part of the title text! This IS the primary joke in the comic and likely why Randall is making fun of it in the first place. This is also likely the reason for the astronomer to ALSO be plotted in this corner - I doubt that is just a coincidence. Maybe Randall was too subtle for his point to get through to readers! Ianrbibtitlht (talk) 04:37, 21 June 2018 (UTC)
Just in case I'm also being too subtle, I think Randall is saying that the HR diagram is neat to look at (as in really cool) but also stupid (as in not very bright), putting it in the lower-right corner of itself (cool and dim)! There, I said it! Ianrbibtitlht (talk) 04:45, 21 June 2018 (UTC)

How come this diagram says an LED bulb is hotter than a lightbulb, and both are hotter than a campfire? That doesn't seem right. YM Industries (talk) 01:49, 21 June 2018 (UTC)

The confusion is coming from the fact that the arrow at the top is pointing toward lower temperatures. I'm not sure if this is intentional, or if it is a mistake, but seems to be confusing a lot of people (including myself until I read the actual numbers)Probably not Douglas Hofstadter (talk) 03:09, 21 June 2018 (UTC)
I noticed that the arrow was pointing in a confusing direction, but LED bulb is to the left of the campfire. The diagram clearly says it's hotter. I'm very confused by this comic. YM Industries (talk) 05:22, 21 June 2018 (UTC)
The location of the LED and Lightbulb temperatures may be related to the actual light source points of these objects (diode junction and wire filament) rather than the outer shells that we can touch. I don't know enough about their internal temperatures to say for sure, but that might explain their positions. Ianrbibtitlht (talk) 05:05, 21 June 2018 (UTC)
Worked it out, it's referring to the colour temperature. YM Industries (talk) 05:24, 21 June 2018 (UTC)
Right. The color temperature of an LED bulb can be much higher than a blackbody of the same power and area because it emits in only a small spectral region.108.162.238.47 05:32, 21 June 2018 (UTC)

I'm pretty sure there shouldn't be a table in the transcript? I've moved it, but now the table needs to be filled and the transcript needs some work. Herobrine (talk) 03:10, 21 June 2018 (UTC)

Venus' temperature is correct. Randall is using planetary equilibrium temperature [1] Astronorn (talk) 04:56, 21 June 2018 (UTC)