THE SUPER SPRING TRIANGLE
JAMES: HEY THERE STAR GAZERS, I’M JAMES ALBURY, DIRECTOR OF THE KIKA SILVA PLA PLANETARIUM
IN GAINESVILLE, FLORIDA.
DEAN: AND I’M DEAN REGAS, ASTRONOMER FOR THE CINCINNATI OBSERVATORY.
WE’RE HERE TO HELP YOU FIND YOU WAY AROUND THE SKY TONIGHT.
IT’S THE MIDDLE OF SPRING AND THREE BRIGHT STARS ARE TAKING CENTER STAGE.
JAMES: IT’S CALLED THE SPRING TRIANGLE AND IT’S HUGE!
COVERING ONE-SIXTH OF THE SKY, THE SPRING TRIANGLE INCORPORATES THREE ANCIENT CONSTELLATIONS.
THERE’S A LION, A HERDSMAN, AND A MAIDEN UP THERE.
DEAN: NOW, I’LL BE HONEST.
IT’S REALLY TOUGH TO SEE A LION, A HERDSMAN, AND A MAIDEN IN THOSE STARS.
BUT EVEN THOUGH I DON’T HAVE THE REQUIRED IMAGINATION…
JAMES: I DON’T KNOW IF ANYONE DOES…
DEAN: THE THREE STARS ARE EASY TO FIND.
JAMES: AND AT LEAST YOU’LL KNOW WHERE THESE CONSTELLATIONS LIVE.
DEAN: WHAT ARE WE TALKING ABOUT?
LET’S SHOW YOU.
DEAN: OKAY, WE’RE FACING SOUTHEAST AT 10PM ANY NIGHT THIS WEEK.
WE HAVE THE SUPER-WIDE-ANGLE VIEW ON, SINCE THE SPRING TRIANGLE IS HUGE.
JAMES: IF YOU LIVE IN A CITY, THE THREE STARS IN THE SPRING TRIANGLE MIGHT BE ALL YOU CAN
SEE. AND THERE THEY ARE, 1, 2, AND 3.
DEAN: WE’LL START WITH THE STAR ON THE FAR RIGHT.
THAT’S REGULUS, THE BRIGHTEST STAR IN THE CONSTELLATION OF LEO THE LION.
YOU USUALLY START SEEING REGULUS EARLY IN THE SPRING AND IT SHINES WITH A BLUE-WHITE
LIGHT.
JAMES: THE STAR FARTHEST TO THE LEFT, AND THE BRIGHTEST OF THE TRIO IS ARCTURUS.
ARCTURUS IS THE BRIGHTEST STAR IN THE HERDSMAN NAMED BOOTES.
IF YOU LOOK CAREFULLY, YOU’LL NOTICE THAT ARCTURUS IS QUITE ORANGE - A VERY DIFFERENT
COLOR THAN REGULUS.
DEAN: AND THE THIRD STAR IN THE SPRING TRIANGLE IS SPICA, THE BRIGHTEST STAR IN VIRGO THE
MAIDEN.
SPICA IS THE DIMMEST OF THE THREE AND THE BLUEST TOO.
JAMES: LET’S COMPARE THE THREE STARS IN THE SPRING TRIANGLE TO OUR SUN.
THE SUN IS ABOUT 865,000 MILES IN DIAMETER AND LIES ABOUT 93 MILLION MILES AWAY.
THAT’S THE DISTANCE LIGHT TRAVELS IN 8 MINUTES.
SO WE’D SAY THAT THE SUN IS 8 LIGHT MINUTES AWAY.
DEAN: THE SUN IS DINKY COMPARED TO THE THREE SPRING TRIANGLE STARS.
REGULUS, FOR EXAMPLE, IS THREE TIMES THE DIAMETER OF THE SUN, SHINES 288 TIMES BRIGHTER AND
IS 79 LIGHT YEARS AWAY.
SO INSTEAD OF 93 MILLION MILES, REGULUS MORE THAN 460 TRILLION MILES AWAY.
JAMES: YIKES!
SPICA IS EVEN BIGGER AT 7.5 TIMES THE DIAMETER OF OUR SUN, SHINES TWENTY-TWO HUNDRED TIMES
BRIGHTER AND LIES 250 LIGHT YEARS AWAY.
THAT’S EQUAL TO ABOUT 1.5 QUADRILLION MILES!
DEAN: AND THAT LEAVES ARCTURUS.
IT IS BY FAR THE LARGEST OF THESE STARS AT 25 TIMES THE SUN’S DIAMETER.
SINCE IT IS AN ORANGE STAR, IT’S NOT AS HOT AS THE OTHERS.
SO WHILE IT STILL SHINES 170 TIMES BRIGHTER THAN OUR SUN, IT DOESN’T GIVE OFF NEARLY
AS MUCH ENERGY AS THE HOTTER REGULUS AND SPICA.
JAMES: ARCTURUS IS THE CLOSEST OF THE THREE SPRING TRIANGLE STARS AT AROUND 37 LIGHT YEARS.
BUT THAT’S STILL LIKE 217 TRILLION MILES.
DEAN: BUT WHO’S COUNTING?
DEAN: WE’RE ZOOMED IN ON REGULUS AND ITS CONSTELLATION LEO.
WHEN I CONNECT THE DOTS ON THE MAIN STARS, I GUESS I CAN SEE A LION SITTING WITH HIS
FRONT PAWS STRETCHED OUT.
WELL, IT’S CERTAINLY EASIER TO IMAGINE THAN A HERDSMAN OR A MAIDEN - JUST YOU WAIT AND
SEE.
THE LION HAS A BACKWARD QUESTION MARK FOR A HEAD ABOVE REGULUS, AND A TRIANGLE FOR A
TAIL.
AND THIS IS SUPPOSED TO BE THE NEMEAN LION THAT WAS KILLED BY HERCULES.
WHEW, THAT MUST’VE BEEN SOME BATTLE!
JAMES: NOW WE’RE LOOKING AT THE STAR ARCTURUS AND ITS CONSTELLATION OF BOOTES.
DEAN’S RIGHT, I CAN’T SEE A HERDSMAN IN THESE STARS AT ALL.
INSTEAD, I LOOK FOR STARS THAT MAKE A KITE-SHAPE OR AN ICE CREAM CONE.
THEN, DOWN AND TO THE RIGHT OF BOOTES, YOU CAN FIND SPICA AND THE STARS OF VIRGO THE
MAIDEN.
SHE IS OFTEN DEPICTED AS A GODDESS LYING ON HER SIDE HOLDING A PIECE OF WHEAT, THE STAR
SPICA.
IF YOU CAN SEE A HERDSMAN AND A MAIDEN IN THESE STARS, CONGRATULATIONS, YOU HAVE AN
ANCIENT GREEK IMAGINATION!
DEAN: SO THERE YOU HAVE IT, THE THREE BRIGHTEST STARS IN THE SPRING SKY MAKING A HUMONGOUS
TRIANGLE COVERING 1/6 OF THE HEAVENS.
REGULUS, ARCTURUS, AND SPICA.
JAMES: AND ALTHOUGH YOU MAY HAVE TROUBLE SEEING LEO THE LION AROUND REGULUS…
DEAN: BOOTES THE HERDMAN AROUND ARCTURUS…
JAMES: OR VIRGO THE MAIDEN AROUND SPICA, YOU CAN APPRECIATE THESE THREE CELESTIAL BEACONS
FOR WHAT THEY ARE: FASCINATING AND FAR-FLUNG STARS.
IT’S ALL THERE WHEN YOU…
BOTH: .KEEP LOOKING UP!