CORONA OF THE SUN

Hawera Star, Volume LIII, 10 March 1934, Page 11

CORONA OF THE SUN

rpHE sun's corona is largely oxygen. Perhaps the most important astronomical discovery in recent years was announced from the research laboratories of the Harvard Observatory. Coromum is the term which has been used for the last 60 years for explaining the pearly whiteness of the sun’s corona, visible only during a total eclipse, says the “Christian Science Monitor.”

More than a year has passed since the last total eclipse, and the first information of major importance was announced when. Dr. Donald H. Men'el, of Harvard, arid Dr. Joseph C. Boyce, of Massachusetts Institute of Technology, made known that the element most prominent in the corona, previously called eoronium for want of knowledge as to its exact nature, is oxygen. The announcement of the discovery was made on a regulation observatory announcement card, the brief technical paragraph scarcely portraying the excitement and enthusiasm displayed by observatory officials. For a long time astronomers have sought to learn the nature of the corona. It was previously believed to be made up of some clement not known on earth, causing the mysterious pearly light only about one-half as bright as that of full moon.

The sun’s corona has been photographed as extending more than J 0.000,000 miles beyond the surface, and gravity is computed to be 27 times more powerful on the sun than it is on

Big Proportion Thought Oxygen

the earth. If the oxygen which makes up the corona were atmospheric in nature, the resulting pressure would be unthinkable. Though this is viewed as a great step forward, there are still many problems to be solved. Dr. Uouzel and Dr. Boyce have found that “analysis of the coronal spectrum reveals that the frequency difference between coronal lines agrees with the difference between two known high energy states of the neutral oxygen atom, which suggests that the lines are produced by combination with a higher energy state.” Interpreting the announcement, it is noted that Dr. Mongol and Dr. Boyce have made the first important step in the unravelling of an astronomical mystery that has existed since the first observations of the. corona spectra, more than 60 years ago. The radiations from the corona have been attributed to eoronium much as the light of nebulae was long attributed to the hypothetical “nebulium.” A few years ago this was solved by the discovery that the highly-ionised oxygen and" nitrogen were responsible for its radiation. Also in recent years the mysterious light of the aurora has been assigned to ionised oxygen. The present analysis identified three of the strongest coronal lines with, the, neutral oxygen atoms in the "high solar atmosphere, these atoms being in a very peculiar state of excitation. It is probable that after this important start other coronal lines will soon be interpreted.