This image shows the Sun in ultraviolet light (the brighter red and yellow regions represent hot areas; the darker regions are cooler). Luckily for humans, most ultra- violet light from the Sun is absorbed by the Earth’s atmosphere; the UV light that does reach us causes sunburn, skin cancer, and other forms of skin damage. 
    Different portions of the solar atmosphere each emit light at a particular wavelength—visible, ultraviolet, radio, or x-ray. By taking photographs at only one wavelength, it is possible to “peel off” the outer layers, much like one peels an onion, and observe the Sun at different depths. The light in this image is from the Sun’s chromosphere, the region just above the photosphere that extends