code: func (p *Point) BearingTo(point *Point) float64 {
  	dLng := deg2rad(point.Lng() - p.Lng())
  
  	pLatRad := deg2rad(p.Lat())
  	pointLatRad := deg2rad(point.Lat())
  
  	y := math.Sin(dLng) * math.Cos(pointLatRad)
  	x := math.Cos(pLatRad)*math.Sin(pointLatRad) - math.Sin(pLatRad)*math.Cos(pointLatRad)*math.Cos(dLng)
  
  	return rad2deg(math.Atan2(y, x))
  }
docs: // BearingTo computes the direction one must start traveling on earth
  // to be heading to the given point.