- A Hipparcos Census of the Nearby OB Associations (iopscience.iop.org)
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.
- The Origin of Consciousness in the Breakdown of the Bicameral Mind (Wikipedia)
The Origin of Consciousness in the Breakdown of the Bicameral Mind is a 1976 book by the Princeton psychologist, psychohistorian and consciousness theorist Julian Jaynes (1920-1997). The book addresses the problematic nature of consciousness – “the ability to introspect” – which in Jaynes’ view must be distinguished from sensory awareness and other processes of cognition. Jaynes presents his proposed solution: that consciousness is a learned behavior based more on language and culture than on biology; this solution, in turn, points to the origin of consciousness in ancient human history rather than in metaphysical or evolutionary processes; furthermore, archaeological and historical evidence indicates that prior to the learning of consciousness, human mentality was what Jaynes called “the bicameral mind” – a mentality based on verbal hallucination.
- OB association (Wikipedia)
Young associations will contain 10 to 100 massive stars of spectral class O and B, and are known as OB associations. In addition, these associations also contain hundreds or thousands of low- and intermediate-mass stars. Association members are believed to form within the same small volume inside a giant molecular cloud. Once the surrounding dust and gas is blown away, the remaining stars become unbound and begin to drift apart.