a binary star that can be recognized as such because of its undulating proper motion.
See under binary star.
. . . astronomer astronomical astronomy
a person engaged in or trained for spaceflight. Contemporary Examples There will be the first doctor, whoever does it.The first astronaut, whoever does it. Jerry Springer Wants His Privacy Lloyd Grove April 17, 2010 “If I had said I wanted to be an astronaut, they would have been like ‘Do it’,” Rivers told me. Joan […]
of or relating to or .
- Astronautical engineering
See under . the branch of engineering that deals with the design, development, testing, and production of aircraft and related systems (aeronautical engineering) and of spacecraft, missiles, rocket-propulsion systems, and other equipment operating beyond the earth’s atmosphere (astronautical engineering)
noun a navigational instrument for giving directional bearings from the centre of the earth to a particular star. It is carried in long-range aircraft, ships, spacecraft, etc