|A&A Press Release: A jet of molecular hydrogen arising from a forming high-mass star (7 March 2007)|
A&A press release
Released on March 7th, 2007
“Formation of a massive protostar through disk accretion. II. SINFONI integral field spectroscopy of the M17 silhouette disk and discovery of the associated H2 jet ”, by Nürnberger et al.
A team of European astronomers offer new evidence that high-mass stars could form in a similar way to low-mass stars, that is, from accretion of gas and dust through a disk surrounding the forming star. Their article, published in Astronomy & Astrophysics, reports the discovery of a jet of molecular hydrogen arising from a forming high-mass star located in the Omega nebula (M17). This detection confirms the hypothesis based on their earlier discovery that this forming high-mass star is surrounded by a large accretion disk.
Fig. 1 - Left: Near-infrared image of the M17 silhouette disk, discovered in 2004. The field of view is 27"x27", which roughly corresponds to 60000 AU x 60000 AU (AU stands for astronomical units). Right: Zoom on the central region at six selected wavelengths. The pictures were obtained with SINFONI. Each panel has a field of view of 4.8"x3.6" (i.e. 10560 AU x 7920 AU). While panels (b), (d), and (f) show the densest inner part of the silhouette disk, panels (c) and (e) reveal the H2 jet (individual emission knots are labelled with A, B, and C).
A high-mass star is a star of more than 8 times the solar mass.
 For information about this earlier discovery, see the ESO press release and the article published in the ESO Messenger.
 SINFONI (for "Spectrograph for INtegral Field Observation in the Near-Infrared") is one of the most recent instruments installed at the ESO-VLT. Associated to an adaptive optics module, it provides very high-angular resolution spectra and images. Technical details and first results can be found on the ESO web site.
 The team includes D.E.A. Nürnberger (ESO), R. Chini (Ruhr-Universität Bochum, Germany), F. Eisenhauer (MPE, Garching, Germany), M. Kissler-Patig, A. Modigliani, R. Siebenmorgen, M.F. Sterzik, T. Szeifert (ESO).
Formation of a massive protostar through disk accretion. II. SINFONI integral field spectroscopy of the M17 silhouette disk and discovery of the associated H2 jet
© Astronomy & Astrophysics 2007