The bubbles on top of my pot of coffee become rainbow when I blow on them
  • 398 points Dazzling-Adeptness11

    Soap residue? Oils from the coffee?

    parent
    296 points a_weak_child

    Blowing on them bends the bubbles, refracting the light relative to the eye of the observer. Coffee grounds often have these rainbow bubbles doesn’t have to be soap.  

    parent root
    41 points George2110

    Also, If the bubble turns black just before popping, it means the film is so thin it no longer reflects visible light.

    parent root
    20 points Rooilia

    The bending itself isn't the reason, but thinning out the bubble so far that the thin film begins to refract light.

    That way you get anodizes tools and carabines for hiking too.

    parent root
    4 points DervishSkater

    Yes, but because of the oils as a film…good coffee is well oiled when brewed (properly)

    parent root
    4 points a_weak_child

    Exactly. Upvote cause this is part of it too. I am a long time coffee drinker and noticed it once started buying the best beans from a local roaster (organic, fair trade, properly roasted etc). 

    parent root
    0 points PhD_Pwnology

    Having made coffee for about 10+ years i can honestly say I've never seen this, ever. Is this a rare event?

    Looks like soap residue or an organic film from a previous drink to me.

    parent root
    3 points Yamatocanyon

    I see it all the time when I use a French press. You get more oil from the beans in the coffee that way.

    parent root
    37 points ismailoverlan

    Oils. I worked as a waiter for 5 years and those bubbles are always soap or petroleum like.

    Caffeine is hell of a drug. Corporations implemented coffee breaks. They noticed those who drink coffee in the middle of the day would work better, produce more stuff, easily cover the coffee's expenses.

    50 years in. Now coffee breaks are in every field of production material and immaterial. Production is to the Moon yet we have to work like our grandparents for less pay. Life of a peasant sucks in any age.

    parent root
    4 points FeetPicsNull

    Long flight air force fighters used to get amphetamines until apparently caffeine proved to be good enough.

    parent root
    1 points Rooilia

    B 2 guys are still full of amphetamines when flying 48 hours straight.

    parent root
    1 points rubermnkey

    modafinil and it's analogs are popular too, no jitters and less amped up feeling.

    parent root
    3 points Rooilia

    Idk what effects these have nowadays, are they "safe" when the intake "can" be controlled?

    parent root
    1 points rubermnkey

    pretty safe, they stock them on the space station and you'll see doctors and other long shift workers besides military using it. there isn't really a high you just feel regular awake, caffeine is a stronger stimulant.

    parent root
    1 points Outrageous_Word_999

    They're all still on it bruh.

    parent root
    1 points ExternalScholar3472

    In UK we've always had tea breaks. Unions had to fight to get authorised breaks for the workers as well as fair pay and health and safety laws. Factory unions have had most of their powers taken away thats why they now have to work for peanuts.

    parent root
    6 points Any_Suggestion3485

    It’s a physics phenomenon called thin film interference. And is the same reason soap bubbles have a rainbow color! “The same but different.”

    parent root
    7 points scorpyo72

    Oils from coffee = the iridescence of the bubbles. Blowing on the bubbles redistributes the oils.

    parent root
    7 points Exciting_Ad_8666

    Oil? This coffee needs some good old fashioned American freedom

    parent root
    2 points ShimoFox

    Definitely the oils from the beans.

    parent root
    1 points thecementmixer

    Motor oil

    parent root
    1 points ItzyMidzyLocoStyle

    My fav 🤤🤤🤤

    parent root
    1 points mmazing

    chemicals from aliens

    parent root
    1 points AntSuccessful9147

    Nah, they got rainbow breath

    parent root
    1 points blazze_eternal

    The oils actually hold a lot of caffeine, and flavor. It's why I don't use paper filters, because those absorb all the oil.

    parent root
  • 134 points Oscar_Whispers

    Congratulations, your latent mutant powers have activated! Wolverine will be crashing through your living room wall shortly.

    parent
    15 points KobayashiWaifu

    OHHHH YEAHHH BUB

    parent root
    11 points dicemanshock

    Make sure you enjoy that beer....

    parent root
  • 46 points gorebello

    I think I actually know this one. I've seen a video about this in the past.

    Since the bubble is curved it is constantly filtering what is the wavelength it diffracts, so it may have many colors. There is also a constructive and destructive interpherence here.

    Blowing will change the curvature and thin the film of liquid at the top of the bubble compared to the bottom.

    This would explain why it appears after blowing. But why are they appearing.... maybe it happens a lot and we don't notice or maybe you have some soap there

    parent
    5 points MrNosco

    It's not due to the curvature, but due to the thickness of the bubble. When transitioning from air to water on the outside of the bubble, some of the light is reflected. This happens again when transitioning from water to air inside of the bubble. Depending on the thickness of the bubble, different wavelengths of light will destructively interfere with themselves, reducing or outright filtering themselves.

    This process is very sensitive to the exact thickness of the bubble, so small variations in thickness along the surface causes different colors to get filtered.

    parent root
    1 points gorebello

    Yes. And I expect the blowing might make it thinner.

    But the curvature might also make some difference in this case because we don't see lights, then we see them. Being less curved might influence the angles that point to the camera.

    parent root
    1 points heff66

    My understanding (primitive as it is) is that surface tension between the inner and outer layer of the bubble creates refraction.

    Blowing on them is bending those surfaces and changing the refractive index, producing the color change.

    parent root
  • 10 points squad1alum

    May I offer you a breath mint?

    parent
  • 8 points Lamb_Sauce02

    Dam that's pretty af

    parent
  • 8 points AandM4ever

    Magic guys!

    parent
    6 points 131_Proof_Bud

    magnets.

    parent root
    2 points Weelki

    How do they work?

    parent root
    3 points No_Draw_9224

    Nobody knows

    parent root
    2 points whatsabutters

    The coffee is black so….

    parent root
  • 5 points ogcoolhands

    I have this issue with dishwashing pods. That leaves enough of a residue to where you can't physically see it and the cup looks empty. But as you can see the residual from the soap is rehydrated

    parent
    3 points BAG3LWOLF

    Got that coffee that REALLY makes ya run to the toilet lol

    parent root
  • 6 points Then_I_had_a_thought

    This phenomenon is known as thin film interference. It has to do with different indices of refraction of the liquid and air inside the bubble. It doesn’t necessarily mean there is soap in your coffee.

    https://en.wikipedia.org/wiki/Thin-film_interference

    parent
  • 3 points Blinddeafndumb

    Soap residue

    parent
  • 3 points itaniumonline

    Are you gay by chance? This could explain it

    parent
    2 points flip4420

    Rainblowing

    parent root
  • 2 points Traditional_Fee_1965

    Great, now enjoy Ur soapy coffee :D

    parent
  • 2 points markjsb

    You're gay. I support the LGBT community!

    parent
  • 2 points tannercolin

    Everyone gets a superpower

    This is yours

    parent
  • 1 points cryptograndfather

    Superman is invulnerable and shoots lasers from his eyes.
    Professor Xavier is the most powerful telepath on Earth, he can read minds and manipulate the consciousness of others.
    Dude — makes bubbles in his mug multicolored. You're sweetheart Disney princess. =)

    parent
  • 1 points mchp92

    Woke coffee?

    parent
  • 1 points Dioz_31337

    Rainblow

    parent
  • 1 points ZookeepergameOk6784

    Gaaaaaayyy

    parent
  • 1 points wateraspect

    Bro is render enhancer in his breath

    parent
  • 1 points KoalifiedGorilla

    Very psychedelic lol

    parent
  • 1 points BikeAlpaca71

    I notice the same thing on my coffee 🙂 and it's not soap residue, used only plain hot water on mug

    parent
  • 1 points ClydePrefontaine

    Yep, bubbles are neat

    parent
  • 1 points FishermanExtreme6542

    Witchcraft.

    parent
  • 1 points Mathemus

    So it’s you who controls the bifrost?!

    parent
  • 1 points TheOnlyGuyver

    Light refraction. Nice.

    parent
  • 1 points hippodribble

    thin-film interference?

    parent
  • 1 points cuyeyo

    this is how happiness looks like for coffee lovers))) i get so much pleasure from this video

    parent
  • 1 points rydan

    Newton rolling in his grave

    parent
  • 1 points yobboman

    Did you put dishwashing liquid in your coffee?

    parent
  • 1 points tuvok86

    must be uk

    parent
  • 1 points lykosen11

    For sure oils from the coffee beans refracting light. Looks cool!

    parent
  • 1 points IdleRhymer

    This is how you know it isn't decaf.

    parent
  • 1 points Substantial_Bus6615

    You must be a unicorn!

    parent
  • 1 points Alternative_Pilot_92

    Soap.

    parent
  • 1 points Littlepastaboy

    If you blow really hard they will turn you into a rainbow

    parent
  • 1 points KedaiNasi_

    kinda drives me crazy every morning when i see it, but then it's natural.. thank god

    parent
  • 1 points Exact_Touch_4794

    You’ve got detergent residue in your coffee pot, not magic at all

    parent
  • 1 points Dpow3SUMXpow2

    brush your teeth

    parent
  • 1 points ziostraccette

    1.8k updoots on a post that has absolutely nothing to do with the sub

    parent
  • 1 points Blunt4words20

    I feel like a chemical engineer after reading this post

    parent
  • 0 points Lafawny

    Caferius Phonum

    Also known as the "Bad Breath Bean" Is a specific type of coffee bean that when grounded and exhaled upon can react in color depending on the odor in one's breath. Another important note is that i made this up completely

    parent
  • 0 points ConspiracyParadox

    When I was a kid I used to blow bubbles...

    I miss that clown.

    parent
  • 0 points Rostrow416

    When you blow, just say “no homo” and the rainbow bubbles should be gone

    parent
  • 0 points D-Train0000

    Just oil from the beans. when I make a strong cup of French you a see it in the surface at an angle.

    parent
  • 0 points MnstrPoppa

    Coffee has natural oils, oils get shiny-like sometimes. Bubbles made with oil-stained water gonna get shiny-like, too.

    parent
  • 0 points joeybaby106

    People keep talking about curvature here but I think it's actually about the thickness of a bubble when it becomes the same order of magnitude as the wavelength of light then you get these cool, constructive and destructive interference interactions. Potentially before you blew on it, the bubbles were too thick to have that interaction, which is why when you blow on it, it thins out and happens

    parent
  • 0 points schavi

    r/stevemould

    parent
  • 0 points biradinte

    You're a fairy

    parent
  • 0 points kking254

    The colors are created by thin film interference. The color produced depends on the thickness of the bubble walls. Maybe somehow blowing in the coffee changes this thickness (maybe blowing makes them thinner and then cohesive forces draw up liquid again and thicken them)?

    Changing the refractive index can also do it, like if blowing pushes away oil and leaves water behind, or vice versa.

    The effect of thin film interference is to "cancel" a narrow band of light. This tends to produce the colors cyan (red removed), yellow (blue removed), and magenta (green removed).

    parent
  • 0 points heynonnynonnomous

    That's not magic, that's oil.

    parent
  • 0 points Batfinklestein

    Who needs creme when you can have detergent am I right? 🫧

    parent
  • 0 points Okie294life

    Coffe has oil in it, oil creates a rainbow effect when suspended on top of water…not too difficult to figure out.

    parent
  • 0 points Fairdinkum16

    Ahhh Americans…

    parent
  • 0 points WhileNo1095

    Esa mierda toda mal lavada jajaja y se asombra el cochino

    parent
  • -1 points MissChonkyWonky

    Rinse ya fkn dishes better lol

    parent
  • -1 points ReasonableGas8904

    Dude, you’ve got way too much time on your hands…

    parent
  • -2 points Heavy-Commercial-323

    Don’t drink it, it could be soap or some coating from your pot malfunctioning

    parent
  • -5 points PiratesTale

    We hate to tell you that you’re not special, so we won’t.

    parent
  • Hacker News
    • Top
    • Best
    • New
    • Ask
    • Show
    • Jobs
  • beta Hugging Face
    • Posts
  • Reddit
    • r/programming
    • r/technology
    • r/science
    • r/news
    • r/gaming