Convert wavelength in terametres to wavelength in hectometres Online | Free frequency-wavelength Converter

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.

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.