20th Anniversary of Hong Kong Special Autonomous Region (Hong Kong 2017)

Stamp 20th Anniversary of Hong Kong Special Autonomous Region it reflects the thematic directions:

A hot air balloon is a lighter-than-air aircraft consisting of a bag, called an envelope, which contains heated air. Suspended beneath is a gondola or wicker basket (in some long-distance or high-altitude balloons, a capsule), which carries passengers and a source of heat, in most cases an open flame caused by burning liquid propane. The heated air inside the envelope makes it buoyant, since it has a lower density than the colder air outside the envelope. As with all aircraft, hot air balloons cannot fly beyond the atmosphere. The envelope does not have to be sealed at the bottom, since the air inside the envelope is at about the same pressure as the surrounding air. In modern sport balloons the envelope is generally made from nylon fabric, and the inlet of the balloon (closest to the burner flame) is made from a fire-resistant material such as Nomex. Modern balloons have been made in many shapes, such as rocket ships and the shapes of various commercial products, though the traditional shape is used for most non-commercial and many commercial applications.

The hot air balloon is the first successful human-carrying flight technology. The first untethered manned hot air balloon flight in the world was performed in Paris, France, by Jean-François Pilâtre de Rozier and François Laurent d'Arlandes on November 21, 1783, in a balloon created by the Montgolfier brothers. The first hot air balloon flown in the Americas was launched from the Walnut Street Jail in Philadelphia on January 9, 1793, by the French aeronaut Jean Pierre Blanchard. Hot air balloons that can be propelled through the air rather than simply drifting with the wind are known as thermal airships.

Family (from Latin: familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). It forms the basis for social order. The purpose of the family is to maintain the well-being of its members and of society.[according to whom?] Ideally, families offer predictability, structure, and safety as members mature and learn to participate in the community. Historically, most human societies use family as the primary purpose of attachment, nurturance, and socialization

A park is an area of natural, semi-natural or planted space set aside for human enjoyment and recreation or for the protection of wildlife or natural habitats. Urban parks are green spaces set aside for recreation inside towns and cities. National parks and country parks are green spaces used for recreation in the countryside. State parks and provincial parks are administered by sub-national government states and agencies. Parks may consist of grassy areas, rocks, soil and trees, but may also contain buildings and other artifacts such as monuments, fountains or playground structures. Many parks have fields for playing sports such as baseball and football, and paved areas for games such as basketball. Many parks have trails for walking, biking and other activities. Some parks are built adjacent to bodies of water or watercourses and may comprise a beach or boat dock area. Urban parks often have benches for sitting and may contain picnic tables and barbecue grills.