| Show guide to elIce by permission of POPULAR SCIENCE now HOW AUB ARE TIIE SEASONS CAUSED the axis of 0 the earth which Is the line from pole to pole around which the earth rotates is tilted a little As the earth moves around the sun in its yearly orbit the northern halt half of the earth Is tilted toward the surk sun tor for halt half the year and away from t the h e sun run tor for the other halt half when it Is t tilted toward the sun we have summer e r when it Is tilted the other way we have winter the other halt half of the earth the southern hemisphere has its 6 seasons afons reversed because it Is inclined toward the sun when our halt half Is inclined away from it and vice versa the south american summer Is our winter their winter Is our summer ABC ta THE 1 r WINTERS MORE SEVERE THAN USED TO BE vo no careful scientific records show no change at least within the last century or two some winters rs are severe others are less so they have always been this way ARE THERE intelligent BEINGS ON MARS the answer to this question depends upon what we think of the so called canals if the canals really are straight lines stretching across the surface of mars they are not likely to be accidental we must conclude that some intelligent beings made thern them either because they wanted to make the best use of scanty water or lor for some other purpose but man many y astronomers think that the canals are not real that the idea of their stra I 1 Is an optical illusion this leaves the question of the habitation ot of mars till still open I 1 WHY CANOT CANNOT YIE WE GO TO 10 MARS MAKS IN AN A AlK N because there Is not air between us and nd mars nothing but empty space an airplane requires air to hold it up CAN ME communicate WITH BLAHS ir ii to 10 BE BC INHABITED there Is no physical difficulty about it we could build lights ahat could bo be seen on mars probably we could produce radio that would reach it cheth er cr we could make ours ourselves cl understood by creatures with minds totally unlike ours Is another question ARE AKE OTHER PLANETS BESIDES MARS SUPPOSED acl POSED TO BED BEB INHAR INHABITED venus Is so much like the earth that it has been suggested as a pos possible bible home 1 of life ilia but very little Is known about this question one way or the other WRY WHY DOCS THE MOON SHINE because it reflects back to us the sunlight s aleh falls on it as a mirror would WHY DOES TUE MOON SEEM TO age SHAPE risom TIME TO mie since it shines by reflected sunlight lit only that halt half ot of it which Is toward the sun Is bright the moon revolves just juet ome sometimes times dark As the moon turns the might bright part of 0 it seems to change its hape put if U you look closely you can call aten see the dark part also though more faintly WHAT IS THE MOON MILDE MADE OF it seems to be made of rocks about like those of the earth it is not quite so heavy as the earth 1 in proportion to its size its average specific gravity being only about throe three fifths as aa much as the earth CAN TILE im DATE OF THE NEW I 1 NOON BE PREDICTED since the movements of the moon end and ot of the earth are known very exactly astronomers can calculate just when the par part bof ot the m moon 0 n that Is turned toward us will beg begin I 1 n t to 0 be lit up by the sun this is the new moon WHY IS TRE THE MOON SOMETIMES SEES IN THE DAYTIME the full moon Is always visible in the daytime when it Is above the horizon and not hidden by clouds daylight aim simply ply mates makes it less noticeable |
