FCC IAS #2 - Bonfire: Map the Debris

function orbitalPeriod(arr) {
  var GM = 398600.4418;
  var earthRadius = 6367.4447;
  var newArr = [];
  
  arr.forEach(function(body) {
    var a = earthRadius + body.avgAlt;
    var t = Math.round(2*(Math.PI)*Math.sqrt(Math.pow(a, 3)/GM));
    newArr.push({name:body.name, orbitalPeriod:t})
  })

  return newArr;
}

orbitalPeriod([{name : "sputkin", avgAlt : 35873.5553}]);