Linked from
The 11 pages that link to Maser, each with the reason it gives.
LaserCompared with: Masers use the same basic principle at longer wavelengths than optical lasers.
Stimulated emissionBroader topic: It applies the same emission mechanism at microwave frequencies.
Hydrogen maserNarrower topic: The hydrogen maser is an atomic-beam maser using hydrogen atoms.
Alexander ProkhorovBroader topic: Prokhorov’s foundational work helped establish molecular masers.
Charles H. TownesRelated: Townes and colleagues built the first working maser in 1953.
Messier 77Related: Water masers in Messier 77’s nucleus trace gas orbiting close to its black hole.
CW LeonisRelated: Maser emission from circumstellar molecules can trace winds around evolved stars.