I'M JAMES ALBURY, DIRECTOR OF THE KIKA SILVA PLA PLANETARIUM IN GAINESVILLE, FLORIDA. AND I'M DEAN REGAS, ASTRONOMER FROM THE CINCINNATI OBSERVATORY.

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1 STAR GAZERS SG M APRIL 16-22, 2018 TIME TRAVELING WITH THE BIG DIPPER (UPDATE OF 1217) WELCOME TO STAR GAZERS. I'M JAMES ALBURY, DIRECTOR OF THE KIKA SILVA PLA PLANETARIUM IN GAINESVILLE, FLORIDA. AND I'M DEAN REGAS, ASTRONOMER FROM THE CINCINNATI OBSERVATORY. WE'RE HERE TO HELP YOU FIND YOUR WAY AROUND THE SKY. THE BIG DIPPER IS ONE OF THE EASIEST STAR PATTERNS TO FIND IN THE NIGHT SKY. THE BIG DIPPER IS IN A GREAT LOCATION FOR VIEWING THIS MONTH, AND I ALWAYS LOVE FINDING IT. IT MAKES ME THINK OF THE ASTRONOMICALLY VAST DISTANCES FROM EARTH TO STARS. EXACTLY. ONE OF THE GREATEST THINGS ABOUT THE BIG DIPPER IS THAT THE STARS ARE AT JUST THE RIGHT DISTANCE FROM US THAT THE LIGHT WE SEE COMING FROM THEM TAKES A LIFETIME TO GET HERE. WHAT ARE WE TALKING ABOUT?

2 LET'S TRAVEL THROUGH SPACE AND TIME! (STOP & DROP) OK, WE HAVE OUR SKIES SET FOR JUST AFTER SUNSET NEXT WEEK, AND IF YOU LOOK TOWARD THE NORTH YOU'LL SEE THE SEVEN BRIGHT STARS THAT MAKE UP THE BIG DIPPER. WHEN YOU CONNECT THE FOUR STARS TO MAKE A SPOON AND THE THREE OTHER STARS FOR A HANDLE, YOU CAN EASILY IMAGINE THIS GIANT SPOON AMONG THE STARS. THE BIG DIPPER STARS ARE SO INCREDIBLY FAR AWAY THAT WE HAVE TO MEASURE THEIR DISTANCE WITH A SPECIAL TERM, A MEASURE OF DISTANCE THAT WE CALL A LIGHT YEAR. A LIGHT YEAR IS SIMPLY HOW FAR LIGHT TRAVELS IN ONE YEAR, WHICH IS A DISTANCE OF APPROXIMATELY SIX TRILLION MILES; WHICH FURTHER MEANS THAT IF THERE WAS A STAR SIX TRILLION MILES AWAY FROM US, WE WOULD BE LOOKING AT THE STAR NOT AS IT EXISTS NOW, BUT AS IT EXISTED ONE YEAR AGO. SO WHEN YOU LOOK INTO SPACE, YOU RE ALSO LOOKING BACK IN TIME. WHOA, THAT S DEEP MAN. SO, WHEN WE SEE THE STARS OF THE BIG DIPPER WE CAN DO SOME TIME TRAVELING.

3 TAKE THE DIMMEST STAR IN THE BIG DIPPER, NAMED MEGREZ FOR EXAMPLE. MEGREZ IS 58 LIGHT-YEARS AWAY; WHICH MEANS THAT WHEN WE LOOK AT MEGREZ, WE SEE IT AS IT ACTUALLY EXITED 58 YEARS AGO - IN THAT WAS THE YEAR DAVID DUCHOVNY (AGENT MULDER FROM THE TV SHOW X-FILES) WAS BORN. ALIOTH, THE FIRST STAR IN THE HANDLE OF THE BIG DIPPER AND PHECDA, A STAR AT THE BASE OF THE SPOON ARE BOTH ABOUT 83 LIGHT YEARS AWAY. SO WHEN WE LOOK AT ALIOTH AND PHECDA TONIGHT, WE SEE THE LIGHT THAT LEFT THOSE STARS IN 1935, THREE YEARS BEFORE OUR FAVORITE STAR GAZER, JACK HORKHEIMER WAS BORN. MIZAR, THE STAR AT THE BEND OF THE BIG DIPPER S HANDLE IS 78 LIGHT YEARS AWAY; WHICH MEANS THAT WHEN WE LOOK AT MIZAR, WE SEE IT AS IT ACTUALLY EXISTED 78 YEARS AGO, IN THE SAME YEAR THAT PATRICK STEWART (STAR TREK CAPTAIN JEAN-LUC PICARD) WAS BORN. INDEED, AND THAT'S NOT ALL. THE LAST STAR IN THE HANDLE, ALKAID IS SO FAR AWAY, THAT THE LIGHT THAT LEFT IT BEGAN ITS JOURNEY 104 YEARS AGO IN 1914, THE SAME YEAR THE PANAMA CANAL OPENED.

4 THE LAST TWO STARS ARE THE POINTER STARS, MERAK AND DUBHE. IF YOU CONNECT A LINE FROM MERAK TO DUBHE AND KEEP GOING, IT WILL POINT YOU TO THE NORTH STAR. MERAK IS 80 LIGHT YEARS FROM EARTH, BUT DUBHE, THE ONE CLOSER TO THE NORTH STAR IS A WHOPPING 123 LIGHT YEARS FROM US. YEP! THE LIGHT YOU SEE FROM DUBHE LEFT IT IN AND WHAT HAPPENED IN 1895 YOU MIGHT ASK? KATHARINE LEE BATES WROTE THE SONG, AMERICA THE BEAUTIFUL LOOKING AT THE STARS OF THE BIG DIPPER CAN REALLY MAKE YOU FEEL LIKE A TIME TRAVELER. SO IN 2053, WE'LL GET TO SEE THE LIGHT THAT LEFT MIZAR THE YEAR I WAS BORN. AND BY MY CALCULATIONS JAMES, YOU'LL BE WHAT 86 THAT YEAR? YEP! I'LL BE GETTING READY FOR HALLEY'S COMET TO RETURN IN ABOUT 8 MORE YEARS. YEAH THE YEAR 2061 WILL BE HERE IN NO TIME - COSMICALLY SPEAKING! CLOSE-UP ENDING

5 SO, NEXT TIME YOU LOOK UP AT THE BIG DIPPER REMIND YOURSELF, IF YOU'RE STILL YOUNG, THAT SOME DAY YOU WILL SEE THESE STARS AS THEY ACTUALLY EXISTED WHEN YOU FIRST APPEARED ON THIS PLANET. AND IF YOU'RE NOT SO YOUNG, DELIGHT IN THE THOUGHT THAT YOU ARE LOOKING BACK AT SOME OF THE FEW THINGS THAT APPEAR EXACTLY AS THEY WERE IN THOSE SUNLIT DAYS AND STAR-FILLED NIGHTS OF YOUTH. HAPPY STAR GAZING AND HAPPY TIME TRAVELING! BOTH: KEEP LOOKING UP! ****************