Convert wavelength in nanometres [nm] to wavelength in petametres Online | Free frequency-wavelength Converter

Measuring Light and Electromagnetic Waves

A nanometre (nm) is a unit of length equal to one billionth of a metre (1 nm = 10⁻⁹ m) and is commonly used to express wavelengths of light and other electromagnetic waves. In this context, nanometres provide a convenient scale for describing phenomena that occur at the atomic and molecular level. Visible light, for example, spans wavelengths from about 380 nm (violet) to 750 nm (red). Ultraviolet (UV) light has shorter wavelengths, typically between 10 nm and 400 nm, while infrared (IR) light has longer wavelengths, from about 750 nm to 1,000,000 nm.

Wavelengths in nanometres are critical in fields like optics, photonics, spectroscopy, and nanotechnology. They determine the energy and color of light, how it interacts with matter, and how it can be manipulated in devices like lasers, fiber optics, and solar cells. Shorter wavelengths (in the UV or X-ray range) carry more energy and are used in applications such as medical imaging and semiconductor fabrication. Understanding and working with wavelengths in nanometres allows scientists and engineers to explore and control the behavior of light at extremely small scales—down to the size of atoms and molecules.

The Scale of Interstellar and Cosmological Waves

A petametre (Pm) equals 1,000 terametres (10¹⁵ metres), representing unimaginably vast distances that describe the longest electromagnetic wavelengths in the universe. These wavelengths correspond to frequencies in the attohertz (10⁻¹⁸ Hz) and lower ranges, which are mostly relevant in cosmology, astrophysics, and the study of gravitational waves and large-scale cosmic phenomena.

For context, a frequency of 1 attohertz (10⁻¹⁸ Hz) corresponds to a wavelength of approximately 300 petametres. This scale is far beyond any human-made signals and reflects waves that stretch across entire galaxies or even clusters of galaxies. Such waves help scientists study the cosmic microwave background (CMB) fluctuations, the large-scale structure of the universe, and primordial gravitational waves created shortly after the Big Bang.

Using petametres to measure wavelength allows researchers to grasp the vastness of these cosmic oscillations and the slowest processes influencing the universe’s evolution. These extreme wavelengths provide crucial insight into the origins, expansion, and ultimate fate of the cosmos.