Astronaut propulsion unit Astronaut propulsion unit An astronaut propulsion unit (or astronaut maneuvering unit) is used to move an astronaut relative to the spaceship during a spacewalk. The first astronaut propulsion unit was the Hand-Held Maneuvering Unit (HHMU) used on Gemini 4. The Hand-Held Maneuvering Unit was the EVA "zip" gun used by Ed White on the Gemini 4 mission in 1965. The hand-held gun held several pounds of nitrogen, and allowed limited movement around the Gemini spacecraft. It was also used by astronaut Michael Collins on the Gemini 10 mission in 1966. The United States Air Force (USAF) Astronaut Maneuvering Unit (AMU)
Chinese as a foreign language in 2001, while the later has not been found so far—Ricci made the transcription system developed in 1598, and in 1626 it was finally published, with minor modifications, by another Jesuit Nicolas Trigault in a guide for new Jesuit missionaries. The system continued to be in wide use throughout the 17th and 18th century. It can be seen in several Romanized Chinese texts (prepared mostly by Michael Boym and his Chinese collaborators) that appeared in Athanasius Kircher's "China Illustrata". The earliest Chinese grammars were produced by the Spanish Dominican missionaries. The earliest surviving one is by Francisco Varo (1627–1687). His