Convert wavelength in exametres to wavelength in hectometres 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.

Describing Very Low Frequency Radio Waves

A hectometre (hm) is a unit of length equal to 100 metres, and it is used to describe very long wavelengths in the Very Low Frequency (VLF) and Low Frequency (LF) bands of the electromagnetic spectrum. Wavelengths in the hectometre range correspond to frequencies between approximately 3 kHz and 3 MHz. These long wavelengths are typically used for maritime navigation, military submarine communication, AM radio broadcasting, and time signal transmissions.

For example, a signal at 300 kHz has a wavelength of 1 kilometre, or 10 hectometres, and a signal at 1 MHz corresponds to 3 hectometres. These long wavelengths have the unique ability to travel long distances and penetrate water and the ground, which is why they are used in submarine communications and emergency broadcast systems.

Using hectometres to express wavelength offers a practical scale for understanding wave propagation over great distances. It also aids in antenna design, where very large antennas—often hundreds of metres long—are needed to efficiently transmit or receive these frequencies. Understanding wavelength in hectometres is important in geophysics, radio astronomy, and large-scale communications infrastructure.