Related papers: Orion Outlying Clouds
The Orion-Eridanus superbubble has been blown by supernovae and supersonic winds of the massive stars in the Orion OB associations. The formation history and current structure of the superbubble are still poorly understood. It possibly…
We report the discovery of active star formation in Digel's Cloud 2, which is one of the most distant giant molecular clouds known in the extreme outer Galaxy (EOG). At the probable Galactic radius of ~20 kpc, Cloud 2 has a quite different…
Large scale far-infrared (FIR) observations of the Orion complex at 205 and 138 micron are presented with an aim of studying the distribution of cold (< 25 K) dust. The maps in these FIR bands extend over approximately 3600 sq. arcmin and…
The Oort cloud is usually thought of as a collection of icy comets inhabiting the outer reaches of the Solar system, but this picture is incomplete. We use simulations of the formation of the Oort cloud to show that ~4% of the small bodies…
The extreme outer Galaxy (EOG) has a very different environment from that in the solar neighborhood, with low metallicity (less than -0.5 dex), much lower gas density, and small or no perturbation from spiral arms. The EOG is an excellent…
We study stellar-halo formation using six Milky Way-mass galaxies in FIRE-2 cosmological zoom simulations. We find that $5-40\%$ of the outer ($50-300$ kpc) stellar halo in each system consists of $\textit{in-situ}$ stars that were born in…
Vibration-rotation lines of H$_{2}$ from highly excited levels approaching the dissociation limit have been detected at a number of locations in the shocked gas of the Orion Molecular Cloud (OMC-1), including in a Herbig-Haro object near…
We present a summary of main results from the studies performed in the series of papers "The chemical composition of the Orion star forming region". We reinvestigate the chemical composition of B-type stars in the Orion OB1 association by…
Diffuse far-UV emission arising from the edge of the Orion-Eridanus superbubble was observed with the SPEAR imaging spectrometer, revealing numerous emission lines arising from both atomic species and H2. Spatial variations in line…
Using the IRAM 30m telescope we have surveyed a $1\times0.8^{\circ}$ part of the Orion molecular cloud in the $^{12}$CO and $^{13}$CO (2-1) lines with a maximal spatial resolution of $\sim$11" and spectral resolution of $\sim$ 0.4…
Using CARMA, we imaged the 87 GHz SiO v=0 J=2-1 line toward Orion-KL with 0.45 arcsec angular resolution. The maps indicate that radio source I drives a bipolar outflow into the surrounding molecular cloud along a NE--SW axis, in agreement…
We present high angular resolution ($2\rlap.{''}8 \times 1\rlap.{''}7$) SiO J=5$\to$4; $v=0$ line observations of the OMC1S region in the Orion Nebula made using the Submillimeter Array (SMA). We detect for the first time a cluster of four…
The W40 complex is a nearby site of recent massive star formation composed of a dense molecular cloud adjacent to an HII region that contains an embedded OB star cluster. The HII region is beginning to blister out and break free from its…
The distribution of dust and molecular clouds in the direction of Galactic longitudes 132--158 deg and latitudes pm 12 deg is investigated. The maps of dust distribution in the area were plotted from the following surveys: the star counts…
The role of feedback in the self-regulation of star formation is a fundamental question in astrophysics. The Orion Nebula is the nearest site of ongoing and recent massive star formation. It is a unique laboratory for the study of stellar…
Star formation feedback can drive large-scale, multi-phase galactic outflows. The dynamical and thermodynamical interaction between the hot and cooler phases is a prime focus of both observational and theoretical work. Here, we analyze…
LDN 1615/1616 and CB 28 (hereafter, L1616) together form a cometary globule located at an angular distance of about 8 degrees west of the Orion OB1 association, aligned roughly along the east-west direction, and showing a distinct head-tail…
The L1551 molecular cloud contains two small clusters of Class 0 and I protostars, as well as a halo of more evolved Class II and III YSOs, indicating a current and at least one past burst of star formation. We present here new, sensitive…
We present initial results from a survey of the Orion A and B molecular clouds made with the InfraRed Array Camera (IRAC) onboard the Spitzer Space Telescope. This survey encompasses a total of 5.6 square degrees with the sensitivity to…
Context: To follow the early evolution of stars we need to understand how young stars accrete and eject mass. It is generally assumed that the FU Orionis phenomenon is related to the variations in the disk accretion, but many questions…