NASA Astronaut Corps their home agency but trained with and serve alongside their NASA counterparts. International astronauts, Payload Specialists, and Spaceflight Participants are not considered members of the NASA Astronaut Corps. The term "Astronaut Candidate" (informally "ASCAN") refers to individuals who have been selected by NASA as candidates for the NASA Astronaut Corps and are currently undergoing a candidacy training program at the Johnson Space Center. The most recent class of Astronaut Candidates was selected in 2017 after receiving more than 18,300 applications. Upon completion of a two-year training program, they will be promoted to the rank of Astronaut. Selection as an Astronaut
Chinese as a foreign language Chinese as a foreign language Chinese as a foreign or second language is the study of the Chinese varieties by non-native speakers. Increased interest in China from those outside has led to a corresponding interest in the study of Standard Chinese ("Mandarin") as a foreign language, the official language of mainland China and Taiwan. However, the teaching of Chinese both within and outside China is not a recent phenomenon. Westerners began learning different Chinese varieties in the 16th century. Within China, Mandarin became the official language in the early 20th century. Mandarin also became the official language of Taiwan when