WPBT2's Star Gazers

Episode #14-24 "The Lost Jewel in the Northern Crown"
Air Dates June 16, 2014 - June 22, 2014



FIVE MINUTE EPISODE SCRIPT
DEAN: WELCOME TO STAR GAZERS. I'M DEAN REGAS, ASTRONOMER FROM THE CINCINNATI OBSERVATORY.

JAMES: AND I'M JAMES ALBURY, DIRECTOR OF THE KIKA SILVA PLA PLANETARIUM IN GAINESVILLE FLORIDA. THIS WEEK WE'RE GOING TO SHOW YOU ONE OF THE MOST EXQUISITE LITTLE CONSTELLATIONS IN THE SUMMER SKY.

DEAN: AND IT'S EASY TO FIND IF YOU HAVE FAIRLY DARK SKIES AND YOU'RE AWAY FROM CITY LIGHTS, AND USE OUR OLD 'ARC TO ARCTURUS' TRICK.

JAMES:  WHAT ARE WE TALKING ABOUT?  LET'S SHOW YOU!

JAMES: OKAY, WE'VE GOT OUR SKIES SET UP FOR THIS WEEK BETWEEN 9 AND 10 PM YOUR LOCAL TIME.  IF YOU LOOK TO THE NORTHWEST, YOU'LL FIND OUR OLD FRIEND THE BIG DIPPER. USING OUR OLD TRICK OF DRAWING AN IMAGINARY LINE FOLLOWING THE ARC OF THE DIPPER'S HANDLE, WE WILL ARC TO THE CLOSEST BRIGHT STAR, ARCTURUS. REMEMBER? ARC TO ARCTURUS?

DEAN:  THEN, INSTEAD OF CONTINUING THAT ARC TO SPEED ON TO SPICA IN THE CONSTELLATION VIRGO, WE'LL SIMPLY HANG A RIGHT AT ARCTURUS, AND THEN LOOK SLIGHTLY EAST OF IT FOR THE STAR ALPHECCA.  ALPHECCA IS NOT NEARLY AS BRIGHT AS ARCTURUS BUT IT'S THE BRIGHTEST STAR IN ITS PART OF THE SKY.

JAMES:  ALPHECCA IS THE BRIGHTEST STAR IN A HALF CIRCLE OF STARS WE CALL CORONA BOREALIS, THE NORTHERN CROWN.  AT THIS TIME OF YEAR, CORONA BOREALIS IS ALMOST DIRECTLY OVERHEAD BETWEEN 9 AND 10 PM. THE REASON ALPHECCA IS SO MUCH BRIGHTER THAN THE OTHER STARS IN THE CROWN IS BECAUSE IT IS SO MUCH CLOSER TO US. THIS STAR IS ONLY 75 LIGHT YEARS AWAY.

DEAN:  NOW, ALTHOUGH ALPHECCA IS A LOVELY STAR IN THE CROWN, THERE IS A FAR MORE INTERESTING ONE. IT IS CALLED T-CORONAE BOREALIS, OR MORE POPULARLY "BLAZE STAR". ALMOST 150 YEARS AGO SOMETHING VERY PECULIAR HAPPENED TO THIS STAR. MOST OF THE TIME, T-CORONAE BOREALIS IS SO DIM THAT IT CAN ONLY BE SEEN THROUGH A TELESCOPE. HOWEVER, JUST ONE YEAR AFTER THE END OF THE CIVIL WAR ON MAY 12, 1866 ASTRONOMERS SAW THIS STAR ERUPT INTO SUCH BLAZING BRILLIANCE THAT BY THE END OF THE NIGHT IT WAS ACTUALLY BRIGHTER THAN THE BRIGHTEST STAR IN THE CROWN, ALPHECCA.

JAMES:  AMAZED BY THIS INCREDIBLE OUTBURST, ASTRONOMERS CALCULATED THAT ITS LIGHT HAD INCREASED 2,500 TIMES. BY THE NEXT NIGHT IT HAD ALREADY BEGUN TO FADE AND JUST ONE WEEK LATER IT WAS ONCE AGAIN INVISIBLE TO THE NAKED EYE.

DEAN:  WHAT IN HEAVENS NAME HAPPENED TO IT? AND WOULD IT EVER BE SEEN AGAIN? WELL, THE ANSWER TO THAT QUESTION IS 'YES', BUT IT WOULDNT BE SEEN AGAIN BY THOSE WHO HAD ORIGINALLY WITNESSED IT. 80 YEARS LATER, ON FEBRUARY 9TH, 1946, T-CORONAE BOREALIS FLARED UP AGAIN. ALTHOUGH THE ASTRONOMERS OF 1946 DIDN'T UNDERSTAND THE COMPLETE PICTURE, THEY WERE ABLE TO DETERMINE THAT THE OUTER LAYERS OF THIS STAR HAD EXPLODED AND WERE EXPANDING AWAY FROM THE STAR AT A RATE OF OVER 2,700 MILES PER SECOND.

JAMES:  LATER STUDIES SHOWED THAT WHILE THE BRIGHTEST STAR IN THE CROWN, ALPHECCA, WAS ONLY 75 LIGHT YEARS AWAY, T-CORONAE BOREALIS WAS OVER 2600 LIGHT YEARS AWAY, WHICH MEANT, THAT FOR IT TO BECOME EVEN BRIGHTER THAN ALPHECCA, IT WOULD HAVE HAD TO HAVE BLAZED (IN JUST A FEW HOURS TIME) FROM ITS NORMAL 50 TIMES BRIGHTER THAN OUR SUN TO OVER 200 THOUSAND TIMES BRIGHTER THAN OUR SUN. SO, WHAT COULD CAUSE THIS?

DEAN:  WELL, ASTRONOMERS NOW KNOW THAT T-CORONAE BOREALIS IS ACTUALLY TWO STARS, A GIANT RED STAR WITH A BLUE -WHITE DWARF COMPANION.  AS THE STARS ORBIT EACH OTHER, GAS IS GRAVITATIONALLY EXCHANGED BETWEEN THE TWO.  EVERY SO OFTEN, THE SUPER HOT DWARF STAR REACHES A CRITICAL LEVEL OF GAS COLLECTED FROM THE COOL RED GIANT STAR.  ITS OUTER LAYERS OF GAS VIOLENTLY EXPLODE AND FLING THEIR MATERIAL THROUGHOUT THE HEAVENS, CAUSING THE DWARF STAR TO BECOME THOUSANDS OF TIMES BRIGHTER, IN JUST A FEW SECONDS.

JAMES:  AND THEN, AFTER THE GAS IS SHED, THE STAR QUICKLY DIMS BACK TO ITS NORMAL INVISIBLE-TO-THE-NAKED-EYE BRIGHTNESS AND THE WHOLE SLOW PROCESS OF ACCUMULATING GAS TO YET ANOTHER CRITICAL LEVEL BEGINS.  ASTRONOMERS CALL THIS A RECURRENT NOVA. SO, THE QUESTION IS, WILL THE LOST JEWEL IN THE CROWN, T-CORONAE BOREALIS, BRIGHTEN AGAIN IN OUR LIFETIME? WILL WE HAVE TO WAIT UNTIL 2026 TO SEE IT AGAIN?

DEAN:  WHO KNOWS? BUT ONE NIGHT, IF YOU'RE LUCKY, YOU MAY SEE THE LOST JEWEL OF THE NORTHERN CROWN, BLAZING AWAY IN ALL ITS BRILLIANCE.

JAMES:  FOR ONE BRIEF NIGHT…

DEAN:  AND ONE NIGHT ONLY, IF YOU SIMPLY REMEMBER TO…

BOTH: KEEP LOOKING UP!

 

Episode #14-24 "The Lost Jewel in the Northern Crown"
Air Dates June 16, 2014 - June 22, 2014



ONE MINUTE EPISODE SCRIPT
DEAN: THIS WEEK WE'RE GOING TO SHOW YOU ONE OF THE MOST EXQUISITE LITTLE CONSTELLATIONS IN THE SUMMER SKY

JAMES: AND IT HOLDS A SURPRISING SECRET. LET'S SHOW YOU!

JAMES: OKAY, WE'VE GOT OUR SKIES SET UP FOR THIS WEEK BETWEEN 9 AND 10 PM YOUR LOCAL TIME.  IF YOU LOOK ALMOST DIRECTLY OVERHEAD YOU'LL SEE A HALF CIRCLE OF STARS WE CALL CORONA BOREALIS, THE NORTHERN CROWN.  THE BRIGHTEST STAR OF CORONA BOREALIS IS ALPHECCA.

DEAN: HOWEVER, IN 1866 AND 1946, ASTRONOMERS SAW A STAR CALLED T-CORONAE BOREALIS ERUPT INTO SUCH BLAZING BRILLIANCE THAT BY THE END OF THE NIGHT IT WAS ACTUALLY BRIGHTER THAN ALPHECCA, THE BRIGHTEST STAR IN THE CROWN.  THIS IS CAUSED BY THE EXPLOSIVE DISCHARGE OF ACCUMULATED GAS EXCHANGED BETWEEN A RED GIANT AND ITS WHITE DWARF COMPANION.

JAMES: SO, WHO KNOWS? ONE NIGHT, IF YOU'RE LUCKY, YOU MAY SEE THE LOST JEWEL OF THE NORTHERN CROWN, BLAZING AWAY IN ALL ITS BRILLIANCE.

BOTH: KEEP LOOKING UP!

 

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