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two stars that appear as one if not viewed through a telescope with adequate magnification, such as two stars that are separated by a great distance but are nearly in line with each other and an observer (optical double star) or those that are relatively close together and comprise a single physical system (physical double star)
two stars, appearing close together when viewed through a telescope; either physically associated (binary star) or not associated (optical double star) See also binary star, optical double star
See binary star.
noun 1. systematic instruction in sports, exercises, and hygiene given as part of a school or college program. noun 1. training and practice in sports, gymnastics, etc, as in schools and colleges PE physical education n. Abbr. phys. ed., phys ed Education in the care and development of the human body, stressing athletics and including […]
noun 1. an examination, usually by a physician, of a person’s body in order to determine his or her state of health or physical fitness, as for military service or participation in a sport. noun 1. (med) the process of examining the body by means of sight, touch, percussion, or auscultation to diagnose disease or […]
- Physical file
file system A low-level view of the physical characteristics of a file, such as its location on a disk or its physical structure, for example, whether indexed or sequential. (2004-12-23)
noun 1. the branch of geography concerned with natural features and phenomena of the earth’s surface, as landforms, drainage features, climates, soils, and vegetation. noun 1. the branch of geography that deals with the natural features of the earth’s surface physical geography The scientific study of the natural features of the Earth’s surface, especially in […]