anchor.diff:  
           //
   
  -        await this.updateSessions();
  +        this.updateSessions();
           this.setURL();
   
           ObservatorySession nearest = this.findDetailSession();
  
positive.code:         }
      }
  
      Future<Null> goToCoordinates(num x, num y) async {
          x = x.floor();
          y = y.floor();
  
  
negative.code: 
      ObservatorySession(ObservatoryViewer this.parent, int this.seed, int this.x, int this.y) {
          this.rand = new Random(seed);
  
          this.session = parent.getSession(seed);
  
          this.initial_rotation = rand.nextDouble(Math.PI * 2);
          this.rotation_speed = rand.nextDouble() * (max_rotation - min_rotation) + min_rotation;
  