7 research outputs found
Waves on the surface of the Orion molecular cloud
Massive stars influence their parental molecular cloud, and it has long been
suspected that the development of hydrodynamical instabilities can compress or
fragment the cloud. Identifying such instabilities has proved difficult. It has
been suggested that elongated structures (such as the `pillars of creation')
and other shapes arise because of instabilities, but alternative explanations
are available. One key signature of an instability is a wave-like structure in
the gas, which has hitherto not been seen. Here we report the presence of
`waves' at the surface of the Orion molecular cloud near where massive stars
are forming. The waves seem to be a Kelvin-Helmholtz instability that arises
during the expansion of the nebula as gas heated and ionized by massive stars
is blown over pre-existing molecular gas.Comment: Preprint of publication in Natur
Laboratory Studies of Astrophysical Jets
Jets and outflows produced during star-formation are observed on many scales:
from the "micro-jets" extending a few hundred Astronomical Units to the
"super-jets" propagating to parsecs distances. Recently, a new "class" of
short-lived (hundreds of nano-seconds) centimetre-long jets has emerged in the
laboratory as a complementary tool to study these complex astrophysical flows.
Here I will discuss and review the recent work done on "simulating"
protostellar jets in the laboratory using z-pinch machines.Comment: 25 Pages, 11 Figures to appear in Lecture Notes in Physics. Series
Title: Jets from young stars IV: From models to observations and experiments
Editors: P. J. V. Garcia and J. M. T. Ferreira. Publisher: Springe