guide to scie science fice WHAT IS THE SUN fiade OF 01 the spectroscope shows that it Is made of the same chemical elements which we find on earth but the sun Is so hot that most of these elements iron lor for instance are in the form ol of gases HOW LARGE IS THE ape SUN it Is miles mies in diameter over one hundred times as thick as the earth the vo volume ume of the sun is about a million and a quarter times more than that of the earth WHY DOES THE SUN SHINE because it Is hot sunlight Is the same thing as the light from a piece of white hot metal except that it Is ie on such a tremendously larger scale WILL THE SUN EVER BURN ITSELF OUT possibly but not tor for a very long time probably bly not for many billions of years the sun bun does not get its heat by burning up as we bum coal there Is reason to believe that much of the heat comes from the explosion or change of the atoms ot of matter and this means that vast stores of energy are still available tor for the sun to use it may be even I 1 that the sun Is getting hotter instead 0 ol 01 I 1 colder HOW HOT IS THE SUN about degrees fahrenheit for comparison melted iron Is about 2800 degrees the oxy hydrogen blowpipe used in melting gold may get as hot as degrees the hottest place in an electric arc lamp may reach degress or a lit tie over WHAT ARE SUNSPOTS SUN SPOTS places in which the sun Is cooler and does doer not give out quite so much heat and light they are believed to be caused by great whirling storms in the surface layers of the sun some of them are large enough tor for live five or six spheres like the earth to be dropped inside the whirling center of the storm WHAT GAS WAS discovered IN THE SUN IT WAS KNOWN ON EARTH helium the inflammable noninflammable non gas now used tor for filling airships this wets was discovered in the sun in 1868 by the spectroscope tro scope but was not found anywhere on earth until 1895 HOW DOES HEAT BEAT GET TO US FROM THE SUN it comes as radiant heat beat radiant heat la Is a kind of ether waves the same as light except that the waves are longer and are not visible to our eye WHY DOES SPACE OUTSIDE THE EARTH REMAIN COLD AL ALTHOUGH TH 0 UGH THE SUN IS SHINNING SHINING THROUGH ITT IT space transmits the ether waves of radiant heat beat it does not absorb them only things that absorb the rays are warmed by them our hand absorbs them and that Is why sun sunshine hine feels warm to it HOW MUCH ENERGY DOES THE EARTH RECEIVE FROM THE SUN one square toot foot ot of surface directly exposed to the sun bun receives in scientific jig ures about 1800 calories ot of heat per minute the heat beat received from the sun by the entire surface of the earth la Is equivalent to the burning of about tons ot of coal per minute WOULD IT BE POSSIBLE TO STORE UP SUNLIGHT DURING THE DAYTIME AND USE IT AT NIGHT FOR illumination there Is nothing scientifically feally impossible about this but no one has invented a way to do it some borne ot of the luminous paints store sunlight to a slight extent but they utilize only a millionth part ot of the solar energy or even less WHAT IS THE LAW OF gravitation the ine law that all matter attracts all other other matter the sun eun attracts the earth the earth attracts the moon it can be proved by delicate instruments that two lead balls in the scientists Is laboratory bor atory attract each other the amount ol of the attraction increases in proportion to the amount or of matter and decreases in proportion to the square of the distance between the attracting bodies IS 19 THERE ANY PLACE WHERE THINGS WEIGH NOTHING strictly sp aking there Is not though at the center ol of the earth things would weigh very little weight Is due to the attraction of gravity at the center ot of the earth the attraction due to the matter ot of the earth would disappear but there would still be some slight weight due to the attraction of gravity ot of the sun the moon and the other heavenly bodies