New Britain herald., 1930-09-26
Pictures of Real Solar Body Projected On Counterpart and Re- taken From Desired Angles - Comparison With 50 Years Ago Pos sible.

Mt. Wilson, Cal. Sept. 26 P)-- Mapping the moon by a new typd of astronomical survey began to-| day at Mt. Wilson observatory.
 An adoption of airplane map making photography gives views equivalent to swinging the astron- omical cameras a few thousand miles out into space to get more di- rectly above side areas of the moons face, something impossible from earth.
 The mapping is expected to clear up a century-old controversy wheth- CT the moons face is changing and to help geologists-~ discover more about the nature and causes of the moons scenic wonders.
 The map is the latest develop ment in the work of the Carnegie Institutions committee on study of surface features of the moon. The committee members are Doctors W. S. Adams, F. G. Pease, and Edison Pett of Mt. Wilson observatory; Doctors J. P. Buwalda and Paul S. Epstein of California Institute of Technology; Dr. H. N. Russell of Princeton. and Doctors A. L. Day and F. E. Wright of the Geophysi- cal Laboratory of Washington. Dr. of the work.
 PhQgraph Artificial Moon
 A miniature artificial" moon, a globe IS inches in diameter. is set up in a clearing in the pines on top Mt. Wilson, alongside the great 1Oo-inch telescope. The clearing resembles an open air theater.
 At night moon photos are pro- 3ected with 1000 candlepower beam upon the globe, which is a curved instead of ordinary fiat screen. The globe glows realistic ally in the black shadows of the pines. but with a thousand times tha>detail seen by the eye looking at the real moon.
 The astronomers can step off to one side and photograph this arti- hcial moon just as if it were the real one. But 1t is no ordinary photography.
 Instruments Very Delicate
 Much Of the past year was spent perfecting the instruments that shoot light beams four times across the clearing, distance of 1855 feet, which is the focal length" of the 100 inch telescope. Their accuracy appears from the fact that in the Carnegie Institution astrophysical laboratory in Pasadena where they were developed. the instruments could not be used because Of traffic tremors in the ground.
 The pictures from the side straighten out the distortion photo graphs of shapes of craters and peaks near the edge of the moon. This rectiication is useful to geolo- gists in determining whether these typographical features were caused by volcanic action. meteors, or something else.
 The real moon continually mods with a motion called libration. The consequence is that no two ordinary photos are likely to be exactly the same. But with the artificial moon the ''libration" is controlled so that photos Of the real moon can be projected section by section in their proper positions on the artificial moon, and then re-photographed to build up cortect map.
 To Make Comparisons
 Old moon pictures also will be projected showing the satellite as it appeared 50 and 75 years ago, com parison of these and recent photos Is expected to settle the controversy about the moons face lifting.
 After being e-photographed from the same angle, the old and new pictures will be compared by the blink" system which was used by the American army in the world war to detect camoufage. The blink" will show any slight changes which may have taken place on the moons surface.
 The corrected map gives scien- tists an accurate base for the studies they are making of the moons surface a square mile at a time.-
 MANDELIi FIGHTS TONIGHT