Discovery
Prior to the Space Age, the possibility of trapped charged particles had been investigated by Kristian Birkeland, Carl Stormer, and Nicholas Christofilos. The existence of the belt was confirmed by the Explorer 1 and Explorer 3 missions in early 1958, under Dr. James Van Allen at the University of Iowa. The trapped radiation was first mapped out by Explorer 4, Pioneer 3 and Luna 1.
The term Van Allen belts refers specifically to the radiation belts surrounding Earth; however, similar radiation belts have been discovered around other planets. The Sun itself does not support long-term radiation belts, as it lacks a stable, global dipole field. The Earth's atmosphere limits the belts' particles to regions above 200–1,000 km, while the belts do not extend past 7 Earth radii RE. The belts are confined to a volume which extends about 65° from the celestial equator.
Read more about this topic: Van Allen Radiation Belt
Famous quotes containing the word discovery:
“However backwards the world has been in former ages in the discovery of such points as GOD never meant us to know,—we have been more successful in our own days:Mthousands can trace out now the impressions of this divine intercourse in themselves, from the first moment they received it, and with such distinct intelligence of its progress and workings, as to require no evidence of its truth.”
—Laurence Sterne (1713–1768)
“Your discovery of the contradiction caused me the greatest surprise and, I would almost say, consternation, since it has shaken the basis on which I intended to build my arithmetic.... It is all the more serious since, with the loss of my rule V, not only the foundations of my arithmetic, but also the sole possible foundations of arithmetic seem to vanish.”
—Gottlob Frege (1848–1925)
“The gain is not the having of children; it is the discovery of love and how to be loving.”
—Polly Berrien Berends (20th century)