imaging companies sell images by licensing them to governments and businesses such as Apple Maps and Google Maps. Satellite telecommunications Satellites can be used to transmit and receive Internet services from space to any place in the planet Earth. Satellite navigation A satellite navigation or satnav system is a system that uses satellites to provide autonomous geo-spatial positioning. It allows small electronic receivers to determine their location (longitude, latitude, and altitude/elevation) to high precision (within a few centimeters to metres) using time signals transmitted along a line of sight by radio from satellites. The system can be used for providing position, navigation or for tracking the position of something fitted with a receiver (satellite tracking). The signals also allow the electronic receiver to calculate the current local time to high precision, which allows time synchronisation. These uses are collectively known as Positioning, Navigation and Timing (PNT). Satnav systems operate independently of any telephonic or internet reception, though these technologies can enhance the usefulness of the positioning information generated. Space tourism Space tourism is human space travel for recreational purposes. There are several different types of space tourism, including orbital, suborbital and lunar space tourism. To date, orbital space tourism has been performed only by the Russian Space Agency. Work also continues towards developing suborbital space tourism vehicles. This is being done by aerospace companies like Blue Origin and Virgin Galactic. In addition, SpaceX (an aerospace manufacturer) announced in 2018 that they are planning on sending space tourists, including Yusaku Maezawa, on a free-return trajectory around the Moon on the Starship. Commercial recovery of space resources Commercial recovery of space resources is the exploitation of raw materials from asteroids, comets and other space objects, including near-Earth objects. Minerals and volatiles could be mined then used in space for in-situ utilization (e.g. construction materials and rocket propellant) or taken back to Earth. These include gold, iridium, silver, osmium, palladium, platinum, rhenium, rhodium, ruthenium and tungsten for transport back to Earth; iron, cobalt, manganese, molybdenum, nickel, aluminium, and titanium for construction; water and oxygen to sustain astronauts; as well as hydrogen, ammonia, and oxygen for use as rocket propellant. There are several commercial enterprises working in this field, including Planetary Resources and Deep Space Industries. Regulation Beyond the many technological factors that could make space commercialization more widespread, it has been suggested that the lack of private property, the difficulty or inability of