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!