AUTUMNAL EQUINOX - ITS FALL
DEAN:
HEY THERE STAR GAZERS, I'M DEAN REGAS ASTRONOMY
FOR
THE CINCINNATI OBSERVATORY.
JAMES:
AND I'M JAMES ALBURY THE DIRECTOR OF THE KIKA
SILVA PLA PLANETARIUM IN GAINESVILLE FLORIDA.
WERE HERE TO HELP YOU FIND YOUR WAY AROUND
THE SKY.
OK DEAN, WHAT THE HECK ARE YOU DOING?
DEAN:
I HEARD A RUMOR THAT YOU CAN BALANCE AN EGG,
ON-END, ON THE SPRING OR FALL EQUINOXES SO
I WANTED TO TRY IT OUT.
JAMES:
ANY LUCK?
DEAN:
NOT YET.
JAMES:
(I HATE TO TELL DEAN BUT, THATS JUST AN URBAN
LEGEND.
BUT WHAT DOES HAPPEN DURING THE EQUINOX IS
TRULY AMAZING.
THE SUN RISES DUE EAST AND SETS DUE WEST).
DEAN:
AND THERE ARE 12 HOURS OF DAYLIGHT AND 12
HOURS OF DARKNESS OVER THE ENTIRE WORLD.
JAMES:
AND THE AUTUMNAL EQUNIOX IS COMING UP ON SEPTEMBER
23RD.
SO WHATS REALLY GOING TO HAPPEN?
DEAN: LETS SHOW YOU!
JAMES:
AUTUMN OFFICIALLY BEGINS AT THE AUTUMNAL EQUINOX,
SEPTEMBER 23RD,
SO GET READY FOR SOME
IN-YOUR-FACE SUNRISES AND IN-YOUR-FACE SUNSETS.
DEAN:
ON THE EQUINOXES THE SUN RISES DUE EAST
AND SETS DUE-WEST.
THAT MEANS IF YOU DRIVE TO WORK ON
A DUE-EAST ROAD AT SUNRISE THE SUN WILL RISE
DIRECTLY OVER
THE YELLOW LINE IN THE MIDDLE OF THE ROAD.
AND IF YOU DRIVE HOME AT SUNSET ON A
DUE-WEST HIGHWAY,
THE SUN WILL SET RIGHT IN FRONT OF YOU.
THAT COULD MAKE FOR
A BLINDING COMMUTE!
JAMES:
YOU ACTUALLY MIGHT NOTICE THIS DAZZLING SUNRISE
AND SUNET FOR A WEEK ON EITHER SIDE OF THE
EQUINOXES,
AND DRIVING CAN BE TREACHEROUS.
SO GET OUT YOUR SUNGLASSES AND
PUT THOSE SUN VISORS DOWN.
JAMES:
BUT WHAT ARE THE EQUINOXES ANYWAY?
WELL, THE WORD 'EQUINOX' COMES FROM THE LATIN,
'EQUI' WHICH MEANS EQUAL, AND 'NOX' WHICH
MEANS NIGHT.
SO ON BOTH THE SPRING AND FALL EQUINOXES,
THE HOURS OF NIGHT ARE EQUAL TO THE HOURS
OF DAYLIGHT.
DEAN:
YOU'VE PROBABLY LEARNED THAT AS THE EARTH
CIRCLES THE SUN, IT IS TILTED.
WHEN THE NORTHERN HEMISPHERE OF THE EARTH
IS TILTED TOWARD THE SUN, THATS WHEN WE HAVE
SUMMER.
WE GET MORE ENERGY FROM THE SUN AND HAVE LONGER
DAYS AND SHORTER NIGHTS.
JAMES:
WHEN WE'RE ON THE OTHER SIDE OF THE SUN, AND
THE NORTHERN HEMISPHERE IS TILTED AWAY FROM
THE SUN, WE GET LESS ENERGY FROM THE SUN AND
HAVE SHORTER DAYS AND LONGER NIGHTS.
DEAN:
BUT IN BETWEEN SUMMER AND WINTER WE COME
TO POINTS WHERE THE SUN FALLS DIRECTLY ON
THE EQUATOR.
AND THAT MEANS AS THE EARTH TURNS, EVERYWHERE
ON OUR PLANET RECEIVES
12 HOURS OF DAYLIGHT AND 12 HOURS OF DARKNESS.
EQUAL DAY, EQUAL NIGHT, EQUINOX.
DEAN:
IF YOU WATCH THE SUN RISE ON THE FIRST DAY
OF SPRING YOU'LL SEE THAT IT RISES DUE EAST.
BUT IF YOU WATCH THE SUN RISE EACH SUCCESSIVE
DAY AFTER THAT YOU'LL NOTICE THAT IT'LL RISE
A LITTLE BIT FARTHER NORTH OF EAST EACH SUCCESSIVE
DAY UNTIL IT REACHES IT'S FARTHEST POINT NORTH
OF EAST ON THE FIRST DAY OF SUMMER,
JAMES:
THEN THE SUN WILL SEEM TO BACK UP AND RISE
A LITTLE BIT LESS NORTHEAST EACH SUCCESSIVE
DAY UNTIL ONCE AGAIN ON THE FIRST DAY OF AUTUMN
IT WILL RISE DUE EAST.
THEN EACH SUCCESSIVE DAY IT WILL RISE A LITTLE
BIT FARTHER SOUTH OF EAST UNTIL ON THE FIRST
DAY OF WINTER WHEN IT WILL RISE AT ITS FARTHEST
POINT SOUTHEAST, AFTER WHICH IT WILL SLOWLY
START TO RETRACE ITS JOURNEY NORTH
ONCE AGAIN.
DEAN:
AND THIS ENTIRE CYCLE REPEATS YEAR AFTER YEAR
AFTER YEAR.
IN FACT, ALMOST ALL ANCIENT CULTURES KEPT
TRACK OF THIS RISING AND SETTING OF THE SUN
AT DIFFERENT PLACES ON THE HORIZON.
MAYBE THEY WOULD SET UP STONES TO MARK THE
SUNRISE AND
SUNSET POINTS.
JAMES:
OR POSTS.
OR MOUNDS.
OR WINDOWS.
OR EVEN BUILDINGS.
SORRY, DEAN.
NO EGGS.
DEAN:
AWW MAN!
JAMES:
WITH THESE MARKERS THEY COULD MEASURE THE
LENGTH OF YEAR AND CREATE THE FIRST CALENDARS.
DEAN:
SO PUT THOSE SUN VISORS DOWN AS YOU DRIVE
BACK AND FORTH TO WORK NEXT WEEK AND WHY NOT
START YOUR OWN PERSONAL RECORD -
KEEPING TRACK OF WHERE THE SUN RISES AND SETS
ON YOUR HORIZON THROUGHOUT THE YEAR.
JAMES:
STARTING NEXT WEEK, YOULL DEFINITELY NOTICE
THAT THE SUN WILL RISE AND SET FARTHER SOUTH
EACH DAY -
AND THAT MEANS WINTER IS ONLY A FEW
MONTHS AWAY.
AND DEAN, ONLY I CAN BALANCE AN EGG WHENEVER
I WISH!
DEAN:
NO WAY!
BOTH:
KEEP LOOKING UP!