Planets form and obtain their compositions in disks of gas and dust around young stars. The
chemical compositions of these planet-forming disks regulate all aspects of planetary …

Despite the generally hostile nature of the environments involved, chemistry does occur in
space. Molecules are seen in environments that span a wide range of physical and chemical …

We review current understanding of star formation, outlining an overall theoretical framework
and the observations that motivate it. A conception of star formation has emerged in which …

Understanding the formation of stars in galaxies is central to much of modern astrophysics.
However, a quantitative prediction of the star formation rate and the initial distribution of …

This paper analyzes optical and infrared photometry of pre-main-sequence stars in the
Taurus-Aunga molecular cloud. More than half of the stars in our sample have excess near …

Context. Core condensation is a critical step in the star-formation process, but it is still poorly
characterized observationally. Aims. We have studied the 10 pc-long L1495/B213 complex …

Cold dark clouds are nearby members of the densest and coldest phase in the Galactic
interstellar medium, and represent the most accessible sites where stars like our Sun are …

Context. Density and velocity fluctuations on virtually all scales observed with modern
telescopes show that molecular clouds (MCs) are turbulent. The forcing and structural …

Aims. Photodissociation by UV light is an important destruction mechanism for carbon
monoxide (CO) in many astrophysical environments, ranging from interstellar clouds to …

Recent discoveries of extrasolar planets and new direct evidence for protoplanetary disks
around young stars have had a major impact on our understanding of star and planet …