switch(true) {
case (planet.toUpperCase() === "SUN"):
  text2 = "hero";
  break;
case (planet.toUpperCase() === "MOON"):
  text2 = "mother";
  break;
case (planet.toUpperCase() === "MERCURY"):
  text2 = "twin";
  break;
case (planet.toUpperCase() === "Venus"):
  text2 = "courtesan";
  break;
case (planet.toUpperCase() === "MARS"):
  text2 = "soldier";
  break;
default:
  text2 = "planet";
}

if(planet === "sun" || planet === "Sun" || planet === "SUn") {
  // text assignment
}

if (planet.toLowerCase() === "sun") {
  // text assignment
}