19 Aquarii 19 Aquarii 19 Aquarii is a star in the constellation of Aquarius. With an apparent magnitude of about 5.7, the star is barely visible to the naked eye (see Bortle scale). Parallax estimates made by the Hipparcos spacecraft put it at a distance of about 300 light years (92 parsecs) away from the Earth. 19 Aquarii has a spectral type of A8V, meaning it is an A-type main-sequence star. These types of stars are bluish-white colored, and have effective temperatures between 7100 and 11500 K. It rotates fairly fast, as its projected rotational velocity is about 155 km/s, so it
History of measurement systems in Pakistan of Pakistan adopted the International System of Units (SI) Kos is an ancient unit of distance used in South Asia which is about 2.25 miles. Kos may also refer to about 1.8 km (1⅛ mile) or 3.2 km (2 miles). The Mughal Empire used Farsang (Parsang) for distance, which was in principle the distance a horse would walk in an hour, about 3 miles = 12,000 cubits. A Kanal is a unit of area, equivalent to 5445 square feet or one-eighth of an acre. It is mainly used in Punjab province of Pakistan. Under British rule the Marla and Kanal