- P. T. de Zeeuw
- R. Hoogerwerf
- J. H. J. de Bruijne
- A. G. A. Brown
- A. Blaauw
- A comprehensive census of the stellar content of the OB associations within 1 kpc from the Sun is presented, based on Hipparcos positions, proper motions, and parallaxes. It is a key part of a long-term project to study the formation, structure, and evolution of nearby young stellar groups and related star-forming regions. OB associations are unbound “moving groups,” which can be detected kinematically because of their small internal velocity dispersion. The nearby associations have a large extent on the sky, which traditionally has limited astrometric membership determination to bright stars (V ≲ 6 mag), with spectral types earlier than ∼B5. The Hipparcos measurements allow a major improvement in this situation.
first scientific paper of
- Uiua (uiua.org)
Uiua (wee-wuh) is a general purpose, stack-based, array-oriented programming language with a focus on simplicity, beauty, and tacit code. Uiua lets you write code that is as short as possible while remaining readable, so you can focus on problems rather than ceremony. The language is not yet stable, as its design space is still being explored. However, it is already quite powerful and fun to use!