Original subtitles

Narrator: NASA's MISSION IS TO EXPLORE THE UNKNOWN.

Teitel: WHAT WE KNOW ABOUT THE UNIVERSE

IS A TINY FRACTION OF WHAT'S ACTUALLY OUT THERE.

Narrator: IN THE SEARCH FOR ANSWERS,

IT LAUNCHES ITS SCIENTISTS INTO SPACE,

ITS CRAFT BEYOND THE LIMITS OF THE SOLAR SYSTEM.

Lee: WE HAVE NO IDEA WHAT'S OUT THERE.

THERE MIGHT BE DANGERS LURKING IN THE DARKNESS.

WE RUN ACROSS MORE MYSTERIES THAN DISCOVERIES.

WE DON'T KNOW WHAT IT'S GONNA THROW AT US NEXT.

Narrator: A DEADLY GAS LEAK ON BOARD THE I.S.S...

IT COULD BE THE SMELL OF DEATH.

Narrator:...STRANGE STREAKS ON THE SURFACE OF MARS

THAT HINT AT SOMETHING INCREDIBLE...

McKay: THERE MIGHT BE LIFE ON MARS,

AND WE'RE JUST LOOKING IN THE WRONG PLACE.

Narrator: ...AND IS SOMEONE SEEDING CHEMTRAILS

INTO OUR ATMOSPHERE?

Jeras: SOME PEOPLE BELIEVE

THAT THERE'S A SINISTER PLOT GOING ON

THAT THEY'RE ACTUALLY SPRAYING CHEMICALS IN THE SKY.

Narrator: THESE ARE NASA's UNEXPLAINED FILES.

--Captions by VITAC-- www.vitac.com

CAPTIONS PAID FOR BY DISCOVERY COMMUNICATIONS

A SOVIET SPACECRAFT LANDS ON THE MOON.

THE SPACE RACE IS ON.

AND THE MOON IS THE NEXT BIG PRIZE.

Narrator: IT SENDS BACK PICTURES

AS PROOF OF ITS INCREDIBLE ACHIEVEMENT.

THESE ARE THE FIRST PICTURES FROM THE SURFACE OF THE MOON.

Narrator: BUT THE RUSSIANS ARE ABOUT TO GET SCOOPED.

Nichols: THIS WOULD BE LIKE

NEIL ARMSTRONG'S FIRST WORDS FROM THE MOON

BEING BROADCAST OVER RADIO MOSCOW.

Narrator: 1966.

THE UNITED STATES AND RUSSIA

ARE LOCKED IN A GLOBAL STRUGGLE FOR HEARTS AND MINDS.

WHILE THE WORLD WORRIES ABOUT THE GROWING NUCLEAR THREAT,

PROPAGANDA IS AN INCREASINGLY POTENT WEAPON.

AND NOTHING BETTER CAPTURES THE WORLD'S ATTENTION

THAN SUCCESS IN SPACE.

[ INDISTINCT RADIO CHATTER ]

BY THIS POINT IN THE MID-1960s,

THE SPACE RACE IS ESSENTIALLY A TIE.

BOTH SIDES HAVE HAD GREAT ACHIEVEMENTS.

BUT EACH SIDE IS STILL LOOKING FOR THAT ONE MORE STEP

THAT'S GOING TO GIVE THEM THE EDGE.

THE SPACE RACE IS ON.

AND THE MOON IS THE NEXT BIG PRIZE.

Schultz: WE'RE RACING AGAINST THE SOVIETS.

WHO'S GONNA DEMONSTRATE

THAT THEY CAN GET THERE FIRST AND ACTUALLY CAN LAND?

Narrator: IN JANUARY 1966,

THE RUSSIANS LAUNCH AN UNMANNED SPACECRAFT

CALLED LUNA 9.

U.S. INTELLIGENCE IS DESPERATE TO DISCOVER ITS MISSION.

THE SOVIETS ONLY RELEASE

INFORMATION ABOUT THEIR SPACE PROGRAM

THAT'S TO THEIR ADVANTAGE.

THEY ONLY TELL US WHAT THEY WANT US TO KNOW.

Narrator: THE U.S. ACTIVATES A GLOBAL NETWORK OF ASTRONOMERS

TO TRACK THE SMALL SPACECRAFT.

THE CENTRAL INTELLIGENCE AGENCY

IS UTILIZING RADIO TELESCOPES FROM ALL OVER THE WORLD

TO ESSENTIALLY EAVESDROP ON THE SOVIET SPACE PROGRAM.

BASICALLY, A LOT OF THE WORLD'S TOP ASTRONOMERS

ARE ACTING AS SPIES FOR THE C.I.A.

Nichols: THEY'RE KIND OF OUTSOURCING IT TO THEIR ALLIES

INCLUDING TO THE FOLKS AT JODRELL BANK IN THE U.K.

WHO RUN THE LARGEST RADIO TELESCOPE IN THE WORLD.

Narrator: THE AMERICANS' WORST FEARS ARE CONFIRMED

WHEN A LISTENING STATION IN ERITREA

CAPTURES LUNA 9'S TELEMETRY DATA.

IT'S ON COURSE TO TOUCH DOWN ON THE MOON.

Nichols; THIS IS GOING TO BE A BIG DEAL FOR ANY SPACE PROGRAM

BECAUSE FOR THE FIRST TIME,

A MAN-MADE OBJECT IS GOING TO BE ABLE

TO ENGAGE IN A CONTROLLED DESCENT

AND ACTUALLY LAND ON THE SURFACE OF THE MOON

INSTEAD OF CRASHING ON IT.

Narrator: PROBES, LIKE THE AMERICAN RANGER PROGRAM,

HAVE PREVIOUSLY REACHED THE MOON,

BUT ONLY BY CRASHING INTO IT.

Ferreira: IT'S TOTALLY DIFFERENT

TO SOFT LAND AND THEN TRANSMIT PICTURES

ACTIVELY FROM THE SURFACE OF THE MOON.

Narrator: IF THE RUSSIANS CAN PROVE

THAT THEY HAVE SOFT-LANDED ON THE MOON,

IT WOULD BE THE BIGGEST PROPAGANDA VICTORY

SINCE YURI GAGARIN BECAME THE FIRST MAN IN SPACE.

Nichols: THIS IS HOW THE SOVIETS ARE GONNA GET BACK ON TOP,

NOT JUST IN THE SPACE RACE, BUT IN THE COLD WAR ITSELF.

Narrator: IN THE U.K.,

JODRELL BANKS ASTRONOMERS LISTEN INTENTLY

TO THE STREAM OF DATA COMING FROM LUNA 9.

BUT AS IT HURDLES TOWARDS THE MOON,

SUDDENLY, THE STREAM VANISHES.

THE SIGNAL FROM LUNA 9 GOES DEAD.

WHAT'S HAPPENED? HAS IT CRASHED?

Narrator: THE ASTRONOMERS-TURNED-SPIES HOLD TIGHT.

AFTER FOUR MINUTES OF SILENCE, THERE IS STILL NO SIGNAL.

SOVIET LUNA PROBES DON'T HAVE A GREAT RECORD.

SOME OF THEM MISSED THE MOON ENTIRELY.

SO WHEN LUNA 9 GOES SILENT,

IT'S A GOOD ASSUMPTION THAT IT MAY HAVE CRASHED.

ACTUALLY, IT'S JUST TAKING A PAUSE

TO START SENDING A DIFFERENT SIGNAL.

Orwoll: THE SIGNAL COMES BACK.

LUNA 9 IS ALIVE.

BUT THE TRANSMISSION MODE HAS SHIFTED.

Narrator: AS AN ALIEN BURST OF SOUND

ECHOES AROUND THE JODRELL BANK OBSERVATORY,

THE TEAM OF ASTRONOMERS FRANTICALLY TRY

TO DECIPHER THE UNFAMILIAR TRANSMISSION.

THE PROBE MUST BE SENDING

SOME KIND OF MESSAGE BACK TO EARTH.

BUT THE QUESTION IS, WHAT IS IT?

Narrator: ONE OF THE ASTRONOMERS RECOGNIZES THE UNUSUAL SIGNAL.

THE TINY SPACECRAFT IS SENDING A FAX.

Orwoll: A BRITISH SCIENTIST SPYING FOR THE C.I.A.

IS LISTENING TO A SOVIET PROBE

SENDING A FAX SIGNAL FROM THE MOON.

Narrator: THIS IS LONG BEFORE THE DIGITAL REVOLUTION.

FAX MACHINES ARE EXTREMELY RARE.

THE SCIENTISTS GET ON THE PHONE

SEARCHING FOR A FAX MACHINE THEY CAN USE

TO DECIPHER THE SIGNAL.

ONE OF THEM CONTACTS A POPULAR BRITISH NEWSPAPER

CALLED THE DAILY EXPRESS.

THEY HAVE A FAX.

SENSING A SCOOP,

THE PAPER RUSHES IT OVER TO THE OBSERVATORY.

AND BRITAIN'S MOST SOPHISTICATED TELESCOPE

PLUGS INTO A FAX MACHINE.

THE SECONDS TICK BY

AS ASTRONOMERS AND JOURNALISTS WAIT TO SEE

WHAT DATA THE SOVIET CRAFT IS SENDING BACK.

AS THE PAPER CRAWLS THROUGH THE MACHINE,

A WEIRD, UNEARTHLY SHAPE BEGINS TO TAKE FORM.

THE SIGNAL ISN'T CARRYING A MESSAGE.

IT'S CARRYING PICTURES.

AND NOT JUST ANY PICTURES,

THESE ARE THE FIRST PICTURES FROM THE SURFACE OF THE MOON.

Narrator: LUNA 9 HAS DONE IT.

FOR THE FIRST TIME IN HISTORY,

A SPACECRAFT HAS SURVIVED A LANDING ON ANOTHER WORLD

AND IS SENDING BACK THE PROOF,

AND IT'S THE SOVIETS WHO HAVE DONE IT.

THIS IS AN ENORMOUS MILESTONE IN SPACE EXPLORATION.

Narrator: THE SOVIETS ARE HOPING TO REAP A PROPAGANDA COUP

FROM THEIR TECHNOLOGICAL TRIUMPH.

BUT ONE THING STANDS IN THEIR WAY.

BECAUSE OF THE CURVATURE IN THE ROTATION OF THE EARTH,

THE SIGNAL FROM THE MOON IS HITTING BRITAIN FIRST

BEFORE IT GETS TO THE SOVIET UNION.

THEY CAN INTERCEPT THE SOVIET DATA

BEFORE THE KREMLIN GETS IT.

Narrator: THE PURE DUMB LUCK OF GEOGRAPHY

HAS PUT THE BRITISH IN PLACE

TO STEAL THE GLORY OF THE GREATEST ACHIEVEMENT

IN THE SPACE RACE SO FAR.

NOW IT'S A RACE AGAINST TIME

TO PREPARE THE PICTURES FOR PUBLICATION

BEFORE THE SIGNAL GETS TO THE SOVIETS.

Nichols: THESE ARE GOING TO BE

THE MOST IMPORTANT PICTURES IN THE SOVIET SPACE PROGRAM

SINCE THE LAUNCH OF THEIR FIRST PERSON INTO SPACE.

Narrator: WITHIN HOURS, THE FIRST IMAGES

FROM THE SURFACE OF THE MOON ARE PUBLISHED,

NOT IN SOVIET PAPERS, BUT IN BRITISH JOURNALS.

THE SOVIETS GOT SCOOPED ON THEIR OWN HISTORIC MOON IMAGES.

Nichols: THE DAILY EXPRESS

GETS THE BIGGEST SCOOP IN SPACE NEWS HISTORY.

COULD YOU IMAGINE... [CHUCKLES]

...HAVING THE ONE THING

YOU'VE BEEN WORKING ON FOR SO LONG,

TO GET THE FIRST IMAGE OF THE MOON ON THE SURFACE,

AND SOMEBODY PUBLISHES IT FIRST?

I WOULD BE MAD AS HELL.

Nichols: THIS HAD TO HAVE BEEN

A HUGE HUMILIATION FOR THE SOVIETS.

THIS WOULD BE LIKE THE AMERICANS

HEARING NEIL ARMSTRONG'S FIRST WORDS FROM THE MOON

BEING BROADCAST OVER RADIO MOSCOW.

Narrator: UP NEXT, MODERN PLANETARY SCIENTISTS

ARE SURE OF ONE THING ABOUT MARS...

WE KNOW THAT YOU CAN'T HAVE STANDING WATER ON MARS.

Bell: MARS IS A REALLY DRY PLACE.

IT IS A DESERT IN THE EXTREME, EXTREME WAYS.

Narrator: BUT EXCITING NEW EVIDENCE

SUGGESTS LIQUID WATER

IS FLOWING ON THE SURFACE OF THE RED PLANET.

WHERE THERE'S LIQUID WATER, AT LEAST ON EARTH,

THERE'S ALWAYS LIFE.

Narrator: FOR CENTURIES,

WE HAVE SPECULATED ABOUT LIFE ON MARS AND FEARED IT.

WE ALWAYS THINK OF LIFE ON MARS AS LITTLE GREEN MEN.

BUT MORE THAN LIKELY, IF THERE IS LIFE,

IT MAY BE VERY DIFFERENT

THAN WHAT WE FIND BACK HERE ON OUR OWN PLANET EARTH.

Narrator: NOW A NASA PROBE OVER THE RED PLANET

PRODUCES NEW EVIDENCE

SHOWING THIS COULD BE A REAL POSSIBILITY.

THERE MIGHT BE LIFE ON MARS.

AND WE'RE JUST LOOKING IN THE WRONG PLACE.

Narrator: SINCE SEPTEMBER 2006,

THE MARS RECONNAISSANCE ORBITER

HAS BEEN TAKING HIGH-RESOLUTION IMAGES

OF THE SURFACE OF THE RED PLANET.

FIVE YEARS INTO ITS MISSION,

THE PROBE CAPTURES SOMETHING PUZZLING.

LONG STREAKS APPEAR ON THE MARTIAN SLOPES,

AND NO ONE KNOWS WHAT THEY ARE.

THE ODD THING IS THAT THESE SURFACE MARKINGS

DISAPPEAR, REAPPEAR, AND THEN DISAPPEAR AGAIN.

THESE STREAKS ARE A BIG MYSTERY.

WE DON'T KNOW EXACTLY HOW THEY FORM,

AT LEAST, NOT ALL OF THEM.

SOMETIMES, THEY'RE THERE.

SOMETIMES, THEY DISAPPEAR.

Narrator: MARS HAS FEARSOME, POWERFUL STORMS

THAT SCOUR ITS SURFACE.

COULD THEY BE RESPONSIBLE FOR THESE MYSTERIOUS STREAKS?

AS THE ORBIT OF MARS DRAWS CLOSER TO THE SUN,

WE SEE MORE DUST STORMS

ACROSS THE SURFACE OF THE PLANET.

THE SUN HEATS THE SURFACE, THE AIR RISES,

AND DUST, SOMETIMES COVERING HALF THE ENTIRE PLANET,

CAN RAGE FOR MONTHS.

IMAGINE YOU'RE EXPLORING THE SURFACE.

OFF IN THE DISTANCE,

YOU WOULD SEE IT GROW DARKER AND DARKER.

A MONSTROUS CLOUD, 300, 600 FEET HIGH,

WOULD BE APPROACHING YOU.

[ THUNDER CRASHES ]

IN THIS CLOUD WOULD BE LIGHTNING BOLTS

SNAPPING THE GROUND.

THIS WOULD BE A HUGE GLOBAL, MARTIAN DUST STORM

COMING YOUR WAY.

Narrator: BUT EVIDENCE FROM MARS ROVER

SUGGEST THAT DUST STORMS SCOUR A SURFACE CLEAN.

THEY DON'T LEAVE LOCALIZED STREAKS

ACROSS THE GROUND.

ON EARTH, SIMILAR-LOOKING STREAKS

ARE CAUSED BY WATER INTERACTING WITH SALT

IN A DESERT ENVIRONMENT.

IN 2015, A NASA PROBE

PHOTOGRAPHS STREAKS IN ANOTHER MARTIAN CRATER.

IT PICKS UP THE SPECTROGRAPHIC SIGNATURE OF SALT.

WHEN IT PASSES OVER AGAIN, THE STREAKS HAVE GROWN.

Lee: ONE PASS, IT TAKES A PICTURE OF THESE GULLIES.

OVER THE NEXT PASS, A FEW MONTHS LATER,

NOW, THERE'S AN EXPANSIVE PATCH OF SALT.

Narrator: THIS CAN ONLY MEAN ONE THING.

WATER SOMEHOW HAD TO HAVE FLOWED OUT

AND DEPOSITED THE SALT.

Narrator: BUT THERE ISN'T SUPPOSED TO BE ANY WATER

ON THE SURFACE OF MARS.

D'Antonio: WE KNOW THAT YOU CAN'T HAVE STANDING WATER ON MARS.

IT'S A WELL-KNOWN FACT THAT

THE PRESSURE ISN'T HIGH ENOUGH, THE TEMPERATURE'S TOO LOW.

Bell: MARS IS A REALLY DRY PLACE.

IT IS A DESERT IN THE EXTREME, EXTREME WAY.

Narrator: THE VERY PRESENCE OF SALT WATER

TURNS ACCEPTED WISDOM ON ITS HEAD.

WE HAD BEEN THINKING THAT MARS WAS A PLACE

THAT WAS SO COLD, SO DRY

THAT IT RENDERED THE FLOW OF LIQUID WATER IMPOSSIBLE.

BUT IF YOU ACTUALLY PUT ENOUGH OF

A SPECIAL KIND OF SALT INSIDE THIS WATER,

IF YOU DISSOLVE IT,

ALL OF A SUDDEN, YOU ALLOW THAT WATER

TO REMAIN LIQUID EVEN AT VERY LOW TEMPERATURES.

Narrator: ANALYSIS OF THE LIGHT REFLECTED FROM THE DEPOSITS

REVEAL WHAT IT'S MADE OF.

THE CLOSEST MATCH IS A SALT CALLED PERCHLORATE.

PERCHLORATES IN HIGH CONCENTRATIONS IN LIQUID WATER

CAN LOWER THE FREEZING TEMPERATURE OF WATER

DOWN TO MINUS-70 DEGREES C.

THAT'S EXTRAORDINARY.

Narrator: MINUS 70 DEGREES CELSIUS

IS MINUS 94 DEGREES FAHRENHEIT.

REMARKABLY, PERCHLORATES CAN KEEP WATER FLOWING

EVEN AT SUCH EXTREME TEMPERATURES.

THIS WOULD EXPLAIN WHY THE WATER COULD LAST

AS LONG AS IT DID TRAVELING DOWNSLOPE

BEFORE IT DISAPPEARED AND VANISHED.

Narrator: BUT IT DOESN'T EXPLAIN

WHERE THE WATER CAME FROM IN THE FIRST PLACE.

UP-CLOSE ANALYSIS OF THE IMAGES

SUGGESTS AN EXCITING POSSIBILITY.

THESE STREAKS DON'T ORIGINATE AT THE TOP OF THE CRATER.

THEY ACTUALLY SEEM TO BE COMING OUT PARTWAY DOWN.

THIS CORRESPONDS TO AN UNDERGROUND LEVEL,

MAYBE AN AQUIFER -- RUNNING WATER UNDERGROUND.

IT'S COMING FROM UNDERNEATH THE SURFACE OF MARS.

IT'S UNDERGROUND WATER THAT'S COMING OUT.

Narrator: THE IMPLICATIONS ARE PROFOUND.

Lee: SO THIS WAS AN IMPORTANT OBSERVATION

BECAUSE IT TELLS YOU THAT LIQUID WATER

IS STILL FLOWING AT THE SURFACE OF MARS TODAY.

AND WHERE THERE'S LIQUID WATER, AT LEAST ON EARTH,

THERE'S ALWAYS LIFE.

Narrator: FOR LIFE ON MARS, CONDITIONS WOULD BE EXTREME.

SOME MICROBES ON EARTH LIKE PERCHLORATES.

THEY DON'T MIND BEING IN AN ENVIRONMENT

RICH IN PERCHLORATES,

BUT NOT AT THE CONCENTRATIONS THAT ARE NEEDED

TO KEEP WATER LIQUID ON MARS.

BUT WHAT WE CONSIDER TO BE A HOSTILE ENVIRONMENT

MIGHT NOT BE THAT HOSTILE

FOR ALL KINDS OR ALL FORMS OF LIFE.

MAYBE IT CAN FIND A WAY TO SURVIVE AND THRIVE

IN THAT KIND OF EXTREME ENVIRONMENT.

Narrator: ON EARTH,

FISH THRIVE IN THE BOILING HOT SULFUR POOLS

OF THE MARIANAS TRENCH

SHOWING THAT LIFE ALWAYS FINDS A WAY.

CERTAINLY, AS WE LEARN MORE ABOUT LIFE,

WE LEARN THAT IT CAN TOLERATE MORE EXTREME ENVIRONMENTS

THAN WE THOUGHT,

CERTAINLY, MORE EXTREME ENVIRONMENTS

THAN WE HUMANS TEND TO THINK OF AS HABITABLE.

SO I WOULD NOT EXCLUDE THE POSSIBILITY OF LIFE ON MARS

EVEN TODAY.

Narrator: THE DISCOVERY OF SALTY WATER

OOZING FROM BELOW THE MARTIAN SURFACE

OPENS UP AN IMPORTANT NEW AVENUE

IN OUR SEARCH FOR LIFE ON MARS.

McKay: THERE MIGHT BE LIFE ON MARS

AND WE'RE JUST NOT FINDING IT

BECAUSE WE'RE ONLY ON THE SURFACE,

AND IT'S UNDERGROUND.

WE'RE LOOKING IN THE WRONG PLACE.

Narrator: UP NEXT, HUNDREDS OF PEOPLE

WITNESS WEIRD PINK LIGHTS GLOWING OVER AREA 51.

ARE THESE SOME PREVIOUSLY UNKNOWN PHENOMENON FROM SPACE?

Narrator: THE U.S. MILITARY OFFERS NO EXPLANATION.

SO WHETHER IT'S INTERESTING SCIENCE OR EVIL SCIENCE,

THAT'S THE QUESTION, AND I DON'T KNOW.

Narrator: A BIZARRE, GLOWING CLOUD APPEARS OVER THE ARIZONA DESERT.

THESE DON'T LOOK LIKE ANYTHING THAT COME FROM EARTH.

Narrator: THE INTERNET IS FULL OF WILD THEORIES.

Pope: WHEN YOU LIVE IN THE STATE

NEXT TO PLACES LIKE ROSWELL AND AREA 51,

THESE ARE THE SORT OF THINGS THAT GO THROUGH YOUR MIND.

Narrator: BUT THE TRUTH IS FURTHER OUT THERE

THAN ANYONE COULD IMAGINE.

Narrator: FEBRUARY 2015.

A STRANGE, PINK CLOUD SUDDENLY LIGHTS UP ARIZONA'S NIGHT SKY.

THESE CLOUDS ARE AMAZING,

LIKE NOTHING ANYONE'S EVER SEEN BEFORE.

THEY'RE INTENSE COLOR, ALMOST GLOWING.

IT'S A COMPLETE MYSTERY.

Narrator: THE LOCATION OF THE SIGHTING

IMMEDIATELY CATCHES THE ATTENTION OF SOME.

Guarino: THIS IS U.F.O. CENTRAL.

THIS IS THE BIRTHPLACE OF U.F.O. CULTURE.

THESE DON'T LOOK LIKE ANYTHING THAT CAN COME FROM EARTH.

AND YOU MIGHT ASK,

"ARE THESE SOME PREVIOUSLY UNKNOWN PHENOMENON FROM SPACE?"

Pope: WELL, WHEN YOU LIVE IN THE STATE

NEXT TO PLACES LIKE ROSWELL AND AREA 51,

THESE ARE THE SORT OF THINGS THAT GO THROUGH YOUR MIND.

Narrator: IN THE SEARCH FOR A MORE SCIENTIFIC EXPLANATION,

SOME OBSERVERS WONDER IF THE EERIE GLOW

MIGHT BE SOME KIND OF ATMOSPHERIC EFFECT.

THEORY NUMBER ONE IS IT'S AN AURORA BOREALIS.

WHEN A SOLAR STORM OCCURS,

IT CAN GET DIRECTED TOWARDS THE EARTH.

AND ALL OF THOSE ENERGIZED PARTICLES

WILL INTERACT WITH THE MAGNETIC FIELD OF THE EARTH

AND GET DRIVEN TOWARDS THE PULL

AND CREATE THESE BEAUTIFUL LIGHT DISPLAYS.

Narrator: SUPER-CHARGED PARTICLES FROM THE SUN

BOMBARD OUR ATMOSPHERE,

CREATING A SPECTACULAR LIGHT SHOW

AS THEY EXPLODE ABOVE OUR WORLD.

BUT FOR AN AURORA TO BE SEEN SO FAR SOUTH,

A TRULY MASSIVE SOLAR STORM

WOULD HAVE TO ERUPT ON THE SURFACE OF THE SUN.

THERE WAS NO UNUSUAL SOLAR ACTIVITY

ON THE DAY CONCERNED.

SO THE SUN HAS BEEN BEHAVING NORMALLY.

Narrator: IT SEEMS THE MOST LIKELY EXPLANATION

IS THAT THIS CLOUD IS MAN-MADE.

COULD THE GOVERNMENT BE USING ARIZONA

AS A TESTING GROUND FOR SOME NEW FORM OF BIOLOGICAL WEAPON?

IT WOULDN'T BE THE FIRST TIME THIS HAS HAPPENED.

IN 1955, THE U.S. AIR FORCE CARRIED OUT A TRIAL

CODE-NAMED OPERATION BIG BUZZ

TO TEST WHETHER INSECTS COULD BE USED

TO SPREAD BIOLOGICAL WEAPONS.

IT DROPPED 330,000 BLOOD-THIRSTY MOSQUITOES

ON THE UNSUSPECTING STATE OF GEORGIA

TO SEE HOW MANY PEOPLE THEY WOULD BITE.

IS IT POSSIBLE THAT THE U.S. GOVERNMENT

COULD HAVE CONDUCTED EXPERIMENTS ON THE POPULATION OF ARIZONA?

WELL, THEY'VE DONE SUCH THINGS BEFORE.

WHO'S TO SAY THEY WOULDN'T DO THEM AGAIN?

Narrator: SOME BEGIN TO SUSPECT

THE MILITARY COULD STILL BE CARRYING OUT

EXPERIMENTAL PROJECTS ON U.S. SOIL.

Jeras: SOME PEOPLE BELIEVE

THAT THERE'S A SINISTER PLOT GOING ON WITH THE GOVERNMENT

THAT THEY'RE ACTUALLY SPRAYING CHEMICALS IN THE SKY

THAT WOULD CREATE THESE TRAILS OF CLOUDS

POSSIBLY IN DIFFERENT COLORS.

Narrator: SOME EVEN WONDER

IF THESE CHEMTRAILS CONTAIN MIND-ALTERING SUBSTANCES.

THERE'S A LOT OF DISCUSSION.

WHAT'S A CHEMTRAIL?

I KNOW PEOPLE WHO THINK THEY'RE POISONOUS.

Narrator: BUT NOT EVERYONE IS CONVINCED

THE PINK CLOUD IS A CHEMTRAIL.

THERE'S NO EVIDENCE THAT CHEMTRAILS ARE REAL.

IN FACT, IF YOU WANTED TO DISPERSE

A MIND-ALTERING SUBSTANCE,

YOU WOULDN'T DO IT AT THE HEIGHT THAT AIRPLANES FLY.

BUT IT TURNS OUT THAT NASA

HAS BEEN SPRAYING CHEMICALS INTO THE ATMOSPHERE.

IT EVEN ISSUED A PRESS RELEASE EXPLAINING WHY.

AT 5:26 A.M. ON FEBRUARY 25th,

NASA LAUNCHED A ROCKET FROM THE WHITE SANDS MISSILE RANGE.

NASA LAUNCHED A ROCKET HIGH UP INTO THE ATMOSPHERE

AND RELEASED CHEMICALS WHICH CREATED THE COLORED CLOUD.

Narrator: THE ROCKET WAS CARRYING A CHEMICAL COMPOUND

CALLED SUMERIAN VAPOR.

IT'S A CHEMICAL THAT WHEN IT REACTS WITH

THE CHARGED PARTICLES IN THE IONOSPHERE

TURNS PINK.

Narrator: THE ROCKET WAS DESIGNED TO REACH AN ALTITUDE OF 100 MILES

BEFORE IT SPRAYED THE SUMERIAN VAPOR

INTO THE IONOSPHERE.

THE VAPOR SIMULATES THE PLASMA THAT ENVELOPES OUR WORLD

FORMED BY EARTH'S ELECTRICAL FIELD.

BY ANALYZING HOW THIS HAPPENS,

NASA HOPES TO LEARN

HOW THE OUTERMOST LAYER OF OUR ATMOSPHERE WAS FORMED.

IT TURNS OUT,

NASA HAS BEEN SEEDING THE ATMOSPHERE WITH CHEMICALS

FOR DECADES.

Guarino: SINCE THE '50s,

NASA'S BEEN RELEASING COLORFUL VAPORS INTO THE AIR

FOR SCIENTIFIC EXPERIMENTS.

Narrator: THIS ATMOSPHERIC EXPERIMENT

IS JUST THE LATEST IN A LONG LINE

GOING BACK MORE THAN HALF A CENTURY

TO THE EARLIEST DAYS OF NASA.

COMING UP, THE SOVIET SPACE WEAPON

THAT THREATENS AMERICA'S SKIES.

Jurek: IT CAN LAUNCH WITHOUT WARNING.

IT'S DEATH FROM THE SKY.

Narrator: THE SOVIETS LAUNCH A WEAPON INTO SPACE.

IT WAS THE BIGGEST WEAPON ANYONE'S EVER PUT INTO SPACE.

Narrator: THE U.S. FEARS THE WORST.

Jurek: THE REAL FEAR IS THAT

THEY'VE SEIZED THE HIGH GROUND FROM SPACE.

Narrator: 1974, THE HEIGHT OF THE COLD WAR.

THE U.S.A. AND THE SOVIET UNION

ARE LOCKED IN A NUCLEAR ARMS RACE.

IT'S A DANGEROUS SHADOW GAME OF BLUFF AND COUNTER BLUFF.

Obert: THE STANDOFF BETWEEN

THE UNITED STATES AND THE SOVIET UNION

LED TO A WORLDWIDE CONCERN OVER A NUCLEAR EXCHANGE

THAT WOULD AFFECT THE ENTIRE PLANET.

WE HAVE BOTH SIDES BRAINSTORMING VARIOUS METHODS

OF USING SPACE FOR GETTING SOME KIND OF MILITARY ADVANTAGE.

Narrator: IN JUNE, THE SOVIET UNION ANNOUNCES

THE LAUNCH OF THE SALYUT 3,

AN EXPERIMENTAL SPACE STATION MANNED BY TWO COSMONAUTS.

THE PENTAGON GOES ON HIGH ALERT.

THEY WEREN'T SURE WHAT WAS GOING ON ABOARD THESE STATIONS.

THEY HAD SUSPICIONS.

Jurek: THE REAL FEAR IS THAT

THEY'VE SEIZED THE HIGH GROUND FROM SPACE.

Narrator: THERE'S NO QUESTION

THE RUSSIAN SPACE STATION HAS MILITARY CAPABILITIES.

THERE'S A CREDIBLE THREAT

THAT SALYUT 3 COULD GET THE DROP ON THE U.S.A.

HANGING OVER THE ENTIRE COLD WAR WAS THE CONCERN

THAT SPACE WAS GONNA BE THE WAY YOU DELIVER NUCLEAR WEAPONS.

Jurek: THESE ARE THE DARKEST DAYS OF THE COLD WAR.

AND YOU HAVE TO BE CONCERNED WHEN THE SOVIET'S GO INTO SPACE,

HAVE THEY TAKEN A WEAPON WITH THEM?

Narrator: THERE ARE OBVIOUS ADVANTAGES

TO EXECUTING A NUCLEAR STRIKE FROM SPACE.

YOU CAN LAUNCH WITHOUT WARNING.

BUT MORE IMPORTANTLY, IT'S DEATH FROM THE SKY.

Narrator: BUT DROPPING A NUCLEAR BOMB FROM SPACE

IS FAR EASIER SAID THAN DONE.

Oberg: YOU'RE IN AN ORBIT

THAT ONLY PASSES OVER POTENTIAL TARGETS

A FEW MINUTES, SEVERAL TIMES A DAY.

AND THE REST OF THE TIME,

YOU'RE COMPLETELY OUT OF RANGE OF EVERY PLACE ON EARTH.

SO PUTTING A WEAPON UP THERE WILL ONLY BE USEFUL

UNDER VERY NARROW WINDOWS.

Jurek: THE AMERICANS QUICKLY DECIDE

THAT THE RUSSIANS DON'T HAVE THE CAPABILITY

TO LAUNCH NUCLEAR WEAPONS FROM SPACE.

BUT THAT DOESN'T RULE OUT THE POSSIBILITY

IN THE NEAR FUTURE.

Narrator: EVEN IF THE RUSSIANS HAVEN'T BUILT A NUCLEAR DELIVERY SYSTEM,

IT'S POSSIBLE THAT SALYUT 3 COULD BE DESIGNED

TO STOP U.S. MISSILES GETTING THROUGH.

WHEN AN INTERCONTINENTAL BALLISTIC MISSILE IS FIRED,

THE TRAJECTORY OF THE ROCKET

MEANS THE WARHEAD BRIEFLY LEAVES THE EARTH'S ATMOSPHERE.

IT'S THE PERFECT OPPORTUNITY TO DESTROY IT.

INTERCEPTING A NUCLEAR MISSILE ONCE IT RE-ENTERS THE ATMOSPHERE

IS VIRTUALLY IMPOSSIBLE.

THE TIME TO CAPTURE IT AND TO INTERCEPT IT

WILL BE WHEN IT'S STILL UP IN SPACE.

Narrator: U.S. MILITARY INTELLIGENCE INDICATES

THE SOVIET SPACE PROGRAM

COULD BE TAKING THIS TO THE NEXT LEVEL.

THE SOVIETS WERE WORKING ON A MEGA LASER.

DURING THIS SALYUT 3 LAUNCH,

ONE OF THE SPACE WEAPONS WAS A LASER DEATH RAY.

Narrator: BUT IN THE 1970s,

LASER WEAPONRY STILL LIES IN THE REALM OF SCIENCE FICTION.

Jurek: THE REALITY IS

A LASER INTERCEPT PLATFORM FROM SPACE

JUST WOULDN'T WORK.

THE RUSSIANS, AND THE AMERICANS FRANKLY,

DIDN'T HAVE THE TECHNOLOGY.

Narrator: U.S. INVESTIGATORS REMAIN IN THE DARK

UNTIL THE 1990s WHEN THE FALL OF THE SOVIET UNION

RELEASES FILES THAT SHED NEW LIGHT

ON SALYUT 3'S TRUE PURPOSE.

THE COSMONAUTS WERE SPIES.

Oberg: BOTH COUNTRIES KEPT AN EYE ON EACH OTHER'S FORCES

MOSTLY THROUGH SPY SATELLITES.

SALYUT 3 WAS THEIR MILITARY RECONNAISSANCE SATELLITE PROGRAM.

BUT THE SOVIET SPY SATELLITES

ARE NOT NEARLY AS SOPHISTICATED AS THE AMERICANS'.

FOR THE SOVIETS, THE ANSWER SEEMS TO HAVE BEEN

A MANNED VEHICLE THAT THEY WILL PUT INTO SPACE.

AND IT WILL KEEP WATCH --

CAREFUL WATCH ON THE UNITED STATES.

Narrator: EVEN IN SPACE,

THE KREMLIN BELIEVE COSMO-SPIES ON SALYUT 3

WEREN'T COMPLETELY OUT OF THE REACH OF THE U.S. MILITARY.

TO PROTECT THE ORBITING RUSSIAN SPIES,

THE SOVIETS TOOK THE FIRST DANGEROUS STEP

TOWARD WEAPONIZING SPACE.

THE SOVIETS KNEW THE AMERICANS WOULD THINK IT WAS SO IMPORTANT,

THEY MIGHT BE TEMPTED TO ATTACK IT.

PARANOIA, WHICH WE FACE AT THIS TIME,

IS THAT AN AMERICAN DESTROYER SATELLITE

CAN COME VERY CLOSE TO THE MILITARY SPACE STATION

AND LET THEM TO RAM IT OR EVEN DESTROY IT.

Oberg: TO PREVENT THAT,

THE NEXT OBVIOUS STEP FOR THE SOVIETS

WAS TO ARM THE STATION WITH A DEFENSIVE GUN.

Narrator: SALYUT 3 MADE HISTORY

AS THE FIRST SPACE STATION ARMED WITH AN ANTI-AIRCRAFT CANNON

THAT COULD FIRE HIGH-EXPLOSIVE SHELLS

AT CLOSE TO 1,500 MILES PER HOUR --

AN R-23M KARTECH INTERCEPTOR.

THE CANNON THAT THE SOVIETS PUT ON THEIR MILITARY SATELLITES

WAS THE BIGGEST WEAPON ANYONE'S EVER PUT INTO SPACE.

IT WAS DESIGNED TO SHOOT DOWN ANY AMERICAN SPACECRAFT

TRYING TO APPROACH THE RUSSIAN STATION.

Narrator: NOBODY HAD EVER FIRED A RAPID-FIRE CANNON

IN SPACE BEFORE.

THERE WAS A REAL DANGER

THAT ITS RECOIL MIGHT PUT THE STATION INTO A SPIN.

FIRING THIS GUN IS A DANGEROUS OPERATION.

SO THE SOVIETS DECIDE TO TEST-FIRE IT.

Narrator: THE RESULTS OF THE TEST

IS STILL A CLOSELY-GUARDED MILITARY SECRET.

SECRECY AND PARANOIA

IN A MILITARY ESTABLISHMENT OF THE SOVIET UNION

IS ABSOLUTELY PARAMOUNT.

IT'S OVERWHELMING.

Gervovitsch: THE SOVIETS DON'T WANT PEOPLE TO KNOW ABOUT THEIR FAILURES.

AND FOR THIS REASON,

THEY HIDE THE ENTIRE PROGRAMS THAT THEY ARE WORKING ON.

WE KNOW THAT THE GUN WAS FIRED.

BUT STILL, WE DON'T KNOW IF IT HIT THE TARGET.

Narrator: THE R-23M IS NEVER MENTIONED AGAIN.

BUT IRONICALLY, IT PAVES THE WAY

FOR SOMETHING ENTIRELY DIFFERENT.

Oberg: SALYUT 3 AND SALYUT 5

WERE PART OF A PROGRAM CALLED ALMAZ WHICH WAS THEIR

MILITARY RECONNAISSANCE SATELLITE PROGRAM.

ONE OF THE LEFTOVER MODULES IN THAT PROGRAM WAS SOLD TO NASA

AS THE BASE BLOCK OF THE INTERNATIONAL SPACE STATION.

SO OUR INTERNATIONAL SPACE STATION PROGRAM

UP THERE AS A SYMBOL OF WORLD PEACE

IS BUILT ON A SPACECRAFT

ORIGINALLY DESIGNED TO CARRY A WEAPON INTO SPACE.

SO IF THAT'S NOT SWORDS INTO PLOWSHARES,

I DON'T KNOW WHAT IS.

Narrator: COMING UP, THE MYSTERIOUS MALFUNCTION

THAT MAY HAVE POISONED THE I.S.S.

WHEN YOU HEAR THE ALARM IN THE SPACE STATION,

YOU NEED TO MOVE FAST.

THERE'S NO TIME TO FIGURE OUT WHAT THE PROBLEM IS.

Narrator: AN ALARM MYSTERIOUSLY GOES OFF

IN THE INTERNATIONAL SPACE STATION.

THERE'S SOME KIND OF TOXIC GAS LEAK IN THE ENVIRONMENT.

Oberg: IT HAS AN UNPLEASANT, PUNGENT SMELL.

IT COULD BE THE SMELL OF DEATH.

Narrator: NASA STRUGGLES TO FIGURE OUT WHAT'S GOING ON.

NOW MISSION CONTROL IS TOTALLY CONFUSED.

Narrator: IS SOMEONE OR SOMETHING

TRYING TO SABOTAGE THE I.S.S.?

JANUARY 2015.

ASTRONAUTS ONBOARD THE INTERNATIONAL SPACE STATION

EAGERLY AWAIT THE ARRIVAL OF A SUPPLY SHIP.

NOT ONLY IS THERE EXTRA SPARE PARTS,

THERE'S GIFTS, FRESH FOOD.

USUALLY, THIS IS A FUN TIME. THIS IS A GOOD TIME.

BUT THAT GOOD MOOD IS ABOUT TO BE SHATTERED.

Narrator: TWO DAYS LATER,

THE ASTRONAUTS ARE STILL UNPACKING

WHEN SOMETHING COMPLETELY UNEXPECTED

INTERRUPTS THEIR ROUTINE.

AS THEY'RE UNLOADING ALL THIS EQUIPMENT,

THE ALARM STARTS SOUNDING.

Orwoll: WHEN YOU HEAR THE ALARM IN THE SPACE STATION,

YOU NEED TO MOVE FAST.

Narrator: THE SENSORS INDICATE

THERE IS SOMETHING WRONG

WITH THE AIR INSIDE THE SPACE STATION.

THERE'S SOME KIND OF TOXIC GAS LEAK IN THE ENVIRONMENT

WHICH IS A HUGE PROBLEM.

YOU CAN'T ROLL DOWN A WINDOW TO AIR OUT THE SPACE.

YOU HAVE TO DEAL WITH THE ENVIRONMENT AS IT IS.

Narrator: THE CREW IMMEDIATELY PUT ON GAS MASKS

AND RETREAT TO THE RUSSIAN SECTION.

ON THE GROUND,

NASA TECHNICIANS SCRAMBLE TO FIND OUT

WHAT THE SENSORS HAVE DETECTED.

THE DATA COMING FROM THE SENSORS DOESN'T SEEM TO MAKE SENSE.

IT SUGGESTS A LEAK OF TOXIC AMMONIA.

IT HAS AN UNPLEASANT, PUNGENT SMELL.

AND IF YOU SMELL IT FOR ANY REASON,

IT COULD BE THE SMELL OF DEATH.

SO THE KEY QUESTION NOW IS, WHERE IS THE LEAK?

Narrator: NASA SUSPECTS

THAT IT'S COMING FROM THE ONBOARD COOLING SYSTEM

WHICH USES AMMONIA TO RADIATE HEAT FROM THE STATION

OUT INTO SPACE.

THAT KIND OF LEAK JUST SHOULDN'T HAPPEN.

Oberg: IF THE COOLING SYSTEM PLUMBING HAS RUPTURED,

AMMONIA COULD LEAK INTO THE AMERICAN SIDE

MAKING IT UNINHABITABLE.

Teitel: THE SYSTEM THAT IS USED

TO DISSIPATE HEAT FROM THE STATION

OUT INTO SPACE SAFELY

IS NOW POSING A HUGE RISK TO THE ASTRONAUTS.

THE CONCERN WAS THAT THE AMMONIA

WAS GETTING FROM THE OUTSIDE LOOPS

THROUGH SOME KIND OF A LEAK.

Narrator: BUT TO CHECK THAT,

THE ASTRONAUTS WILL HAVE TO PUT THEMSELVES IN DANGER.

FIGURING OUT WHAT CAUSED THE ORIGINAL ALARM

REQUIRES YOU TO MEASURE THE AMMONIA LEVEL

IN THE AMERICAN SIDE.

BUT THE EQUIPMENT TO DO THAT IS ON THE AMERICAN SIDE

WHERE YOU'RE NOT ALLOWED TO GO.

WHAT DO YOU DO NOW?

[ INDISTINCT RADIO CHATTER ]

Narrator: LOOKING BACK THROUGH THE MISSION LOGS,

THE ONLY UNUSUAL EVENT IN THE LAST TWO DAYS

IS THE SUPPLY SHIP DOCKING.

THE DOCKING HATCH IS RIGHT NEXT TO THE COOLING SYSTEM.

PERHAPS, THERE COULD'VE BEEN A COLLISION.

[ INDISTINCT RADIO CHATTER ]

DATA FROM THE DOCKING PROCEDURE SHOWS NO EVIDENCE OF AN IMPACT.

EVEN MORE MYSTERIOUSLY,

READINGS FROM THE THERMAL CONTROL SYSTEM

SHOW NO EVIDENCE THAT AMMONIA IS LEAKING.

SOMETHING ELSE IS GOING ON.

NASA SENDS A MESSAGE TO THE ASTRONAUTS

THAT THERE'S NO AMMONIA INSIDE THE MODULE.

Oberg: THE CREW OPENS THE HATCH AND SLOWLY REENTERS THE MODULE.

THEY FIND OUT THERE IS NO AMMONIA IN THERE.

BUT AS SOON AS THEY DO, A CABIN PRESSURE ALARM SOUNDS.

AND THEY'RE FORCED TO EVACUATE YET AGAIN.

Narrator: THE CREW RETREAT BACK TO THE RUSSIAN SIDE OF THE STATION.

NOW, MISSION CONTROL IS TOTALLY CONFUSED.

ON THE GROUND, MISSION CONTROLLERS

ARE RECEIVING ERRATIC INFORMATION

FROM THE SPACE STATION'S COMPUTERS.

NO ONE CAN FIGURE OUT WHAT'S GOING ON.

Narrator: OUT OF OPTIONS, NASA GOES BACK TO BASICS.

MISSION CONTROL TAKES THE I.T. APPROACH

AND HAS THEM TURN THE COMPUTERS OFF

AND THEN BACK ON.

IT'S COMPUTERS 101.

BUT GUESS WHAT?

IT WORKS.

Narrator: THE ALARM RESETS,

AND THE CREW CAN RE-ENTER THE MODULE.

AN INVESTIGATION DETERMINES

THAT A COMPUTER MALFUNCTION CAUSED THE SECOND ALARM.

Orwoll: THE PRESSURE SENSORS WERE SET OFF

FOR A COUPLE OF REASONS.

FIRST, THE VENTILATION SYSTEM WAS TURNED OFF.

SECOND, THE BREATHING MASKS THEY WERE USING

WERE ADDING GAS TO THE MODULE

WITH EVERY BREATH THAT THEY TOOK.

MAN: This is a false indication.

IN THIS CASE, FORTUNATELY,

IT TURNED OUT TO BE A FALSE ALARM.

Oberg: AT LAST, THE SENSORS SAY EVERYTHING'S NORMAL.

THEY NEVER DID FIGURE OUT

WHAT HAD CAUSED THE ORIGINAL ALARM TO GO OFF.

Narrator: WHATEVER CAUSED THE ORIGINAL EMERGENCY

COULD STILL POSE A THREAT TO THE I.S.S. TODAY.

Narrator: STILL TO COME,

ASTRONOMERS BATTLE WITH A 350-YEAR-OLD MYSTERY.

OUT OF NOWHERE, IT APPEARED,

THEN IT DISAPPEARED,

THEN IT RE-APPEARED,

THEN IT DISAPPEARED AGAIN.

WHAT'S GOING ON?

Narrator: RENAISSANCE ASTRONOMERS

SEE SOMETHING THAT OUGHT TO BE IMPOSSIBLE.

Oluseyi: IF YOU DISCOVER A NEW STAR IN THE SKY,

THAT'S EXCITING.

THAT STAR DISAPPEARS, THAT'S WEIRD.

THAT STAR RE-APPEARS, THAT IS A MYSTERY.

Narrator: THE 350-YEAR-OLD MYSTERY

TRIGGERS ONE OF THE LONGEST INVESTIGATIONS

IN THE HISTORY OF ASTRONOMY.

1670, FRANCE.

A BRIGHT LIGHT SUDDENLY SHINES IN THE NIGHT SKY.

350 YEARS AGO,

ASTRONOMERS SAW A STAR APPEAR IN THE SKY

THAT THEY HADN'T SEEN BEFORE.

SCIENTISTS KNEW THAT SOMETIMES STARS BECAME BRIGHTER,

AND THEN, THEY COULD DISAPPEAR.

WHAT THEY'D NEVER SEEN BEFORE

WAS A STAR THAT BECAME BRIGHTER, DISAPPEARED,

AND THEN, SOMEHOW, RE-APPEARED AGAIN.

Narrator: THIS IMPOSSIBLE STAR

COULD'VE EASILY BEEN DISMISSED AS A MISTAKE AND FORGOTTEN.

THIS ALL HAPPENED A LONG TIME AGO.

SO MAYBE THERE WAS JUST AN ERROR IN THEIR OBSERVATION.

BUT THE MAN WHO DOCUMENTED THIS ANOMALY

WAS ONE OF THE GREAT FATHERS OF MODERN ASTRONOMY --

GIOVANNI DOMENICO CASSINI.

IT'S REALLY UNLIKELY THAT

CASSINI OR SOME OF THE OTHER CONTEMPORARY ASTRONOMERS

ARE GOING TO MAKE A MISTAKE

ABOUT NOTICING A STAR APPEAR AND DISAPPEAR.

ACROSS EUROPE, PEOPLE ARE SHARING INFORMATION.

THEY'RE CORROBORATING THEIR NOTES,

THEY'RE MAKING METICULOUS DETAILS,

AND EVERYTHING IS LINING UP.

SOMETHING STRANGE IS GOING ON WITH THIS STAR.

Narrator: INITIALLY, CASSINI THOUGHT HE HAD WITNESSED

THE INTENSE, SHORT-LIVED BURSTS OF LIGHT

THAT FADE AND RETURN WHEN A DYING STAR EXPLODES.

AT THE TIME, THEY KNEW ABOUT NOVA --

STARS THAT EXPLODE AND BRIGHTEN CONSIDERABLY FOR SOME TIME.

Narrator: BUT THIS LIGHT WAS PULSING TOO QUICKLY TO BE A NOVA.

NOVAE DO BRIGHTEN, AND FADE, AND BRIGHTEN AGAIN.

BUT THE FASTEST ONES DO THIS ON THE SCALE OF DECADES,

NOT ON THE SCALE OF A YEAR.

Narrator: SO IF THE IMPOSSIBLE STAR ISN'T A NOVA,

THEN WHAT DID CASSINI SEE?

IT WASN'T UNTIL ALBERT EINSTEIN

PROPOSED THE GENERAL THEORY OF RELATIVITY

250 YEARS LATER

THAT ANOTHER POSSIBILITY AROSE.

ANOTHER IDEA FOR THIS SORT OF EVENT

IS THAT A STAR IS BEING TORN APART

AND EATEN BY A BLACK HOLE.

BUT IN THE DAYS OF CASSINI,

THEY DIDN'T EVEN KNOW BLACK HOLES EXISTED.

Narrator: A BLACK HOLE IS BORN

WHEN A LARGE STAR BURNS OUT AND COLLAPSES IN ON ITSELF.

ITS IMMENSE GRAVITATIONAL PULL DEVOURS ALL AROUND IT,

STRETCHING MATTER TO INFINITY

AS IT SUCKS EVERYTHING INTO ITS MAW, EVEN LIGHT.

WHEN A BLACK HOLE EATS A STAR, THE STAR IS TORN APART,

AND IT GETS STRETCHED OUT INTO A DISC AROUND THE STAR.

QUITE OFTEN, YOU'LL GET FLASHES OF LIGHT

NEAR THE EDGE OF THE BLACK HOLE

THAT MIGHT BE VISIBLE

IF IT HAPPENED CLOSE ENOUGH TO THE EARTH.

Narrator: BUT A BLACK HOLE ONLY EXPLAINS

PART OF THE PHENOMENON CASSINI OBSERVED.

THIS THEORY FITS SOME OF THE FACTS.

BUT WHEN A BLACK HOLE EATS A STAR, IT'S GONE.

YOU'RE NOT GONNA SEE IT RE-APPEAR.

Narrator: SCIENTISTS REMAIN IN THE DARK UNTIL 2015

WHEN ASTRONOMER TOMASZ KAMINSKI

USES CUTTING-EDGE TECHNIQUES TO STUDY THE IMPOSSIBLE STAR.

KAMINSKI REALIZES

THAT THE NEBULA OF GAS SURROUNDING THE STAR

IS TOO MASSIVE TO BE THE PRODUCT OF A SINGLE NOVA EXPLOSION.

THIS INDICATES THAT IT ISN'T

THE REMNANTS OF ONE STAR, BUT TWO.

IT SUGGESTS CASSINI MAY HAVE WITNESSED

AN INCREDIBLY RARE COSMIC EVENT.

THE OBSERVATIONS OF THESE NEBULA ARE ABSOLUTELY CRUCIAL

IN EXPLAINING HOW THIS STAR APPEARED AND THEN DISAPPEARED.

THIS IS CALLED A "RED TRANSIENT" OR A "LUMINOUS RED NOVA."

Oluseyi: A RED TRANSIENT OCCURS

WHEN TWO STARS LIKE THE SUN, MAIN-SEQUENCE STARS, COLLIDE.

Narrator: THE RESULTING EXPLOSION

THROWS OFF SUCH A HUGE QUANTITY OF DEBRIS

THAT THE DUST CLOUD ENVELOPES BOTH STARS.

Genge: DEBRIS COOLS AND HIDES THE LIGHT FROM THE STARS.

AND WHEN IT EVENTUALLY CLEARS,

WE CAN SEE THE STAR AGAIN.

AND, SO, THE STAR APPEARS TO DISAPPEAR AND THEN REAPPEAR.

EVENTS LIKE THESE ARE INCREDIBLY RARE.

EVEN WHEN GALAXIES COLLIDE,

IT IS VERY RARE THAT STARS COLLIDE.

Narrator: IF THIS REALLY IS WHAT'S GOING ON,

THE FATHER OF ASTRONOMY RECORDED SOMETHING

THAT VERY FEW OBSERVERS HAVE EVER SEEN.

Genge: CONSIDERING HOW RARE THESE EVENTS ARE,

IT'S AMAZING THAT CASSINI ACTUALLY SAW ONE IN ACTION

WHEN, TODAY, EVEN USING MODERN TELESCOPES,

THEY ARE REALLY DIFFICULT TO FIND.

IN FACT, WE DON'T EVEN KNOW WHEN WE WILL SEE THE NEXT ONE.