They will be extremely helpful in understanding masers and the physics of the masing regions and also for measuring the abundance of water, probably the most important interstellar molecule. Also discovered recently is a new phase of stellar evolution, which occurs for red giant stars just before they completely lose their envelope to form planetary nebulae. It is manifest as a very fast molecular wind which is detected at the CSO as a wide spectral feature in carbon monoxide emission. The CSO has been used for studies of young stellar objects and protostars where disks around optically visible T Tauri objects and imbedded objects such as L1551 have been studied. General mapping and spectroscopy studies of the structure of the interstellar medium with very high signal to noise and large dynamic range in the size of the maps, have shown that the velocity distribution in molecular clouds is non-Gaussian and this has been shown to be due to intermittency, a fundamental property of turbulence.
Many galaxies contain dust and molecular gas, which can be studied in the submillimeter.
Nearby galaxies are being mapped to analyze the relationships between optical, HI, dust and molecular emissions. A particularly interesting case is the radio galaxy Centaurus A which is an elliptical galaxy with a dust lane and an active nucleus. The CSO has been able to map the molecular gas and show that the spectral profiles of the disk can be deduced from the gravitational potential of the elliptical galaxy. Spectra towards the nucleus show what may be infalling material to the central object. Molecular gas has been investigated in several other elliptical galaxies.