text: var SGP4 = require('sgp4');
  
  // Sample ISS TLE Data from March 26, 2016
  var issLine1 = "1 25544U 98067A   16092.70325827  .00016717  00000-0  10270-3 0  9043";
  var issLine2 = "2 25544  51.6422  79.5083 0002610  15.3326 344.7906 15.54337099 33086";
  
  //
  // ISS
  //     1 25544U 98067A   16092.70325827  .00016717  00000-0  10270-3 0  9043
  //     2 25544  51.6422  79.5083 0002610  15.3326 344.7906 15.54337099 33086
  // Time: Fri Apr 01 7:47 PM, Visible: 4 min, Max Height: 49°, Appears: 38° above W, Disappears: 12° above NE
  
  console.log(' ')
      // Create a satellite record
  var issSatRec = SGP4.twoline2rv(issLine1, issLine2, SGP4.wgs84());
  // console.log('SPG4.wgs84()', SGP4.wgs84());
  //  console.log('issSatRec', issSatRec);
  
  // This will print some info every 3/4th second
  function printPosition() {
      // Current time
  
      // var now = new Date();
      var tsec = 20
      var now = new Date(2016, 3, 1, 16, 52, tsec);
      console.log('cdate:  ', now);
  
      //  3/27/2016  12:44:29 PM
  
      var spotdate = new Date(2016, 2, 29, 20, 44, 29);
      console.log('spotdate:  ', spotdate);
  
      // This will contain ECI (http://en.wikipedia.org/wiki/Earth-centered_inertial) coordinates of position and velocity of the satellite
      var positionAndVelocity = SGP4.propogate(issSatRec, now.getUTCFullYear(), now.getUTCMonth() + 1, now.getUTCDate(), now.getUTCHours(), now.getUTCMinutes(), now.getUTCSeconds());
  
      // Prints ECI coordinates
      console.log(positionAndVelocity);
  
      // GMST required to get Lat/Long
      var gmst = SGP4.gstimeFromDate(now.getUTCFullYear(), now.getUTCMonth() + 1, now.getUTCDate(), now.getUTCHours(), now.getUTCMinutes(), now.getUTCSeconds());
  
      // Geodetic coordinates
      var geodeticCoordinates = SGP4.eciToGeodetic(positionAndVelocity.position, gmst);
  
      // Coordinates in degrees
      var longitude = SGP4.degreesLong(geodeticCoordinates.longitude);
      var latitude = SGP4.degreesLat(geodeticCoordinates.latitude);
  
      // Prints latitude of longitude of ISS
      console.log('Lat/Long: ' + latitude + ' ' + longitude);
  
      // Prints current speed of satellite in km/s
      // console.log('Velocity: ' + geodeticCoordinates.velocity + ' km/s');
  
      // Prints orbital period of satellite in minutes
      // 2pi * sqrt(Relative Height / Gravity of Earth * Mass of Earth)
      console.log('Oribital Period: ' + ((2 * Math.PI) * (geodeticCoordinates.height + 6378.135)) * (Math.sqrt((geodeticCoordinates.height + 6378.135) / 398600.8)) / 60);
  
      var observerPos = {
          // longitude: -117.61199249999999 * SGP4.deg2rad,
          // latitude: 33.4269728 * SGP4.deg2rad,
          longitude: -86.52 * SGP4.deg2rad,
          latitude: 34.728 * SGP4.deg2rad,
          height: 1
      };
  
      var satEcf = SGP4.eciToEcf(positionAndVelocity.position, gmst);
      var lookAngles = SGP4.topocentricToLookAngles(SGP4.topocentric(observerPos, satEcf));
  
      // console.log("Azimuth: " + lookAngles.azimuth * SGP4.rad2deg);
      // console.log("Elevation: " + lookAngles.elevation * SGP4.rad2deg);
  
      // Call printPosition in 750 ms
      // setTimeout(printPosition, 750);
  }
  printPosition();
  