Memoir, autobiography, biography. A memoir is a special kind of autobiography, usually involving a public portion of the authorâs life as it relates to a person, historic event, or thing. The text is about the personal knowledge and/or experiences of the author. literary agent discusses the contents of a quality memoir and how it differs from an autobiography or biography. Memoirs are perennially popular with many new books coming out each year. The bestseller, Night, by Elie Wiesel, is a memoir, not an autobiography or biography.
According to CelesTrak there are 2,691 inactive satellites in orbit. 1,490 satellites are active for a total of 4,181. [1] The UCS Satellite Database has an equivalent number. [2]
A GPS receiver must be locked on to the signal of at least 3 satellites to calculate a 2-D position (latitude and longitude) and track movement. With four or more satellites in view, the receiver can determine the user's 3-D position (latitude, longitude and altitude). The first GPS satellite was launched in 1978. 2  A full constellation of 24 satellites was achieved in 1994. 3  Each satellite is built to last about 10 years. 4  Replacements are constantly being built and launched into orbit.