how do you animate many ellipses that were made at random?

How do you make a moving background a randomly placed ellipses to repeat forever from left to right.

background(29, 40, 115);

for (var i = 1; i < 400; i +=1) {
var blueValue = random(74,168);
var x = random(-400,400);
var y = random(-400,400);
var h = random(3,5);
var w = h;
noStroke();
fill(255, 255, blueValue);
ellipse(x, y, h, w);   
}



  draw = function() {
 //want to make stars move here?
  };