~~That’s probably Coriolis effect – you are seeing the earth’s rotation.~~
I read too much Expanse and not enough Physics Textbook.
Sebashtiantv on
I mean I tend to spiral without any discernable reason as well
Your ink needles may need therapy
BluetheNerd on
Convection currents! Heating and cooling of the water causes the water to swirl. It’s subtle enough you wouldn’t be able to feel it if you put a finger in the water, but the ink can be carried by it.
AaronFire on
Who’s all waiting for that really smart person to come in with the two paragraph answer that none of us understand?
squeezy102 on
The needles were at room temperature when you put them in, or slightly above because you touched them and well, body heat.
The water was cooler, and convection is creating a current of rising warm water.
Neat!
Schnapper94 on
lowkey looks like a portal opening up
GenericUsername2056 on
This is a result of the Marangoni effect. The surface tension of ink and water differ, and the gradient between them causes a driving force. The water, having a higher surface tension, is pulling on the ink, which causes it to move.Â
howmanyowlsisweird on
Me too, ink. Me too
ptv83 on
Could be caused by many things, without knowing if the ink is a polar molecule then can’t really say exactly what is causing it, but very cool.
(Some interesting theories in the replies)
Saisei on
Not stationary though.
lwarB on
Man, i chose a bad time to read uzumaki
Null-34 on

Wake up.
TheMagicalSock on
r/fountainpens is leaking
Retrospektic on
Idk why my first thought was how that liquid looked like a refreshing af beverage.
SevenLegs_ on
When I was a kid and my moms coffee kept slowly spinning in the cup for no reason (that I could see / comprehend) I thought it was because the Earth spins but the liquid was staying in the same spot. This reminded me of that.
15 Comments
~~That’s probably Coriolis effect – you are seeing the earth’s rotation.~~
I read too much Expanse and not enough Physics Textbook.
I mean I tend to spiral without any discernable reason as well
Your ink needles may need therapy
Convection currents! Heating and cooling of the water causes the water to swirl. It’s subtle enough you wouldn’t be able to feel it if you put a finger in the water, but the ink can be carried by it.
Who’s all waiting for that really smart person to come in with the two paragraph answer that none of us understand?
The needles were at room temperature when you put them in, or slightly above because you touched them and well, body heat.
The water was cooler, and convection is creating a current of rising warm water.
Neat!
lowkey looks like a portal opening up
This is a result of the Marangoni effect. The surface tension of ink and water differ, and the gradient between them causes a driving force. The water, having a higher surface tension, is pulling on the ink, which causes it to move.Â
Me too, ink. Me too
Could be caused by many things, without knowing if the ink is a polar molecule then can’t really say exactly what is causing it, but very cool.
(Some interesting theories in the replies)
Not stationary though.
Man, i chose a bad time to read uzumaki

Wake up.
r/fountainpens is leaking
Idk why my first thought was how that liquid looked like a refreshing af beverage.
When I was a kid and my moms coffee kept slowly spinning in the cup for no reason (that I could see / comprehend) I thought it was because the Earth spins but the liquid was staying in the same spot. This reminded me of that.