R. Angeloni, F. Di Mille, J. Bland-Hawthorn, D. Osip, -
Highly-collimated gas ejections are among the most dramatic structures in the
Universe, observed to emerge from very different astrophysical systems - from
active galactic nuclei down to young brown dwarf stars. Even with the huge span
in spatial scales, there is convincing evidence that the physics at the origin
of the phenomenon, namely the acceleration and collimation mechanisms, is the
same in all classes of jets. Here we report on the discovery of a giant,
highly-collimated jet from Sanduleak's star in the Large Magellanic Cloud
(LMC). With a physical extent of 14 parsecs at the distance of the LMC, it
represents the largest stellar jet ever discovered, and the first resolved
stellar jet beyond the Milky Way. The kinematics and extreme chemical
composition of the ejecta from Sanduleak's star bear strong resemblance with
the low-velocity remnants of SN1987A and with the outer filaments of the most
famous supernova progenitor candidate, i.e., eta Carinae. Moreover, the precise
knowledge of the jet's distance implies that it will be possible to derive
accurate estimates of most of its physical properties. Sanduleak's bipolar
outflow will thus become a crucial test-bed for future theoretical modeling of
astrophysical jets.
View original:
http://arxiv.org/abs/1111.0848
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