Show Aviator Who Reaches Moon If Ever Will Know Kind of Rocks Hell He'll Land LandOn Landon LandOn On Through New Scientific Studies Light Reflected From Face of Satellite Analyzed by Earth Dwellers Bv F. F B. B COLTON Associated Press Science Writer WASHINGTON ASHINGTON V Dec 22 If 22 If a flier ever reaches the moon in a a. rocket he le will b be able to know know-in know In advance the kinds o of rocks on which his space ship will land How scientists scientist have learned what the moon is made of oC without actually actually actu actu- ally going there was demonstrated today at the opening o of the annual exhibition of research activities of oC the Carnegie institute of Washington Another exhibit showed new photographs photo graphs of ot orthe the milky wa way which have led ed led astronomers to decide the great system star to which the th carth earth bel beI be- be l I ng Is 3 much ch smaller than formerly bc believed ed e The rocks on the moon are identified fled fied by analyzing moonlight ex explained ex cx- Dr Fred E. E Wright He showed a machine recently put to use me for the he first time in stud studying ing the moons moon's face which shows it is mostly powdered with pumice and volcanic ash h Moonlight is sunlight reflected rom from the moons moon's rocks Any single kind of or rock on both the earth and moon reflects light in the same way Granite reflects it for instance differently dif dl- from limestone or pumice On earth scientists can study how light Ight acts when reflected rene ed from fr m dif dif- if- if ferent terent kinds of oC rock Then studying moonlight they tell from what kinds of rock it was as reflected Rocks affect light waves wa by what scientists call spectral reflection This means certain colors In hi a light ray are reflected more strongly by some than by others Rocks also cause an effect on light wa waves called polarization polarization po The scientists measure both A large map of ot the thc milky way made of oC photographs fitted together like airplane photos was exhibited by Dr F. F H. H Scares On it were large dark clouds of or dust and gas blotting out I some of or the stars These probably have caused errors in past measurements measurements measure measure- I ments of the system star-system of or which I the earth is a part pare the thc dust and gas as clouds have obscured U light ht from Crom distant dis dis- I dis-I I tant taut star clusters clusters tar measuring posts I of 01 our system star as fog dims duns a a street lamp I Diagrams on exhibition showed the sun and earth are part ofa local system tem tern of very ery hot bright stars some so large it would take light 2000 years to cross them This system Is part of or ofa a a. vast main system of ot 30 or 40 thousand thousand thousand thou thou- sand million stars shaped like a a. giant cartwheel Our sun which Is one of or these stars Is far out toward the rim of the wheel Far outside our own system star-system areat are areat areat at least other systems star spinning through space Photographs in the exhibit showed some resembling resembling bling giant Fourth of or July trailing clouds of stars Instead of or sparks Others seem more like huge balls of ot fire lire |