Electromagnetic radiation of frequency ν, wavelength λ, in free space obeys: € λυ=c c = speed of light Individual photons have energy: € E=hν h = Planck’s constant Energies are often given in electron volts, where: € 1 eV€= 1.6×10−12 erg=1.6×10−19 J h=6.626×10−27 erg s c=3.0×1010 cm s-1. type of radiation is lower in energy, and is easier to protect astronauts and electronics from with shielding materials. The types of radiation fall into two main categories: particulate and electromagnetic.

The relationship between the wavelength, λ, and frequency, ν, of EMR is based on the following formula, where c is the speed of light: Note that frequency, ν, is inversely proportional to wavelength, λ. Finally, solar energetic particles are released by the Sun in what are called solar particle events.

7 types of electromagnetic radiation. Particulate radiation consists of particles that have mass and energy, and may or may not have an electric charge. Wave Model of Electromagnetic Radiation In the 1860s, James Clerk Maxwell (1831–1879) conceptualized electromagnetic radiation (EMR) as an electromagnetic wave that travels through space at the speed of light, c,whichis3x108 meters per second (hereafter referred to as m s-1) or 186,282.03 miles s . For convenience, we divide electromagnetic radiation into different regions—the electromagnetic spectrum—based on the type of atomic or molecular transition that gives rise to the absorption or emission of photons (Figure 10.3). Figure 1 presents an overview of the electromagnetic spectrum; section 3 will go into greater detail on the different types of radiation.

visible light is merely a part of the whole spectrum of electromagnetic radiation, extending from the radio waves to cosmic rays. Wave Model of Electromagnetic Radiation. A useful relation for Primary Astrophysical Processes Producing Electromagnetic Radiation!

The frequency and wavelength of electromagnetic radiation vary over many orders of magnitude. Light The visible region of the spectrum is the one most familiar to us, because as a species we have adapted receptors (eyes) that are sensitive to the most intense electromagnetic radiation emitted by the Sun, the closest extraterrestrial source.
All these apparently different forms of electromagnetic radiations travel at the same velocity but characteristically differ from each other in terms of frequencies and wavelength (Table 1). Examples of particulate radiation include alpha particles, protons, beta particles, and neutrons.
Sound and visible light are familiar forms of radiation; other types include ultraviolet radiation (that produces a suntan), infrared radiation (a form of heat energy), and radio and television signals. Radiation is described by its type and energy.