JAMES: WELCOME TO STAR GAZERS.
I'M JAMES ALBURY, DIRECTOR OF THE KIKA SILVA PLA PLANETARIUM IN GAINESVILLE FLORIDA.
DEAN: AND I'M DEAN REGAS, ASTRONOMER FROM THE CINCINNATI OBSERVATORY AND WE'RE HERE
TO HELP YOU FIND YOUR WAY AROUND THE SKY TONIGHT.
JAMES: DEAN AND I ARE REALLY EXCITED BECAUSE LAST WEEK, ONE OF OUR FAVORITE PLANETS WAS
AT OPPOSITION AND AS A RESULT, IT'S NOW IN A GREAT SPOT IN THE SKY AND WE CAN VIEW IT
ALL NIGHT LONG.
DEAN: AND THAT PLANET IS THE EVER POPULAR AND LOVELY, RINGED PLANET, SATURN!
JAMES: LET'S SHOW YOU!
DEAN: OK, LET'S FIRST EXPLAIN A LITTLE BIT ABOUT WHAT OPPOSITION MEANS.
IF WE COULD VIEW OUR SOLAR SYSTEM FROM HIGH ABOVE THE NORTH POLE OF OUR SUN, AS WE LOOK
DOWN, WE CAN SEE EARTH'S ORBIT AND SATURN'S ORBIT AROUND THE SUN.
EARTH IS ABOUT 93 MILLION MILES AWAY FROM THE SUN AND IT TAKES 365 1/4 DAYS FOR EARTH
TO MAKE ONE TRIP AROUND THE SUN.
IN LAYMAN'S TERMS, WE REFER TO THAT AS A YEAR.
JAMES: SATURN IS THE 6TH PLANET FROM THE SUN AND IS ALMOST 900 MILLION MILES AWAY.
IT MOVES MUCH SLOWER IN ITS ORBIT AND IT TAKES ALMOST 30 EARTH YEARS TO MAKE ONE TRIP AROUND
THE SUN.
THEREFORE, EARTH MAKES 30 TRIPS AROUND THE SUN FOR EVERY ONE TRIP OF SATURN.
SO IT'S QUITE OBVIOUS THAT EARTH AND SATURN ARE CONSTANTLY CHANGING THEIR POSITION IN
SPACE WITH RESPECT TO ONE ANOTHER.
DEAN: WHEN SATURN IS AT ITS GREATEST DISTANCE FROM EARTH, IT IS ON THE OTHER SIDE OF THE
SUN AS SEEN FROM EARTH AND THAT IS CALLED SUPERIOR CONJUNCTION; WHICH HAPPENED LAST
YEAR ON DECEMBER 10TH.
ON THAT DAY, SATURN WAS A WHOPPING ONE BILLION MILES AWAY FROM US.
BUT 6 MONTHS LATER, ON THURSDAY, JUNE 15TH, EARTH AND SATURN WERE LINED UP WITH THE SUN.
SATURN IS NOW ON THE SAME SIDE OF THE SUN AS THE EARTH AND IS A LOT CLOSER.
JAMES: OR, IF YOU THINK OF IT FROM OUR PERSPECTIVE, THE EARTH IS IN THE MIDDLE AND SATURN WILL
BE ON THE OPPOSITE SIDE OF THE SKY WITH RESPECT TO THE SUN.
THIS ORIENTATION OF THE SUN, THE EARTH AND A PLANET IS CALLED OPPOSITION.
AND WHENEVER A PLANET IS AT OPPOSITION, IT IS ALWAYS AT ITS CLOSEST AND BRIGHTEST.
SO THIS WEEK, SATURN WILL BE JUST OVER 818 MILLION MILES AWAY, WHICH IS ALMOST 200 MILLION
MILES CLOSER THAN IT WAS ON DECEMBER 10TH, 2016!
AND ALTHOUGH SATURN IS ALWAYS CLOSE TO EARTH AND VERY BRIGHT EVERY OPPOSITION, THIS OPPOSITION
IS GOING TO LOOK GREAT BECAUSE OF THE WAY THE RINGS ARE TILTED TOWARD US.
DEAN: YOU SEE, EVEN THOUGH SATURN'S RINGS ARE ALWAYS TILTED AT THE SAME ANGLE WITH RESPECT
TO ITS ORBIT, IT'S RINGS SEEM TO TILT BACK AND FORTH AS SEEN FROM EARTH BECAUSE EARTH
CONSTANTLY CHANGES ITS POSITION IN RELATION TO SATURN, DURING SATURN'S 30 YEAR ORBIT.
FOR INSTANCE BACK IN JANUARY 2003, SATURN WAS IN SUCH A POSITION THAT ITS RINGS WERE
TILTED UP TO THE MAXIMUM WITH THE SOUTHERN SIDE OF THE RINGS WIDE OPEN - WHICH MEANS
THAT MORE SUNLIGHT REFLECTED OFF THE RINGS AND MADE THE PLANET MUCH BRIGHTER THAN USUAL.
AND THE RINGS LOOKED THEIR MOST DRAMATIC.
JAMES: THEN AS YEAR AFTER YEAR WENT BY, WE GRADUALLY SAW LESS AND LESS OF THE SOUTHERN
FACE OF SATURN'S RINGS, THEY SLOWLY CLOSED, SO TO SPEAK, AND BY JANUARY 2009 WE ACTUALLY
FACED SATURN'S RINGS EDGE-ON, AND FOR A FEW NIGHTS, THEY SEEMED TO DISAPPEAR.
HOWEVER AS THE YEARS HAVE PASSED, WE ARE NOW POSITIONED SO THAT WE CAN SEE THE NORTHERN
HEMISPHERE AND NORTHERN SIDE OF SATURN'S RINGS, MAKING SATURN APPEAR BRIGHTER IN THE SKY.
JAMES: SO CHECK OUT SATURN THIS WEEK AND IF YOU LOOK AT IT THROUGH EVEN THE SMALLEST TELESCOPE,
TRUST ME YOU'LL BE BLOWN AWAY.
TO FIND SATURN SIMPLY LOOK SOUTHEAST SHORTLY AFTER SUNSET.
IT WILL BE IN THE CONSTELLATION OPHIUCUS, JUST TO LEFT OF THE STARS OF SCORPIUS THE
SCORPION.
DEAN: AND WHILE YOU'RE LOOKING AT SATURN, PONDER THIS LITTLE BIT OF TRIVIA.
OF ALL THE PLANETS IN THE SOLAR SYSTEM, SATURN HAS THE LEAST DENSITY.
THIS MEANS THAT FOR AS BIG AS SATURN IS, IT'S NOT AS HEAVY AS YOU MIGHT THINK.
ITS DENSITY IS SO LOW THAT YOU COULD ACTUALLY FLOAT SATURN IN A BATH TUB FULL OF WATER;
IF YOU HAD A BATH TUB BIG ENOUGH.
JAMES: HMMM...SATURN IN A BATH TUB?
I WONDER IF SATURN WOULD LEAVE A RING.
DEAN: UGH!
ON THAT NOTE, HAPPY SATURN WATCHING, AND…
BOTH: KEEP LOOKING UP!