let a=2;
let x=2;
let y=7;
let r=80;
function setup() {
createCanvas(500,500);
colorMode(HSB,360,100,50);
//background(120);
}
function draw(){
a+=2;
noStroke();
fill(random(166),170,150);
r=random(150,50);
y=r*sin(radians(a))+250;
x=r*cos(radians(a))+250;
ellipse(x,y,50,50);
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/1.1.9/p5.min.js"></script>