Show M am M weekly e guide to science by permission of POPULAR SCIENCE MONTHLY CAN THE BE rOHE TOLD BY THE STARS it e cannot a annot ac ime wa d md M d do ha 0 ano not t believe that it c can n a and no one has oer ever been able to prove the contrary Is HAT IS THE SOLAR SYSTEM it Is made up ot of our sun and the planets which revolve about it there are eight I 1 planets mercury Iter cury venus the earth mars jupiter saturn neptune and uranus there are albo several hundred tiny planets the largest only y miles tn ill diameter which travel in orbits between mars and jupiter these are too small email to be seen eeck except through powerful telescopes DOES THE STAND STAN D STILL olf OB DOES IT MOVE As viewed from the earth the sun stands still we revolve around it but but star elars a it t it if the sun were viewed from the would be seen to move the sun is merely one star it moves as the others do with reference to the center point ot of the whole cloud ot of known stars the sun moves about 13 miles a second and of t course the earth and the whole solar system go along with it WHO discovered THAT TUB THE EARTH REVOLVES AROUND THE SUN nicholas copernicus who published his bis discoveries in 1543 A few 01 of the philosophers of ancient greece especially pythagoras somewhat similar ideas but ago r as had did not work them out clearly WHAT WAS THE FIRST IMPORTANT DISCO MillY MADE WITH THE TELESCOPE the discovery of t the he moons ot of jupiter by galileo on january ry 7 1610 this discovery cy proved the theory that the file earth and the other planets revolve around the sun and displaced the theory that the earth was the center ot of the universe a theory which had bad been accepted by every body for nearly two thousand years be e fore ore gallico Gali leos s discovery CLIs covery KHY DO THE PLANETS HOLD TOGETHER IN THE OLAR SOLAR J SYSTEM INSTEAD OF FLYING OFF INTO SPACE because of the attraction ot of gravity ot of t the h e sun it if you have a ball tied to the e end n d run ol 01 a string you can whirl the ball around your head bead and the string will keep it irom from flying away just ho the planets whirl around the sun the attraction of gravity taking the place ot of the string HOW FAR AWAY IS THE SUN the distance varies slightly because I 1 the orbit ol of the earth Is not quite round the nearest we ever come to the sun Is miles the farthest away Is miles the average distance Is miles an airplane flying night arid and day at two hundred miles arx an hour would need a little over fifty two years to fly from the earth to the sun HOW FAR DOES THE EARTH amole EACH DAY IN ITS JOURNEY AROUND THE nearly miles about eighteen e ight cell and one halt half miles per second |