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Maser

physical science Maturity 9-11 Next article →

A maser is a special device that makes waves. These are called electromagnetic waves, and they are often microwaves. The name is an acronym for microwave amplification by stimulated emission of radiation.

Charles Townes and first maser
Charles Townes and first maser

This tool is very important for science. It helps us measure time and talk to things in space. Masers can even be found naturally in the stars.

Hubble Captures Vivid Auroras in Jupiter's Atmosphere
Hubble Captures Vivid Auroras in Jupiter's Atmosphere

Masers work through a process called stimulated emission. First, atoms or molecules enter an excited state. This means they have extra energy. When these atoms release that energy, they create waves. A single wave can trigger more atoms to release waves too. This makes the signal much stronger through amplification.

Hmaser
Hmaser

In a hydrogen maser, a beam of hydrogen atoms is created first. Then, a magnetic field helps select atoms in a high energy level. These atoms decay and emit microwaves inside a special cavity. This cavity reflects the waves back to keep the process going.

Scientists have been working on this idea for a long time. Albert Einstein first proposed the idea of stimulated emission in 1917. Later, Joseph Weber described how a maser might work in 1952. Around that same time, Nikolay Basov and Alexander Prokhorov also worked on the theory. In 1953, Charles H. Townes, James P. Gordon, and Herbert J. Zeiger built the first working ammonia maser. They did this at Columbia University.

Hydrogen maser
Hydrogen maser

These scientists won the Nobel Prize in Physics in 1964 for their work.

There are many different kinds of masers used today. Some use ammonia, while others use hydrogen or even liquid dyes. Scientists also use solid-state masers. In 2012, a team used a material called pentacene-doped p-Terphenyl to make a maser at room temperature. In 2018, another team used synthetic diamonds for a continuous maser. Even in 2025, researchers created a low-cost unit using an LED. These different types help us study everything from tiny atoms to huge galaxies.

Masers are very helpful in our daily lives and in deep space. They are used in atomic clocks to keep extremely precise time. This helps create the international time standard called TAI. Masers also help us listen to space. In the 1960s, the Jet Propulsion Laboratory used a cooled ruby maser to hear the Mariner IV probe. This helped the probe send pictures from Mars back to Earth. Without these tools, space communication would be much harder.

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🖼️ Images & Media (4)
File:Charles Townes and first maser.jpg
Charles Townes and first maser.jpg
File:Hydrogen maser.gif
Hydrogen maser.gif
File:Hmaser.svg
Hmaser.svg
File:Hubble Captures Vivid Auroras in Jupiter's Atmosphere.jpg
Hubble Captures Vivid Auroras in...
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