alphabetizeArray.js

var moonWalkers = [
  "Neil Armstrong",
  "Buzz Aldrin",
  "Pete Conrad",
  "Alan Bean",
  "Alan Shepard",
  "Edgar Mitchell",
  "David Scott",
  "James Irwin",
  "John Young",
  "Charles Duke",
  "Eugene Cernan",
  "Harrison Schmitt"
];

function alphabetizeArray(names) {
  var namesAlpha = [];
  for (var name in names){
    var splitArray = names[name].split(" ");
    var fname = splitArray[0];
    var lname = splitArray[1];
    var nameReversed = lname.concat(" ", fname);
    namesAlpha.push(nameReversed);
    namesAlpha.sort();
  }
  return namesAlpha;
}

console.log(alphabetizeArray(moonWalkers));