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arXiv · astro-ph/0305502

Discovery of a dust cloud next to sigma Orionis

Jacco Th. van Loon·Joana M. Oliveira
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Abstract

We report on the discovery of a mid-infrared source at a projected distance of only 1200 AU from the O9.5 V star sigma Orionis. The spatially resolved, fan-shaped morphology and the presence of an ionization front, as well as evidence in the spectrum for processed dust grains, all suggest that it is a proto-planetary disk being dispersed by the intense ultraviolet radiation from sigma Orionis. We compute the mass budget and the photo-evaporation timescale, and discuss the possible nature of this remarkable object.

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Jacco Th. van Loon, Joana M. Oliveira. 2003-05-27. Discovery of a dust cloud next to sigma Orionis. https://doi.org/10.1051/0004-6361%3A20030811

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