♪
>> Frank: THE CERRO TOLOLO
INTERNATIONAL OBSERVATORY SITS
ATOP A MOUNTAIN IN CHILE.
IT'S IN THE ANDES MOUNTAINS,
AND IT'S ONE OF THE BEST-KNOWN
OBSERVATORIES IN THE WORLD
BECAUSE OF THE ALTITUDE.
THE AIR IS CLEAR, AND THERE
IS NO LIGHT POLLUTION.
HOWEVER, ASTRONOMERS DON'T LOOK
THROUGH THESE TELESCOPES.
SENSITIVE CAMERAS AND
COMPUTERS DO THE LOOKING.
ASTRONOMERS ANALYZE
WHAT WAS FOUND.
>> WHAT YOU DO INITIALLY IS,
YOU -- YOU HAVE YOUR
TARGET STAR.
YOU HAVE ITS COORDINATES.
YOU ENTER THOSE COORDINATES
INTO THE TRACKING SYSTEM.
THE TELESCOPE MOVES TO THAT
STAR'S LOCATION.
THEN YOU SET THE TELESCOPE
TO TRACK THAT STAR.
SO IT ALWAYS STAYS IN THAT
STAR'S FIELD OF VIEW.
AND THEN YOU SET IT TO TAKE
HOW MANY, UM, NUMBER OF IMAGES
YOU WANT TO TAKE OVER THE
NEXT COUPLE OF HOURS.
>> Frank: AND THE TEAM FROM
HIGH POINT UNIVERSITY WAS
LOOKING FOR SOMETHING REALLY
RARE -- A PULSATING STAR.
>> SO SOME STARS, IN ESSENCE,
ACT LIKE MUSICAL INSTRUMENTS.
THEY PULSATE.
THEY VIBRATE FOR VARIOUS
REASONS DUE TO THEIR
ATMOSPHERIC COMPOSITION.
AND AS THEY GET LARGER
AND SMALLER, THEIR
TEMPERATURE CHANGES.
THEIR DENSITY CHANGES.
AND YOU GET BRIGHTNESS
VARIATIONS.
>> Frank: THINK OF IT THIS WAY.
THIS IS SUNNY STAR.
SUNNY STAR IS ABOUT THE SIZE
OF OUR SUN, AND PULSATING STARS
LIKE SUNNY ARE ALMOST 10
BILLION YEARS OLD.
THEY'VE BURNED OFF MOST
OF THEIR FUEL.
THEY'VE STARTED TO COLLAPSE
AND TURN INTO A NEUTRON STAR.
AND SUNNY HAS JUST THE RIGHT
CONDITIONS TO PULSATE.
IF YOU'RE AN ASTRONOMER LOOKING
AT SUNNY, YOU CAN TELL A LOT
ABOUT WHAT SUNNY IS MADE OF
BY STUDYING HOW THAT ENERGY
TRAVELS THROUGH THE STAR'S
ATMOSPHERE AND THROUGH THE
STAR ITSELF.
>> YOU CAN ALMOST THINK OF
PULSATING STARS AS STAR QUAKE
TYPE OBJECTS.
JUST AS EARTHQUAKE WAVES
PROPAGATE THROUGH CERTAIN PARTS
OF THE EARTH, THESE WAVES WILL
PROPAGATE ACROSS THE ATMOSPHERES
OF THESE STARS, PRODUCING THESE
BRIGHTNESS VARIATIONS.
AND JUST LIKE GEOLOGISTS CAN
INFER THE INTERIOR STRUCTURE
OF THE EARTH FROM STUDYING
THE WAY EARTHQUAKE WAVES
PROPAGATE THROUGH THE EARTH,
WE CAN ALSO SEE INSIDE STARS
BY MONITORING THEIR PULSATIONS.
>> Frank: IN SHORT, STUDY HOW
THE WAVES TRAVEL THROUGH THE
STAR, AND YOU'LL KNOW WHAT KIND
OF STAR STUFF THAT STAR
IS MADE OF.
>> WE ARE GOING TO THE CENTER
OF WHITE DWARF STARS, WHICH ARE
ESSENTIALLY THE FUTURE OF
STARS LIKE THE SUN.
SO WE'RE LEARNING ABOUT WHAT
THEIR INTERIOR COMPOSITION IS
MADE OF, WHAT THOSE
COMPOSITIONAL GRADIENTS ARE MADE
OF, HOW MUCH CERTAIN ELEMENTS
THERE ARE IN DIFFERENT LAYERS
OF THE STAR JUST BY WATCHING ITS
BRIGHTNESS CHANGE ON VERY SHORT
TIME SCALES.
>> Frank: THE TEAM HAD A TARGET
LIST OF STARS TO STUDY,
OBJECTS WITH JUST THE RIGHT
SIZE AND OTHER CHARACTERISTICS
TO MAKE THEM CANDIDATES
TO BE PULSATING STARS.
>> SO THIS IS WHAT WE
SAW RIGHT THERE.
SO THIS IS THE TARGET STAR.
>> Frank: THAT'S THE STAR.
>> THAT'S THE STAR RIGHT THERE.
AND THEN JUST NOW, WE WERE USING
THIS STAR AS A COMPARISON.
>> Frank: YEAH, THE STAR
ISN'T MUCH TO LOOK AT.
AN OBJECT 2,000 OR 3,000
LIGHT-YEARS AWAY IS DIFFICULT
TO SEE VERY WELL.
BUT THEN THE TEAM STUDIED THE
LIGHT ENERGY COMING
FROM THE STAR.
>> BASICALLY, IN ORDER TO KNOW
THAT YOU HAVE A PULSATING STAR,
YOU -- YOU LOOK AT A GRAPH
THAT LOOKS LIKE THIS.
AND WHAT YOU'RE
LOOKING FOR IS SPIKES.
SO THESE TWO SPIKES RIGHT HERE
TELL YOU THAT YOU HAVE
PULSATIONS, RIGHT?
BUT IT'S NOT GOOD ENOUGH TO SEE
THESE SPIKES ON ONE NIGHT.
YOU WOULD NEED TO BE ABLE TO SEE
THEM REPETITIVELY.
SO WHAT WE DO IS, WE WENT BACK
ON A DIFFERENT NIGHT.
AND WE DID THE SAME PROCESS,
SAME EVERYTHING.
AND WE SAW THESE
TWO PULSES AGAIN.
SO IF YOU KIND OF FLIP THROUGH
THEM, HERE'S THE TWO PULSES.
YOU GO THE NEXT NIGHT.
THIS IS A COMPLETELY NEW NIGHT,
COMPLETE NEW OBSERVATIONS,
AND YOU SEE THESE TWO PULSES,
WHICH INDICATE TO US THAT WE
HAVE A PULSATING STAR, BECAUSE
YOU WERE ABLE TO REPLICATE THE
DATA.
>> Frank: THE PATTERN
CONFIRMED THE DISCOVERY.
AND FURTHER ANALYSIS DETERMINED
THE TARGET PULSATING STAR WAS
ORBITING ANOTHER MUCH
SMALLER NEUTRON STAR.
AND THAT DOUBLE NEUTRON STAR
SYSTEM IS INCREDIBLY RARE.
TO DATE, ONLY 12 IN THE ENTIRE
UNIVERSE HAVE BEEN FOUND.
>> I MEAN, IT WAS REALLY COOL
TO SEE, YOU KNOW, ALL THIS CODE
THAT WE WROTE AND STAYING UP ALL
NIGHT, DOING OBSERVATIONS,
AND TO KIND OF SEE THE OUTCOME
BE A -- YOU KNOW, A NEW
DISCOVERY THAT ONLY MYSELF,
MY PROFESSOR, AND ANOTHER
STUDENT, YOU KNOW -- WE WERE THE
ONLY PEOPLE THAT KNEW ABOUT THIS
AT THE TIME.
SO, YOU KNOW, YOU KIND OF DON'T
REALLY KNOW HOW TO REACT AT
FIRST, SO YOU HAVE TO
TAKE -- TAKE IT IN.
>> MY RULE WITH
STUDENTS IS THIS.
IF THEY FIND SOMETHING NEW,
LIKE A PULSATING STAR, THEY ARE
NOT ALLOWED TO TELL ME OR ANYONE
ELSE FOR 20 MINUTES.
WHY?
FOR THOSE 20 MINUTES, THEY MIGHT
BE THE ONLY PEOPLE IN THE
HISTORY OF HUMANITY TO KNOW THIS
ONE PIECE OF INFORMATION.
AND THAT IS A COOL FEELING I
CAN'T EVEN DESCRIBE TO PEOPLE
UNLESS YOU'VE EXPERIENCED
IT YOURSELF.
