Convert wavelength in exametres to nanohertz [nHz] Online | Free frequency-wavelength Converter

The Vastest Scales of Cosmic Waves

An exametre (Em) is equal to 1,000 petametres (10¹⁸ metres), representing one of the largest units of length used to describe the longest electromagnetic wavelengths and gravitational waves in the universe. At this scale, wavelengths correspond to frequencies in the zeptohertz (10⁻²¹ Hz) range and lower, which are incredibly slow oscillations occurring over billions of years and spanning distances larger than entire galaxy superclusters.

For example, waves with a frequency of around 1 zeptohertz have wavelengths on the order of 300 exametres. These enormous waves are primarily theoretical and are significant in cosmology and astrophysics for studying the large-scale structure of the universe, primordial fluctuations from the Big Bang, and the behavior of space-time itself.

Using exametres to express wavelength helps scientists conceptualize the almost incomprehensible vastness of the cosmos. These extreme wavelengths provide key insights into the fundamental nature of the universe, including gravitational wave backgrounds and the evolution of cosmic structures on the grandest scales.

The Realm of Extremely Slow Oscillations

The nanohertz (nHz) is a unit of frequency equal to 10⁻⁹ hertz, meaning one cycle occurs every 1 billion seconds—about 31.7 years. This incredibly low frequency is important in fields like astrophysics, cosmology, and geophysics, where slow periodic phenomena unfold over decades to centuries.

Nanohertz frequencies are often associated with gravitational waves produced by supermassive black hole binaries orbiting each other over many years. These ultra-low-frequency waves have immense wavelengths, spanning light-years across space. Pulsar timing arrays, which monitor the precise arrival times of pulsar signals, are used to detect such nanohertz gravitational waves, offering insights into galaxy evolution and cosmic structure.

On Earth, nanohertz frequencies can describe long-term oscillations in the geomagnetic field or climate cycles. Studying these slow frequencies helps scientists understand gradual changes in planetary environments and the universe.

Although nanohertz waves are far below everyday human perception and technological applications, they are critical for unraveling the universe's slowest dynamics. Using nanohertz as a unit helps researchers quantify and analyze these grand-scale processes, linking time scales from decades to cosmic evolution.