that is one light year
All electromagnetic radiation travels at the same speed. We usually call it "the speed of light" but it's the same for all other forms of electromagnetic waves.
We call that ionizing radiation.
I call it a 'photon'.By the way, the photon has zero rest mass, but when it travels at the speed of light ...which it always does ... it has some mass.
Well, you might just put it in a separate category, and call it "light energy". But it is probably better to place it in the broader category of "electromagnetic waves".
I call it star light. Some more erudite folks might refer to it as stellar electromagnetic radiation.
Waves, as in water, or electromagnetic radiation. Even a beam spreads out, due to diffraction.
All electromagnetic radiation travels at the same speed. We usually call it "the speed of light" but it's the same for all other forms of electromagnetic waves.
We detect electromagnetic radiation in a narrow band of frequencies that we call "visible light" with our eyes. We can feel a broader spectrum of electromagnetic radiation that we call "heat". (There are some overlaps.) We can build tools that detect ANY frequency of electromagnetic radiation, and display that in any format we select.
We call that ionizing radiation.
An electromagnetic wave, such as light or radio waves, can travel through empty space because they do not require a medium to propagate. This is due to their unique properties of electric and magnetic fields oscillating in tandem at right angles to each other.
The ones we call 'X-rays' and the ones we call 'gamma rays'.
The ones we call "gamma rays" do. Their frequency is so high that in the time of one cycle, light travels only a distance similar to the size of an atom.
A radiowave is an example of electromagnetic radiation. What most humans call light - what is produced by the sun or a light bulb - is actually called visible light. Visible light is another form of electromagnetic radiation, but with higher energies. Scientists use the word light as a substitue for the whole generalization of every kind of electromagnetic radiation.
That is called a light-year.
The common definition of 'light' (visible) is electromagnetic radiation visible to the human eye. It is only a small part of what is known as the 'electromagnetic spectrum' - which is the range of wavelengths of all possible electromagnetic radiation. Light is electromagnetic radiation, as reported. But, even though it behaves like a wave, it also behaves as a particle. We can call a particle of light a photon. Light has two identities, a "duality" of sorts, that is called wave-particle duality. That's about as simple as it can get. Light is called a "wavicle" by some, and for reason that it displays qualities of both a wave and a particle.
I call it a 'photon'.By the way, the photon has zero rest mass, but when it travels at the speed of light ...which it always does ... it has some mass.
The transfer of energy by electromagnetic waves is called electromagnetic radiation. Light, radio waves and X-rays are a few other examples of this radiation phenomenon. The Transfer process is the "flow" of particles from one location to another. The best visual example is the transfer of "heat" from one source to another.