1517: "Spectroscopy"

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Kozmo
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1517: "Spectroscopy"

Postby Kozmo » Mon Apr 27, 2015 11:02 am UTC

Image

title="Although right now I'mm more excited about ESPRESSO's radial velocity measurements, so I'm listening to This Kiss, her song about measuring "centrifugal motion" on "a rooftop under the sky"."
Last edited by Kozmo on Tue Apr 28, 2015 7:33 am UTC, edited 1 time in total.

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Flumble
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Re: 1517: "Spectroscopy"

Postby Flumble » Mon Apr 27, 2015 12:00 pm UTC

ps.02 wrote:
Kozmo wrote:Beat me by a second! :)

...By breaking the rules and posting before he or she bothered to think of anything to say.

No one ever listens.
Also, Kozmo, you attached the image instead of linking the original image and, most of all, linking to the page.

Since explainxkcd has only the prelimenary info at the moment, I'll ask here: is there any exoplanet (secondary) transition spectroscopy mission going on? A quick search shows me that ESPRESSO is only concerned with measuring radial velocities (for which we have a much better* tune) and that there are only plans to do ESM in the future.


*more memetic.

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Re: 1517: "Spectroscopy"

Postby Eternal Density » Mon Apr 27, 2015 12:39 pm UTC

Dispite my unfamiliarity with Faith Hill, thus is more readily understood than the previous comic. Still not funny.
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Re: 1517: "Spectroscopy"

Postby Jorpho » Mon Apr 27, 2015 1:17 pm UTC

"The color of infinity
Inside an empty glass
I'm squinting my eye and turning off
And on and on and off the light.
It's for this experimental film
Which nobody knows about and which
I'm still figuring out what's going to go
In my experimental film"

-They Might Be Giants, who are clearly performing some kind of time-resolved solid state laser spectroscopy.

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Re: 1517: "Spectroscopy"

Postby gson » Mon Apr 27, 2015 1:34 pm UTC

This reminds me of an Alanis Morrisette song that I try to live by when working on live electrical equipment, to minimize the risk of the current going through the heart:

"What it all comes down to
Is that everything's gonna be fine fine fine
'cause I've got one hand in my pocket..."

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cellocgw
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Re: 1517: "Spectroscopy"

Postby cellocgw » Mon Apr 27, 2015 1:44 pm UTC

gson wrote:This reminds me of an Alanis Morrisette song that I try to live by when working on live electrical equipment, to minimize the risk of the current going through the heart:

"What it all comes down to
Is that everything's gonna be fine fine fine
'cause I've got one hand in my pocket..."


I guess that's better (for high voltage work) than this song
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Re: 1517: "Spectroscopy"

Postby orthogon » Mon Apr 27, 2015 2:35 pm UTC

gson wrote:This reminds me of an Alanis Morrisette song that I try to live by when working on live electrical equipment, to minimize the risk of the current going through the heart:

"What it all comes down to
Is that everything's gonna be fine fine fine
'cause I've got one hand in my pocket..."

It's best if the other hand isn't stubbing out cigarette, though - especially if the gas fitter is working nearby...
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Re: 1517: "Spectroscopy"

Postby Delta-v » Mon Apr 27, 2015 5:29 pm UTC

What's that second spike to the right of O2, I wonder?

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Re: 1517: "Spectroscopy"

Postby da Doctah » Mon Apr 27, 2015 6:50 pm UTC

They're still doing science songs? I kind of gave up on pop music after Sweet told me that love is like oxygen, and Walter Egan explained magnetism.

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Re: 1517: "Spectroscopy"

Postby Heimhenge » Mon Apr 27, 2015 10:23 pm UTC

Delta-v wrote:What's that second spike to the right of O2, I wonder?


I wondered the same thing. Without a scale on the horizontal axis, no way to be sure. But comparing it to other exoplanet spectra online, I'd guess it's the H2O absorption line.

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Re: 1517: "Spectroscopy"

Postby rmsgrey » Mon Apr 27, 2015 10:59 pm UTC

da Doctah wrote:They're still doing science songs? I kind of gave up on pop music after Sweet told me that love is like oxygen, and Walter Egan explained magnetism.


I prefer maths songs: https://www.youtube.com/watch?v=BipvGD-LCjU

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Re: 1517: "Spectroscopy"

Postby RogueCynic » Tue Apr 28, 2015 4:08 am UTC

gson wrote:This reminds me of an Alanis Morrisette song that I try to live by when working on live electrical equipment, to minimize the risk of the current going through the heart:

"What it all comes down to
Is that everything's gonna be fine fine fine
'cause I've got one hand in my pocket..."
That's better than "Shocker" by Kiss. Do you know the story behind that song? Or was it Motley Crue?

{edit} Found it. Kiss "Shock Me".

http://www.lyricsmode.com/lyrics/k/kiss/shock_me.html#!
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Re: 1517: "Spectroscopy"

Postby Kozmo » Tue Apr 28, 2015 7:36 am UTC

Flumble wrote:
ps.02 wrote:
Kozmo wrote:Beat me by a second! :)

...By breaking the rules and posting before he or she bothered to think of anything to say.

No one ever listens.
Also, Kozmo, you attached the image instead of linking the original image and, most of all, linking to the page.


Oops, sorry. I made an edit so that it's now correctly linked and I won't post anymore with nothing to say. (RTFM is always a good advice but then again do we ever?)

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Re: 1517: "Spectroscopy"

Postby Eternal Density » Tue Apr 28, 2015 1:29 pm UTC

On the topic of sciency lyrics:
Tonight I heard a new jazz song called The Dating Game, which had a verse about a Paleontoligist who was going out with a Marine Biologist, but he wasn't getting very far with her because he was using all the wrong dating methods.
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Re: 1517: "Spectroscopy"

Postby Neil_Boekend » Tue Apr 28, 2015 1:31 pm UTC

H2O isn't as important as O2. If O2 is in an atmosphere there is a process that generates it, as O2 quite quickly reacts with just about anything. There is one quite interesting process that does this: photosynthesys. If there is O2 in a planet's atmosphere the chance that there is life is significantly increased.
H2O just means there once was O2 and H2. With any available ignition source (lightning for example) this turns into H2O. Availability of H2 isn't much of a surprise as there is so much available. If the O2 is reacted to H2O it is not an indication of life.
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Re: 1517: "Spectroscopy"

Postby rmsgrey » Tue Apr 28, 2015 1:48 pm UTC

Neil_Boekend wrote:H2O isn't as important as O2. If O2 is in an atmosphere there is a process that generates it, as O2 quite quickly reacts with just about anything. There is one quite interesting process that does this: photosynthesys. If there is O2 in a planet's atmosphere the chance that there is life is significantly increased.
H2O just means there once was O2 and H2. With any available ignition source (lightning for example) this turns into H2O. Availability of H2 isn't much of a surprise as there is so much available. If the O2 is reacted to H2O it is not an indication of life.


Yeah, an atmosphere not in thermodynamic equilibrium is a dead giveaway that something is pushing it away from equilibrium. In the short term, there are plenty of things that could cause a temporary imbalance (though doing it on a planetary scale is less easy) but life is a major suspect, particularly if the imbalance appears stable - one of the defining properties of life is that it maintains a stable environment away from chemical equilibrium.

Free oxygen is a pretty big hint that there's something that qualifies as life by at least some definitions there.

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Re: 1517: "Spectroscopy"

Postby Jackpot777 » Tue May 19, 2015 7:11 pm UTC

rmsgrey wrote:
da Doctah wrote:They're still doing science songs? I kind of gave up on pop music after Sweet told me that love is like oxygen, and Walter Egan explained magnetism.


I prefer maths songs: https://www.youtube.com/watch?v=BipvGD-LCjU


Radiohead left me VERY confused with this one.

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Re: 1517: "Spectroscopy"

Postby Jackpot777 » Tue May 19, 2015 7:23 pm UTC

Garbage has a song, Why Don't You Come Over? There's a line in it that goes "you taste like toxic poison" and it bugs me two ways.

Poison is, by definition, a toxin. Something toxic is, by definition, poisonous. A non-toxic poison would be like a non-feline cat.

Poison (both the toxic kind and THERE IS NO OTHER KIND, IT'S ALL TOXIC, POISONS ARE TOXIC) doesn't really have to have a taste that makes you say, "this definitely tastes of poison." Bleach is a poison, I guess it would taste like bleach smells (swimming pool water does a little). Cyanide is a poison, and apparently smells like almonds to those that can smell it (40% of people can smell it, so it's like asparagus pee in that regard) ...if you're eating marzipan on cake, you're not thinking, "this tastes of poison" are you?

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Re: 1517: "Spectroscopy"

Postby Neil_Boekend » Tue May 19, 2015 7:27 pm UTC

AFAIK, but I'm no expert, many natural poisons like hops and cafeïne are bitter.
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Re: 1517: "Spectroscopy"

Postby rmsgrey » Tue May 19, 2015 8:43 pm UTC

Generally, people have evolved to a) be able to detect poisons and b) find them unappealing simply because that gives an obvious survival advantage over people who enjoy poisons or don't notice them...

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Re: 1517: "Spectroscopy"

Postby Whizbang » Tue May 19, 2015 8:49 pm UTC

There is also an evolutionary pressure for poisoned things to taste/smell bad. If I am poisonous but don't taste bad, then something eats me and then it dies and we both no longer reproduce. However, if I am poisonous AND taste bad, then the predator will attempt to eat me, find me distasteful, leave me alone, and go off and die, allowing me to continue to reproduce (hopefully).

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Re: 1517: "Spectroscopy"

Postby rmsgrey » Tue May 19, 2015 9:02 pm UTC

Whizbang wrote:There is also an evolutionary pressure for poisoned things to taste/smell bad. If I am poisonous but don't taste bad, then something eats me and then it dies and we both no longer reproduce. However, if I am poisonous AND taste bad, then the predator will attempt to eat me, find me distasteful, leave me alone, and go off and die, allowing me to continue to reproduce (hopefully).


That works for frogs, but not so well for rocks - lead ore has very little response to evolutionary pressures...

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Re: 1517: "Spectroscopy"

Postby danix » Wed May 27, 2015 12:51 am UTC

title="Although right now I'mm more excited about ESPRESSO's radial velocity measurements, so I'm listening to This Kiss, her song about measuring "centrifugal motion" on "a rooftop under the sky"."

This is funny, because This Kiss is one of those rare songs where the lyrics are physically correct. The actual lyric as sung by Faith Hill actually says:
Faith Hill wrote:It's centripetal motion, it's perpetual bliss

Oh dear, a country song that gets science right. Now I need a shower.

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Re: 1517: "Spectroscopy"

Postby ps.02 » Wed May 27, 2015 5:39 am UTC

danix wrote:This is funny, because This Kiss is one of those rare songs where the lyrics are physically correct. The actual lyric as sung by Faith Hill actually says:
Faith Hill wrote:It's centripetal motion, it's perpetual bliss

Huh? In context of that song, I don't see how either centripetal or centrifugal motion actually makes any literal sense. All I get in either case is a vague metaphor, not a force diagram.

So how is centripetal motion "physically correct", or how is it more so than any alternative metaphor? (Or is your point just that centrifugal isn't a valid word describing a real thing? Because it totally is.)

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Re: 1517: "Spectroscopy"

Postby orthogon » Wed May 27, 2015 6:21 am UTC

This is another of those things where different levels of education appear to contradict one another. Initially you hear about centrifugal force as a kind of folk science thing, then you get taught that that's wrong: the force is toward the centre. Later still you find that you can do physics in the reference frame of the moving body, in which case it is legitimate to say that there's a centrifugal force after all. (In my engineering lectures it was described as a pseudo force). If you get into General Relativity, it can be the case that neither force is real: you're in free fall through curved spacetime.

Either way, the two words are typically used to describe forces arising in circular motion: centripetal motion, as referred to by Ms Hill, would be a less interesting phenomenon.
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Re: 1517: "Spectroscopy"

Postby danix » Wed May 27, 2015 7:01 am UTC

orthogon wrote:Either way, the two words are typically used to describe forces arising in circular motion: centripetal motion, as referred to by Ms Hill, would be a less interesting phenomenon.

Duhhhh... I forgot the song mentioned motion, not force. :lol:
Yes, I've also read the related xkcd on reference frames, but still found it interesting that the song used centripetal instead of centrifugal.

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Re: 1517: "Spectroscopy"

Postby Pfhorrest » Wed May 27, 2015 7:08 am UTC

Centripetal motion would be motion toward the center, following the vector of a centripetal force, drawing things closer together, which seems to work pretty well as a metaphor for acting upon romantic attraction (as in a kiss), as used in the song. (Centripetal force would itself be a suitable metaphor for the romantic attraction itself; though really, some universally attractive force like gravity would just work better all around, or even the oft-used [animal] "magnetism").
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Re: 1517: "Spectroscopy"

Postby MakingProgress » Wed May 27, 2015 8:34 pm UTC

rmsgrey wrote:
Neil_Boekend wrote:Free oxygen is a pretty big hint that there's something that qualifies as life by at least some definitions there.


Jupiter's moon Europa's atmosphere contains free oxygen.
Life on Europa is still not a certainty.

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Re: 1517: "Spectroscopy"

Postby Neil_Boekend » Thu May 28, 2015 9:49 am UTC

MakingProgress wrote:
rmsgrey wrote:
Neil_Boekend wrote:Free oxygen is a pretty big hint that there's something that qualifies as life by at least some definitions there.


Jupiter's moon Europa's atmosphere contains free oxygen.
Life on Europa is still not a certainty.

True, that's why I said "pretty big hint". In the case of Europa the presence of oxygen did make the scientists look really hard where that came from. It turns out there is a constant splitting of H2O and the resulting H2 dissapears into space because Europa isn't heavy enough to keep it in the atmosphere. The O2 remains.
I assume the oxygen does not burn with the hydrogen in a chain reaction igniting the whole atmosphere because the atmosphere is so thin (10-12 bar Somewhere on the border between high vacuum and ultra-high vacuum) and it's cold. The reaction of an odd couple of H2 molecules with an O2 molecule does not provide enough energy to react nearby sets because those nearby sets aren't nearby enough.
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Re: 1517: "Spectroscopy"

Postby mathmannix » Mon Jun 01, 2015 6:48 pm UTC

ps.02 wrote:
danix wrote:This is funny, because This Kiss is one of those rare songs where the lyrics are physically correct. The actual lyric as sung by Faith Hill actually says:
Faith Hill wrote:It's centripetal motion, it's perpetual bliss

Huh? In context of that song, I don't see how either centripetal or centrifugal motion actually makes any literal sense. All I get in either case is a vague metaphor, not a force diagram.

So how is centripetal motion "physically correct", or how is it more so than any alternative metaphor? (Or is your point just that centrifugal isn't a valid word describing a real thing? Because it totally is.)


It's a moot point, because she actually does sing "It's centrifugal motion". (source: the internet, plus having heard the song.) Of course, when I sing along with Faith in my car, I always sing "centripetal."
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Re: 1517: "Spectroscopy"

Postby Jorpho » Wed Jun 03, 2015 3:17 am UTC

mathmannix wrote:It's a moot point, because she actually does sing "It's centrifugal motion". (source: the internet, plus having heard the song.) Of course, when I sing along with Faith in my car, I always sing "centripetal."
Whaaat?

At best, it's "centrifigal", which isn't even a word. I mean, "centrifugal" is pronounced "sen-trif-ew-gul", isn't it?

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Re: 1517: "Spectroscopy"

Postby Pfhorrest » Wed Jun 03, 2015 4:12 am UTC

The pronunciation I remember from elementary school was "sen-TRIH-fuh-gl" (pretty close to "sen-TRIH-fih-kl"). I've only heard people say "sen-trih-FYOO-gl" when making a point of distinguishing it from "centripetal" (which in turn I ordinarily hear as "sen-TRIH-peh-tl", and only occasionally "sen-trih-PEE-tl" when making a point of distinguishing it from "centrifugal").
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