Why & How do I see this heart-shaped cardioid formed in my cup

Ok, first of all if you don’t know what I’m talking about, I’m talking about this shape in a cup of tea/coffee (or even water). I first got curious about this weird shape appearing in my cup a few…

calculus - Cardioid in a coffee cup - Mathematics Stack Exchange

I Heart Cardioids – David Richeson: Division by Zero

What is the equation that gives you a heart on the graph? - Quora

Cardioid

I Heart Cardioids – David Richeson: Division by Zero

All stories published by The Startup on February 06, 2020 – Medium

A Heart-Shaped History

Optics: Why does a heart shape sometimes form in a coffee mug? - Quora

All stories published by The Startup on February 06, 2020 – Medium