Geostamping is an active area of research in the Cardano community. In the last year, Cardano Foundation released a report detailing how a geostamp (combination of a timestamp and a geolocation) could be created for the blockchain using the open source GeoGnomo project. The three geocoding techniques implemented by GeoGnomo include: QTS (Quarternary Triangular System), QRS (Quarternary Rectangular System) and VRS (Variable Rectangular System.) These algorithms work by dividing the earth into self-similar rectangles or triangles and giving each shape a unique label. Compared to the traditional approach of geocoding by latitude/longitude, these systems come with the benefit of a compact, human-readable representation, but at the cost of precision. The space-filling shapes used by GeoGnomo are not very precise because each algorithm uses only one type of shape, i.e. a triangle or a rectangle. Higher levels of resolution can be achieved by using Hilbert curves, a fractal shape that can fill a geometric space more densely. An additional benefit of encoding with Hilbert curves is that it allows for integration with geospatial search and indexing tools built by Google.
I propose researching a way of representing Hilbert curves on the blockchain using GeoGnomo. The challenges of this project include implementing a bridge between GeoGnomo and S2, and coming up with compact and human readable representations for S2 hashes.