Show 1 I ONE SIDE IDE OF MERCURY IS HOT HOTI V V By Ely DAVID DIETZ N NEA EA Service Writer c V l MT WIL WILSON ON Cal Ca April 17 On Oni side of ot the pl planet Mercury is probably red hot while the other Is Isas its as cold a as it is possible for anything any any- thing In in th the universe e to get set This Is ts the strange situation brought to light by the recent measurements of ot the surface temperature of Mercury Mercury Mer Mer- cury by y Dr S S. B D Nicholson and arid Dr Edison Pettit p t lt of the Mt r Wilson Wil wn son observatory V Our observations show that the surface temperature On n Mercury directly under the suns sun's rays rays rays- that rays that hat Is s at the point where here it is Is noon noonon on Mercury Mercury Mercury-Is Is degrees degree l Fahren n belt heit Dr Pettit V told me This is the melting point of ofin in ind 5 V V I If there w were re any an tin l lead ad or orInc pine Inc Incon on Mercury at the thethis spot where this temperature obtains th they y would exist only In the molten form V Thc These Thee e observations give gl Mercury 11 a still sUlI more unusual position among the tue pl planets nets revolving ng around the tre sun un than it formerly possessed Th There a are e eight planets revolving around the sun of which of gourse our earth Is Js one Mercury Is Js the sm smallest of pf V the eight the closest to tIle the sun and rind the cne lne which possesses possesse the most ec eccentric or orbit that orbit lt that I is th the tha one whose orbit Is Js 8 most mot flattened or distorted die dis from the shape of ot a circle V Due to th the fact tact that Mercury is closer to the tho sun than the earth we do not always see all of ot Jt Its lighted side from the earth arth Consequently Con In the telescope Mercury Mercury Mer Mer- cury curl appears to go ga through phases like the moon moon When It Is a crescent cres eres- cen cent It means t that at part of th the ht lighted d side and p part rt of t the Je dar dark side id are turned towards the earth A measure of ot the temperature at the crescent phase gives a an average ayera e of 60 degrees Dr Pettit says We Ve are convinced this rapid decline In the temperature measurement that the he theory that Mercury always keeps keps the same face lace turned toward th the sun nun Just as the always keeps the same face toward the tha earth Js is correct We believe therefore that w while the face toward the sun may be red hot the temperature of ot the other face is that of the so called absolute S1 zero zero that that is s the tem tern of empty spa space e pr 1 45 degree de do- green grees F Fahrenheit below zero hW We a tIC aio e also convinced that there Is no no atmosphere f upon Mercury 1 It goes gOE without saying that life as we know ft Jt t would be bleon I O Mercury I V 1 i It Itt i i t V V v- v Dr Pettit and Dr Nicholson have been making their measurements of the t temperature of Mercury with witha a IJ device known as the thermocouple thermo thermo- couple This consists of a juncture of two different metals within a vacuum cell This cell Is s at the enc en end of a 0 telescope and arid the image of the planet focused on it This heats beats the Juncture and generates generates generates gener gener- ates an nn electric current of less than thana a Q billionth of at a an ampere amper A delicate delicate delicate deli deli- cate ammeter measures this current and t the e temperature of ot the J. J plant planet plantis lan t tI I Is calculated from it t |