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The first JWST spectrum of the GRB 221009A afterglow

Gamma-ray bursts are the most energetic and luminous events known to occur in the Universe. Short-lived flashes of gamma rays that typically last from a a tenth of a second to less than an hour, gamma-ray bursts may for a ...

Temperature-dependent adaptations of whale shark vision

Researchers in Japan led by the RIKEN Center for Biosystems Dynamics Research, Kobe and Osaka Metropolitan University, Osaka, have discovered that whale shark vision has uniquely temperature-dependent adaptations unseen in ...

Identifying organic compounds with visible light

Researchers from the Universidad de Santiago de Chile and the University of Notre Dame, working with machine learning, have devised a method to identify organic compounds based on the refractive index at a single optical ...

NASA to measure forest health from above

In places across the U.S., tree cover is shrinking—forests are burned by wildfires on the West Coast and drowned by rising sea levels along the East. From the ground, it's hard to assess the scale of the losses and the ...

Image: Hubble observes jellyfish galaxy JO201

A "jellyfish galaxy" with trailing tentacles of stars hangs in inky blackness in this image from the NASA/ESA Hubble Space Telescope. As jellyfish galaxies move through intergalactic space, gas is slowly stripped away forming ...

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In physics, the wavelength of a sinusoidal wave is the spatial period of the wave – the distance over which the wave's shape repeats. It is usually determined by considering the distance between consecutive corresponding points of the same phase, such as crests, troughs, or zero crossings, and is a characteristic of both traveling waves and standing waves. Wavelength is commonly designated by the Greek letter lambda (λ). The concept can also be applied to periodic waves of non-sinusoidal shape. The term wavelength is also sometimes applied to modulated waves, and to the sinusoidal envelopes of modulated waves or waves formed by interference of several sinusoids.

Assuming a sinusoidal wave moving at a fixed wave speed, wavelength is inversely proportional to frequency: waves with higher frequencies have shorter wavelengths, and lower frequencies have longer wavelengths.

Examples of wave-like phenomena are sound waves, light, and water waves. A sound wave is a periodic variation in air pressure, while in light and other electromagnetic radiation the strength of the electric and the magnetic field vary. Water waves are periodic variations in the height of a body of water. In a crystal lattice vibration, atomic positions vary periodically in both lattice position and time.

Wavelength is a measure of the distance between repetitions of a shape feature such as peaks, valleys, or zero-crossings, not a measure of how far any given particle moves. For example, in waves over deep water a particle in the water moves in a circle of the same diameter as the wave height, unrelated to wavelength.

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