Convert attohertz [aHz] to wavelength in terametres Online | Free frequency-wavelength Converter

Measuring Ultra-Low Frequencies

The attohertz (aHz) is an extremely small unit of frequency equal to 10⁻¹⁸ hertz, or one cycle per 10¹⁸ seconds (about 31.7 billion years). This unit is used to describe ultra-low frequency phenomena that occur on cosmic or geological timescales, far beyond everyday human experience.

Attohertz frequencies are relevant in cosmology, astrophysics, and geophysics, where they help scientists study processes that evolve over billions of years. For example, gravitational waves generated by massive cosmic events or the oscillations of the Earth’s magnetic field can be characterized by frequencies in the attohertz range. These waves have enormous wavelengths, often spanning millions or billions of kilometres.

Because the attohertz corresponds to such a long period between cycles, it is mostly used in theoretical research rather than practical applications. Understanding phenomena at this scale gives insight into the fundamental workings of the universe, including the slow evolution of cosmic structures, the expansion of space-time, and the early conditions following the Big Bang.

Cosmic Scales of Electromagnetic Waves

A terametre (Tm) is equal to 1 trillion metres (10¹² m), an enormous unit used to describe wavelengths on an interplanetary or even interstellar scale. Such colossal wavelengths correspond to extremely low frequencies in the picohertz to femtohertz range and are primarily relevant in astrophysics, cosmology, and gravitational wave studies. At this scale, electromagnetic or gravitational waves can span distances comparable to the size of the solar system or beyond.

For example, a frequency of 1 femtohertz (10⁻¹⁵ Hz) corresponds to a wavelength of approximately 300 terametres, or 300 billion kilometres — about twice the distance from the Sun to Pluto. These wavelengths are far beyond practical terrestrial communication but are important for understanding phenomena like primordial gravitational waves, cosmic microwave background fluctuations, and large-scale cosmic structures.

Using terametres to express wavelength helps scientists conceptualize and study the vast, slow oscillations that shape the universe over billions of years. These extreme wavelengths offer insight into the very fabric of space-time, the origins of the universe, and processes occurring on the grandest cosmic scales.