Convert from gigaparsec to stride [great]

Unit Definition (gigaparsec)
The Gigaparsec is a non-metric unit of distance equal to one billion parsecs, 3.2616 billion light years, or 30.856 78 zettameters (30.856 78 x 1021 kilometers). The unit is used in astronomy.

Unit Definition (stride [great])
Distance between consecutive prints of the same foot in a track, measured from the same point on each foot.