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Recent analysis of the decay products of short-lived radiounclides (SLRs) in meteorites, in particular the confirmation of the presence of live 60Fe in the early Solar System, provides unambiguous evidence that the Sun and Solar System formed near a massive star. We consider the question of the formation of low-mass stars in environments near massive stars, presenting a scenario for the evolution of a star and its disk around the periphery of an expanding H II region. The stages in this scenario begin with compression of molecular gas around the edge of an H II region, continue as forming stars are overrun by the advancing ionization front, and culminate when ejecta from one or more nearby supernova explosions sweeps over YSO disks located in the low density interior of the H II region, injecting SLRs including 26Al and 60Fe. We review the evidence that this mode of star formation is more characteristic of formation of low-mass stars than is the mode of star formation seen in regions such as the Taurus-Auriga molecular cloud. We discuss the implications of this scenario for our understanding of star formation, as well as the effects of the young Suns astrophysical environment on the formation and evolution of the Solar System. We conclude that low-mass stars and their accompanying disks form and evolve very differently near massive stars than they do in regions like Taurus-Auriga, and that these differences have profound implications for our understanding of our origins.
The formation and properties of star clusters formed at the edges of H II regions are poorly known. We study stellar content, physical conditions, and star formation processes around a relatively unknown young H II region IRAS 10427-6032, located in
GLIMPSE imaging using the Infrared Array Camera (IRAC) on the Spitzer Space Telescope indicates that star formation is ongoing in the RCW 49 giant H II region. A photometric comparison of the sources in RCW 49 to a similar area to its north finds tha
We report the observational findings of the Sh2-112 H{sc ii} region by using the multiwavelength data analysis ranging from optical to radio wavelengths. This region is powered by a massive O8V-type star BD +45 3216. The surface density distribution
We performed a multiwavelength study towards HII region Sh2-104. New maps of 12CO J=1-0 and 13CO J=1-0 were obtained from the Purple Mountain Observatory (PMO) 13.7 m radio telescope. Sh2-104 displays a double-ring structure. The outer ring with a ra
We describe studies of star formation in various galaxies using primarily observations from the Wise Observatory. In addition to surface photometry in the broad band UBVRI, we also use a set of narrow-band H-alpha filters tuned to different redshifts