Science Matters with Lawrence Krauss

Arizona State University physicist Lawrence Krauss will discuss the latest big science news.

Transcript:

TED: TIME NOW FOR A LIVELY AND INFORMATIVE UPDATE OF THE LATEST SCIENCE NEWS WITH OUR GOOD FRIEND, BEST-SELLING SCIENCE WRITER AND WORLD RENOWNED PHYSICIST. HERE HE IS, LAWRENCE KRAUSS. GOOD TO SEE YOU.

LAWRENCE KRAUSS: ITS GOOD TO SEE YOU. I'M NOT OVERLY PREPARED. [LAUGHTER]

TED: ARE YOU OFF THE CUFF?

LAWRENCE KRAUSS: NO NOT OFF THE CUFF, NOT QUITE, TRYING TO GET THAT EQUILIBRIUM IN THERE.

TED: I'LL TRY NOT TO INTERRUPT YOU. BUT IF YOU SAY SOMETHING THAT I THINK IS WRONG.

LAWRENCE KRAUSS: I'M DEFLECT.

TED: THE ROSETTA MISSION APPARENTLY IS ENDING. WHAT IS THE ROSETTA MISSION AND HOW BIG A DEAL IS THIS?

LAWRENCE KRAUSS : WE'VE TALKED ABOUT IT BEFORE AS YOU MAY REMEMBER. THIS IS A MISSION TO A COMET. THE FIRST MISSION TO ORBIT A COMMIT FROM THE OUTER PART OF OUR SOLAR SYSTEM, PROBABLY CAME FROM OUTSIDE OF NEPTUNE AND THIS -- AND WHAT IT'S DOING -- IT'S SAMPLING MATERIAL THAT IS PRIMORDIAL FROM THE BEGINNING OF OUR SOLAR SYSTEM, 4.5 BILLION YEARS AGO. AND WE'VE KNOWN ABOUT COMETS AND WE'RE SEEN THEM BUT IMAGINE SENDING A SPACECRAFT THERE TO NOT ONLY LOOK AT IT, BUT TO LAND A LANDER ON IT. IT TOOK A DECADE TO GET THERE. YOU HAVE TO CATCH UP TO A THING THAT'S GOING TOWARD THE SUN AND FOLLOW IT ALONG. THERE'S A ROSETTA MISSION AND IT LED A LANDER, WHICH AS YOU MAY REMEMBER, WE TALKED ABOUT THE FACT IN AN EARLIER EPISODE, LANDED AND BOUNCED INTO A CREVASSE AND IT JUST WAS SUDDENLY SEEN AGAIN.

TED: PEEKING OUT OF THE THING THERE.

LAWRENCE KRAUSS: EXACTLY. IT IS STUDIED…THE MATERIAL THAT MAKES UP A COMET WHICH IS REALLY PRIMORDIAL MATERIAL. IT LOOKS LIKE TWO BIG SNOWBALLS THAT SORT OF CRASHED TOGETHER.

TED: HOW BIG IS THAT THING THAT WE'RE LOOKING AT?

LAWRENCE KRAUSS: THE SIZE OF IT IS PROBABLY LESS THAN A KILOMETER OR TWO, MAYBE A FEW KILOMETERS ACROSS.

TED: NOT THAT BIG.

LAWRENCE KRAUSS: IT'S BIG ENOUGH TO HOLD ITSELF TOGETHER GRAVITATIONALLY, BUT BARELY. ONE OF THE THINGS THAT THE MISSION DISCOVERED IT'S ACTUALLY 70% OF THE VOLUME OF THAT THING IS EMPTY. LIKE FRESHLY POWDERED SNOW AND COVERED BY ROCK AND SAND ON THE OUTSIDE,THERES NOT SO MUCH ICE IN THERE. IT'S MOSTLY DIRTY ROCK AND ORGANIC MATERIAL WHICH IS IMPORTANT BECAUSE WE THINK SOME OF THOSE ORGANIC MATERIALS MAY HAVE GIVEN THE NECESSARY AGREEMENTS FOR LIFE OR EARTH.

TED: LOOK AT THAT.

LAWRENCE KRAUSS: IT LOOKS LIKE A LITTLE PLANET.

TED: IT DOES.

LAWRENCE KRAUSS: BUT THE GRAVITY IS SO SMALL, WHEN ROSETTA ENDS ITS MISSION IN A POETIC WAY. THE COMET HAD GONE AROUND THE SUN AND STARTED ABOUT TWO YEARS AGO, WHEN IT WAS ON ONE SIDE OF THE SUN, FOLLOWING ALONG AS IT GOT ACTIVE AND EXCITED AND NEAR THE SUN AND THEN ON THE FAR TAIL OF THE SUN, IT -- IT -- THE SUNLIGHT WAS DETERIORATING AND IT'S SOLAR POWERED SO IT WAS GOING TO DIE SO, THEY LET THE SATELLITE CRASH INTO THE COMET LET IT CRASH INTO THE COMET BY LETTING THE GRAVITY OF THE COMET ATTRACT IT AT A SPEED TWO KILOMETERS PER HOUR WHICH IS SLOWER THAN YOU WALK HOME AND THEN IT SORT OF FLAT-LINED OUT. CRASHED GENTLY, BOUNCED GENTLY AND STOPPED SENDING THE SIGNAL AND THAT'S THE END OF THE MISSION THAT TOOK A DECADE, ITS AMAZING.

TED: SO WHAT HAPPENS NOW? NO MORE DATA OR INFORMATION, IT SITS THERE AND TAKES A RIDE. HOW LONG DOES IT TAKE A RIDE?

LAWRENCE KRAUSS : THAT'S A GOOD QUESTION, IT COULD BE TAKING A RIDE FOR AS LONG AS THE COMET SURVIVES.

TED: HOW LONG DO YOU THINK IT'S GOING TO BE?

LAWRENCE KRAUSS: I DON'T KNOW. THESE COMETS HAVE ORBITS THAT TAKE MANY MANY YEARS AND EVENTUALLY COULD CRASH INTO THE SUN, THIS THING COULD GO AROUND MANY TIMES IN THE SPACECRAFT AND THE LITTLE LANDER, STUCK IN THE CREVASSE... EACH TIME THE COMET GOES AROUND. A LOT OF THE MATERIAL IS EVAPORATED OR ABLATED BY THE MATERIAL OUT OF THE SUN.

TED: AND EVENTUALLY THE ROSETTA IT WILL BE JETTISONED OFF.

LAWRENCE KRAUSS: IT WILL BE IN THE ORBIT UNTIL THE COMET CRASHES OR HITS THE SUN.

TED: ANY SIMILAR MISSIONS TO THIS READY TO GO?

LAWRENCE KRAUSS : THERE ARE OTHER MISSIONS TO COMETS PLANNED BUT I DON'T KNOW WHEN THEY'RE GOING TO LAND. I THOUGHT THIS MIGHT BE A LOADED QUESTION.

TED: I MIGHT KNOW SOMETHING, BUT I CAN'T TELL YOU. THERE'S A MOON OF JUPITER THAT APPARENTLY HAS WATER-LIKE --

LAWRENCE KRAUSS: WHAT'S NEAT, EUROPA, WE'VE TALKED ABOUT EUROPA BEFORE, IT'S A ICE COVERED MOON, AND WHAT WAS DISCOVERED, OF COURSE, IS THAT THE GRAVITY OF JUPITER IS STRONG ENOUGH, TO CREATE A LIQUID OCEAN UNDER THAT ICE OF THE GRAVITY IS SLOSHING THINGS AROUND AND HEATS IT UP ENOUGH THAT THERE'S A DEEP OCEAN THAT CONTAINS MORE WATER THAN ALL OF THE OCEANS ON EARTH. WE THOUGHT FOR A LONG TIME THAT EUROPA WAS A GREAT POTENTIAL POSSIBILITY TO LOOK FOR LIFE. BECAUSE THERE'S A DEEP OCEAN THAT'S WARM AND WHAT WE'RE SEEING, THE DISCOLORED MATERIAL, ORGANIC MATERIAL, THERE'S AN OCEAN AND ORGANIC MATERIALS INSIDE OF A ICE-COVERED MOON. SO WE PLANNED FLY-BY MISSIONS OF EUROPA BUT THE GOAL EVENTUALLY WAS TO DRILL DOWN THROUGH THOSE KILOMETERS OF ICE AND GET DOWN TO THE OCEAN.IT WAS FIRST SEEN IN 2012, 2013, DOING SPECTROSCOPY, BUT THIS YEAR IN SEPTEMBER USING THE HUBBLE SPACE TELESCOPE BUT WHEN EUROPA PASSED IN FRONT OF JUPITER, YOU COULD LOOK AT THE AURORA OF -- OF EUROPA AND WHAT WAS SEEN WAS WHAT LOOKED LIKE PLUMES OF WATER AS IF IT HAD BEEN INFERRED TO EXIST FOUR YEARS AGO, THEY LOOKED AT MANY ORBITS AND THEY SEEM TO BE INTERMITTENT AND SHOOT 125-MILES UP.
TED SIMONS : HOLY SMOKES!

LAWRENCE KRAUSS: WHAT'S NEAT, IF THAT'S THE CASE, WE CAN SAMPLE THE WATER OF EUROPA WITHOUT DRILLING DOWN. WE CAN SEND A SPACECRAFT THROUGH THAT AND LOOK FOR ORGANIC MATERIALS, EVIDENCE OF LIFE. IT MIGHT BE A REALLY GOOD FIRST STEP.

TED: THE SIZE OF EUROPA COMPARED TO EARTH?

LAWRENCE KRAUSS : SMALLER.

TED: A LOT SMALLER.

LAWRENCE KRAUSS : A LOT SMALLER.

TED: BUT MORE WATER.

LAWRENCE KRAUSS : BUT MORE WATER IT'S SOLID WATER, THE EARTH ISN'T, IT'S ROCK. BASICALLY HUNDREDS OF KILOMETERS THICK OF WATER UNDER -- OF WATER, UNDERNEATH MAYBE 10 TO 15 KILOMETERS OF ICE. IT'S SMALLER AND THAT THE EARTH BUT BECAUSE ITS BASICALLY A BALL OF WATER SURROUNDED BY ICE, IT'S LIKE A BAKED ALASKA, IN THAT SENSE. IT'S MORE WATER THAN ALL OF THE OCEANS ON EARTH.

TED: WHAT DOES THAT TELL US ABOUT WHAT IS HAPPENING?

LAWRENCE KRAUSS: IT CONFIRMS WHAT WE ALREADY THOUGHT. THERE'S A LOT GOING ON. WE USED TO THINK THAT THESE THINGS WOULD JUST BE FROZEN OBJECTS. BECAUSE OF THE HEAT GENERATED BY THE TIDAL FORCE, THE INCREDIBLE GRAVITY OF JUPITER, IT'S CAUSING A LOT OF DISTURBANCES AND WE'VE SEEN WATER GEYSERS ON OTHER MOONS OF JUPITER AND SATURN.

TED: REALLY?

LAWRENCE KRAUSS: YEAH, WE HAVE. AND THERE'S INTERNAL HEAT BEING GENERATED THAT SOME OF THAT WATER IS PUSHED UP AND THE FACT THAT WE NOW SEE IT, EUROPA AND BEEN ABLE TO IMAGE IT AND GO 125-MILES OFF THE MOON, MEANS THAT AS I SAY FROM THE POINT OF VIEW OF LOOKING FOR THE INGREDIENTS OF LIFE IT'S INCREDIBLY EXCITING.

TED: IS THAT ONE OF THE PRIME PROSPECTS IN THE SOLAR SYSTEM?

LAWRENCE KRAUSS: FOR MANY PEOPLE THEY THOUGHT IT WAS APRIME PROSPECT FOR LIFE -- EUROPA WAS THE PRIME PROSPECT. MAYBE EVEN MORE INTERESTING THAN MARS.

TED: OK. THIS IS NOT DEALING WITH OUTER SPACES SO MUCH AS --

LAWRENCE KRAUSS : WE'RE GOING FROM THE OUTER REACHES OF COMETS TO EUROPA, COMING TO JUPITER AND NOW ON EARTH.

TED: NOW WE'RE ON EARTH AND GOODNESS KNOWS HOW MANY HUNDRED OF THOUSANDS OF YEARS AGO, THE IDEA THAT -- I SAW THIS ON NOVA BY THE WAY JUST RECENTLY

LAWRENCE KRAUSS: TELL ME WHAT YOU LEARNED.

TED: I CAN'T DIVULGE. WE THINK WE KNOW, ONE GROUP SAID WE'RE OUT OF HERE, IN AFRICA.

LAWRENCE KRAUSS : ALREADY LOOKING AT THE GENETIC MAKEUP OF HUMANS FROM THE VARIETY OF CIVILIZATIONS HERE ON EARTH TODAY. WE'VE ALREADY KNOWN THAT OUR BASIS IS IN AFRICA. EARLY MODERN HUMANS DEVELOPED AROUND 200,000 YEARS AGO PROBABLY IN SOUTHERN AFRICA. THAT'S BEEN KNOWN, THE QUESTION IS HOW AND WHEN DID THEY GO AND POPULATE THE REST OF THE WORLD. THERES BEEN A LOT OF SOMETIMES CONFLICTING EVIDENCE. WHILE WE KNOW THAT BY 50,000 YEARS AGO, HUMANS WERE IN EUROPE AND BASICALLY MAKING THE NEANDERTHALS EXTINCT AND MAYBE AUSTRALIA AND OTHER PLACES. THERE IS EVIDENCE THAT THERE WERE EARLIER WAVES OF PEOPLE COMING OUT. WHAT IS INTERESTING, THREE RECENT STUDIES HAVE LOOKED AT NOT JUST THE SMALL POPULATION BUT HUNDREDS OF INDIVIDUALS COMPLETELY LOOKING AT THEIR COMPLETE HUMAN GENOME FROM MANY DIFFERENT COUNTRIES AND DIFFERENT RACIAL BACKGROUNDS, HAVE -- ALL CONVERGED ON THE SAME IDEA. INDEPENDENT STUDIES DONE FOR INDEPENDENT PURPOSES THAT BASICALLY A SINGLE WAVE, YOU AND I DESCEND FROM A SINGLE WAVE OF HUMANS THAT LEFT AFRICA AROUND 50,000 YEARS AGO. THERE WERE OTHER GROUPS THAT PROBABLY LEFT EARLIER, BUT BECAME EXTINCT. THE MODERN HUMANS MAY HAVE KILLED THEM. AND IT'S INTERESTING, THERE HAVE BEEN FINDINGS LOOKING AT ABORIGINAL TRIBES IN AUSTRALIA AND OTHER PLACES THAT SUGGESTS THERE WERE -- EVIDENCE OF FAR OLDER GROUPS THAT HAD NO GENETIC RELATIONSHIP TO MODERN HUMANS NOW. YOU KNOW, EXCEPT THE ONES WHO COULD -- THE COMMON ANCESTORS, THAT MAY BE CAME OUT EARLIER AND WHAT WAS DISCOVERED IN ONE OF THE STUDIES AND ONLY ONE OUT OF THE THREE, IN THE ABORIGINALS IN AUSTRALIA SEEMED TO HAVE 2% OF THEIR DNA POTENTIALLY COMING FROM ONE OF THESE MUCH OLDER GROUPS THAT MAY HAVE ARRIVED. THERE WAS ONE WAVE, THERE WERE OTHER WAVES, BUT BASICALLY ALL OF US CAME FROM THAT WAVE THAT EMITTED FROM AFRICA THAT LEFT 50,000 YEARS AGO. WHY DID THEY LEAVE? PROBABLY CLIMATE VARIATIONS.

TED: AH!

LAWRENCE KRAUSS: AND THAT'S INTERESTING, BECAUSE IT MEANS THAT THEY MOVED AS THE CLIMATE CHANGED, AS THEIR HABITAT CHANGED AND FOOD CHANGED AND IT'S A LOCAL RELATIONSHIP WITH THAT. CURTIS MARION AT ASU, LEADS A GROUP THAT STUDIED A CAVE IN SOUTHERN AFRICA CONTINUOUSLY INHABITED OVER 100,000 YEARS BY EARLY HUMANS AS THE COAST RECEEDED 10 MILES BACK AS AND CLIMATE CHANGE AND THEIR FOOD CHANGED, AND TO PROMOTE SOMETHING IN A WEEK, OCTOBER 19TH, WE'RE GONNA HAVE AN EVENT, AN ORIGINS PROJECT, ON EXTINCTIONS AND LOVE AND INCONVENIENT TRUTH AND CURTIS WILL BE THERE TALKING ABOUT HOW IT'S POSSIBLE THAT YOU AND I AND EVERYONE EMERGED FROM THAT SMALL GROUP IN THAT CAVE WHICH MAY AT ONE POINT COULD HAVE BEEN 500 INDIVIDUALS.

TED: WOW!

LAWRENCE KRAUSS : WE WERE THAT CLOSE TO BEING EXTINCT AND WE'RE GOING TO HAVE A ELIZABETH COLBERT A PULITZER PRIZE WINNING AUTHOR SHE WROTE THE BOOK THE SIXTH EXTINCTION, AND WE'LL TALK ABOUT MODERN EXTINCTIONS AND EVERYTHING INBETWEEN. OCTOBER 19TH. BUT IF WE TALK ABOUT CLIMATE CHANGE, IT MAY HAVE DRIVEN THOSE PEOPLE OUT BECAUSE THIS IS OVER TENS OF THOUSANDS OF YEARS, AND THAT BRINGS US TO THE PRESENT.

TED: CAN YOU BRING US TO THE PRESENT QUICKLY. I KNOW YOU HAVE A CO2 THING.

LAWRENCE KRAUSS: EXACLTY I WAS SAY CO2 WE HAD A LANDMARK LAST THURSDAY, A MOMENT IN EARTH'S HISTORY THAT WAS VERY IMPORTANT, WE MONITOR CO2, SINCE THE 1950, STARTED BY CHARLES HEELING ON A MOUNTAINTOP IN HAWAII, VERY FRESH AIR COMING FROM THE PACIFIC AND FIRST STARTED TO NOTICE THAT CO2 WAS RISING, 315 PARTS PER MILLION. 800 -- UP TO 8,000 YEARS AGO, IT WAS -- IT WENT FROM 150 PARTS PER MILLION TO 280 PARTS PER MILLION. ALREADY IN THE 1950 WE PASSED 350 MILLION PARTS PER DAY. WE PASSED A MILESTONE LAST THURSDAY, WITH -- FOR THE FIRST TIME FOR A FULL DAY AND IT VARIES AS IT GOES UP AND DOWN, DEPENDING ON WHETHER THE TREES ARE OUT AND TAKE CARBON DIOXIDE, BUT FOR ONE FULL SINGLE DAY THE EARTH PASSED 400 PARTS PER MILLION. WHICH IS DREADFUL. THE CURRENT PARIS ACCORDS, THE RATE WE'RE GOING WE'RE GONNA GET THERE IN MAYBE 25 YEARS, THE EARTH IS NOW WHERE IT'S NEVER BEEN BEFORE, WE PASSED A MILESTONE THAT WE SHOULD HAVE NEVER PASSED. 400 PARTS PER MILLION, WHICH DIDN'T EXIST AT ANY TIME. RIGHT BACK TO THE EARLY MODERN HUMAN, BACK TO THREE MILLION YEARS, LAST THURSDAY WAS AN UNFORTUNATE MILESTONE THAT WE SHOULDN'T CE;EBRATE, WE SHOULD TRY AND USE AS A WAY IT GET BACK TO WHERE WE ONCE WERE.

TED: WE ONLY HAVE 30 SECONDS LEFT HERE, IS THERE NO TURNING BACK THEN?

LAWRENCE KRAUSS : WELL THERES NO TURNING BACK UNLESS WE FIGURE OUT HOW TO GET CARBON OUT OF THE ATMOSPHERE, WHAT WE CAN TRY AND DO IS MAKE IT STOP GETTING WORSE -- ATMOSPHERE, WE COULD CONSERVE AND USE RENEWABLE FUELS BUT THE CARBON WILL STAY THERE FOR ABOUT 600 TO A THOUSAND YEARS AND NO MATTER WHAT THE DEVELOPING COUNTRIES ARE DOING THE UNITED STATES AND THE DEVELOPING WORLD PUT MOST OF THE CARBON THAT'S THERE NOW. IF YOU BREAK IT, YOU'VE GOT TO FIX IT.

TED: ON THAT PLEASANT NOTE, THANKS FOR JOINING US. CAN'T WAIT TO BRING YOU BACK. [LAUGHTER]

LAWRENCE KRAUSS : NICE TO BE HERE.

TUESDAY ON "ARIZONA HORIZON," A SPECIAL ONE-HOUR DEBATE BETWEEN THE FIVE CANDIDATES RUNNING FOR THE THREE OPEN SEATS ON THE STATE CORPORATION COMMISSION. AN HOUR LONG DEBATE ON THE NEXT "ARIZONA HORIZON." AND A REMINDER JOIN US AT 7:00 P.M. TONIGHT FOR THE SPECIAL ELECTION 2016 DEBATE BETWEEN SENATOR JOHN MCCAIN AND HIS DEMOCRATIC CHALLENGER, ANN KIRKPATRICK. TONIGHT AT 7:00 RIGHT HERE ON ARIZONA PBS. THAT'S IT FOR NOW, I'M TED SIMONS. THANKS FOR JOINING US! YOU HAVE A GREAT EVENING!