| A | B |
|---|
| aurora | a bright display of ever-changing light caused by solar radiation interacting with the upper atmosphere in the region of the poles |
| bright-line spectrum | the bright lines produced by an incandescent gas under low pressure |
| chromatice aberration | the property of a lens whereby light of different colors is focused at different places |
| continuous spectrum | an uninterrupted band of light emitted by an incandescent solid, liquid, or gas under pressure |
| corona | the outer, tenuous layer of the solar atmosphere |
| dark-line spectrum | is produced when white light is passed through a comparatively cool gas under low pressure |
| doppler effect | the apparent change in wavelength of radiation caused by the relative motions of the source and the observer |
| electromagnetic radiation | visble light constitutes only a small part of an array of energy |
| eyepiece | a short-focal-length lens used to enlarge the image in a telescope. the lens nearest the eye |
| focus | the point where a lens or mirror causes light rays to converge |
| granule | the fine sturcture visible on the solar surface caused by convective cells below |
| nuclear fusion | the source of the sun's energy |
| objective lens | in a refracting telescope, the long-focal-lenght lens that forms an image of the object viewed. the lens closest to the object |
| photon | a discrete amount (quantum) of electromagnetic energy |
| photosphere | teh region of the sun that radiates eneryg to space. the visible surface of the sun |
| prominence | a concentration of material above the solar surface that appears as a bright archlike structure |
| proton-proton chain | a chain of thermonuclear reactions by which nuclei of hydrogen are built up into nuclei of helium |
| radiation pressure | the force exerted by electromagnetic radiation from an object such as the sun |
| radio interferometer | two or more radio telescopes that combine their signals to achieve the resolving power of a larger telescope |
| radio telescope | a telescope designed to make observations in radio wavelenghts. |
| reflecting telescope | a telescope that concentrates light from distant objects by using a concave mirror |
| refracting telescope | a telescope that employs a lens to bend and concentrate the light from distant objects |
| solar flare | a sudden and tremendous eruption in the solr chromosphere |
| spectroscope | an instrument for directly viewing the spectrum of a light source |
| spicule | a narrow jet of rising material in the solar chromosphere |
| sunspot | a dark spot on the sun, which is cool by contrast to the surrounding photosphere |
