One of the most spectacular discoveries of molecular astronomy has been the detection of maser emission. The same radiation that is generated in the laboratory only with elaborate, special equipment occurs naturally in interstellar space. This intense radiation probes the smallest structures that can be studied with radio telescopes. By a fortunate coincidence maser radiation is generated in both star forming regions and the envelopes of late-type stars. The early and late stages in the life of a star are considered to be the most interesting phases of stellar evolution. Maser emission has...

One of the most spectacular discoveries of molecular astronomy has been the detection of maser emission. The same radiation that is generated in the laboratory only with elaborate, special equipment occurs naturally in interstellar space. This intense radiation probes the smallest structures that can be studied with radio telescopes. By a fortunate coincidence maser radiation is generated in both star forming regions and the envelopes of late-type stars. The early and late stages in the life of a star are considered to be the most interesting phases of stellar evolution. Maser emission has...