saving hubble updateneil degrasse tyson: hi, i'm neil degrasse tyson, your host of nova sciencenow. here's a question i get asked a lot: "howmany astrophysicists does it take to change a light bulb?" well, depends on the circumstances.for instance, what if the light bulb is on a priceless crystal chandelier and you hadto change the light bulb wearing boxing gloves? and what if that chandelier is way up highand you have to stand on the top of a tall, rickety ladder to reach it? whoa! what if this intricate job must be performedin space?
these are just the sorts of challenges, alltogether, at once, facing astronauts on an important and risky mission. a team of specialistsprepares for emergency surgery, a risky procedure that will cost millions. luckily, this patient is a celebrity, withan excellent health plan—courtesy of the u.s. government—the hubble space telescope. the hubble is probably the best-known scientificinstrument ever. since 1990, it's brought us unprecedented views of the universe andrevolutionized astrophysics. matt mountain: twenty years ago, before thehubble flew, we didn't know how big the universe was or how old it was. now we do. we didn'tknow that black holes really existed. we now
know that black holes are everywhere. andthe hubble telescope was the first telescope to actually examine the composition of a worldaround another star. without the hubble, none of those things would have happened. neil degrasse tyson: but by last year, hubblewas in trouble. it was dying, and half its instruments, including the camera that tookthese pictures, were already dead. the only hope to save hubble was a shuttle mission,launched this past may. launch day, kennedy space center: within anhour from now, space shuttle atlantis will launch, carrying a crew of astronauts to repairand service the hubble telescope for the last time.
i'm not the only one here to witness thishistoric launch. there's a few thousand spectators, plus news media. this will be the most closelywatched shuttle mission in years, because of hubble's unprecedented popularity. images from the hubble telescope brought theuniverse into our collective backyard. there's nothing else like it in the history of science.so it's a bit emotional for me. i have friends and colleagues on the space shuttle atlantis.so, good luck, atlantis. godspeed. nasa space shuttle mission control: 8, 7,6...2, 1...liftoff of space shuttle atlantis. neil degrasse tyson: the climb to orbit takesjust over eight minutes. astronaut 1: vehicle rolling to heads up nowto get good communication.
neil degrasse tyson: once there, it will takethem two days to catch up to hubble. then the real work can begin. michael massimino (nasa astronaut): we'rein the middeck of space shuttle atlantis, with my buddy john grunsfeld over here. john grunsfeld: and our spacesuits are here.we're getting ready to go outside. michael massimino: so it's a busy day, andthings are just going to keep getting busier. neil degrasse tyson: it starts with grabbinghold of the telescope. astronaut 1: megan mcarthur now repositioningthe shuttle's robotic arm to align with the telescope.
nasa space shuttle mission control: houston,atlantis. hubble has arrived onboard atlantis. michael massimino: if you look out there,there's a telescope waiting for us to start working on it. neil degrasse tyson: the work will start tomorrow:five spacewalks, one per day. but the preparation began long ago; these five days have beenyears in the making. it all starts in 2006, when two teams of astronautspacewalkers are assigned to the job. john grunsfeld leads one team; he's been to hubbletwice before. john grunsfeld: the hubble was designed tobe serviced by people, to take things out, put things in, turn bolts, keep it running.
neil degrasse tyson: john's partner is drewfeustel. this will be his first flight. drew feustel: we kind of operate on a buddysystem. one person does the work, another person's handing off tools, providing support. neil degrasse tyson: on the second team ismike good, also making his first flight. michael good (nasa astronaut): hubble's donesome great things, and it's great to know that i'm going to get to go up and have achance to get up there and touch it, open the doors, get inside of it to work on it. neil degrasse tyson: leading the second teamis veteran spacewalker mike massimino. he worked with john grunsfeld on hubble, in 2002.
michael massimino (nasa astronaut): if wecan fix hubble, with its new capabilities, it's going to make some great discoveries. neil degrasse tyson: there's lots to do: replacebatteries, install a brand new camera, swap out gyros, remove old optics, install a newspectrograph, and more. mike massimino: generally, what we do is wecome up with a whole replacement for an instrument or for a piece of equipment. and even if somethinglittle is wrong with it, you don't mess with it, usually. you just pull it out and putthe whole new one in. neil degrasse tyson: that's exactly what drewfeustel and john grunsfeld are about to do on spacewalk number one:...
drew feustel: ready, john. let's do this. oh, this is fantastic. neil degrasse tyson: ...pull out the old widefield camera, and put in a new one. they'll loosen one bolt, remove the old camera... drew feustel: copy, john. neil degrasse tyson: ...insert the new camera,and re-tighten the bolt; one of the simplest jobs on the entire mission. but early on, there's a big problem. drew feustel: mass, i put in three attempts,and see no motion on the a-latch bolt.
michael massimino: copy. neil degrasse tyson: when drew feustel triesto loosen the bolt holding in the old camera, it refuses to budge. drew feustel: no turning. michael massimino: try it without a m.t.l.at all. nasa space shuttle mission control: nasa copythat. in that case, we're with removing the m.t.l. neil degrasse tyson: the m.t.l. is a multi-torquelimiter, a safety feature. it limits the force on the bolt to keep it from breaking.
with no m.t.l., there's a chance drew couldbreak the bolt, putting hubble in danger. drew feustel: how far can we go with this,and what are the implications if i break the bolt? john grunsfeld: if it breaks, then wide fieldstays in. nasa space shuttle mission control: what johnsaid is correct. drew feustel: thanks. neil degrasse tyson: if the bolt breaks, theold wide field camera is stuck in hubble forever. the replacement, a brand-new $130-million-dollarcamera, which took more than 10 years to build, will come back to earth, never to be used.
drew feustel: okay, here we go. i think igot it. it turned; it definitely turned. nasa space shuttle mission control: we copiedand saw that. that's great news. john grunsfeld: well, it's been in there for16 years, drew. drew feustel: it didn't want to come out. john grunsfeld: i guess it just decided tobe a recalcitrant teenager. nasa space shuttle mission control: and thewide field planetary camera 2 is clear of the structure of the telescope. michael massimino: that's awesome news, dan. neil degrasse tyson: in the end, john anddrew finish everything spacewalk number one
was supposed to get done. but it was a closecall that could have permanently crippled the telescope. the next day, spacewalkers mike massiminoand mike good also have problems. nasa space shuttle mission control: crew membersare an hour and a half behind the timeline at this point. neil degrasse tyson: the second spacewalkends up taking just under eight hours, one of the longest in nasa history. the first two days have not gone well. andthe hardest spacewalks are yet to come. tomorrow, john and drew will try to fix a broken instrumentthat can't be replaced: the advanced camera
for surveys, or acs, which died in 2007. it's a new kind of work no one's ever donebefore: actual repairs in space. chuck shaw (director, hubble servicing mission):instead of just replacing or adding components, we're actually going inside. it's more likeneurosurgery. neil degrasse tyson: to learn how they'lltry to do these repairs, months before launch i went to goddard space flight center, inmaryland. deputy program manager mike weiss took me through the world's largest cleanroom.every tool, part and new instrument going to hubble is kept here. in the heart of this super clean operatingroom, is a life-sized mockup of the patient:
the part of hubble containing the instruments.deep inside is a.c.s., the vital organ that's failed. it might look like a refrigerator,but this big black box is actually a precision digital camera. just like any digital camera, a.c.s. runsoff electronics. and that's what's died, the power supply. to fix it, 32 tiny screws haveto be removed, then a cover, then circuit boards have to come out. okay, so this would be the offending powersupply board? mike weiss: right. neil degrasse tyson: even though right nowit's just a smooth surface, i would see printed
circuitry here and... mike weiss: absolutely. neil degrasse tyson: ...components? mike weiss: and they're going to pull allfour of these boards out. neil degrasse tyson: so this seems easy enough.where's the challenge? mike weiss: the challenge is it was neverdesigned to be pulled out like that, with an astronaut wearing a glove, and it couldcompromise the glove. it could have sharp edges. neil degrasse tyson: "compromise the glove"is euphemism for me losing the pressurization
of my suit and dying? mike weiss: ultimately. neil degrasse tyson: danger is just one challenge.working while weightless is quite another. things like tools and loose screws will float.and if you're not strapped down, when you try to turn a screw, your body turns instead. and, ultimately, if just one of those 32 screwsthat has to be removed to fix the a.c.s. should float into hubble, it could trash the telescopeforever. so how are they going to get those screwsout safely? with a special contraption designed just for this mission: the fastener captureplate.
john grunsfeld: it's basically a panel thatis made out of a clear plastic and has holes in that you can put a screwdriver through. mike massimino: but small enough so that nothingwill come out. john grunsfeld: as a result, we can removeall those screws. they'll float around, but we won't lose any. and then we can take thecover plate off. neil degrasse tyson: to get a feel for whatit's like using the fastener capture plate, i decided to try it myself. mike weiss: you then need to turn three levers. neil degrasse tyson: three different screws.
mike weiss: one, two, and three differentlocations. neil degrasse tyson: there we go. in space, 32 screws have to come out. i figuredi'd try two. so i've got my miner's light into number 17. steady. there we go. i'm in.we are succeeding, i think. i am not succeeding. and i can't imagine doing this in a spacesuit. but doing it in a spacesuit is precisely whatjohn grunsfeld is facing on spacewalk number three. john grunsfeld: the fastener capture platewill be next. nasa space shuttle mission control: the fastenercapture plate now removed, having done its
job... neil degrasse tyson: but as the repair getsunderway... nasa space shuttle mission control: ...capturingthe 32 tiny screws. neil degrasse tyson: ...the one thing thatnobody expects is what actually happens: perfection. john grunsfeld: card one is out. nasa space shuttle mission control: nice. john grunsfeld: i heard that. neil degrasse tyson: no loose screws; no cutgloves. nasa space shuttle mission control: oh, that'sunbelievable!
neil degrasse tyson: the a.c.s. repair, probablythe toughest job on the whole mission, goes without a single hitch. down on the ground, the goddard engineerswho designed the tools and planned the repair are thrilled. nasa engineer 1: it was a good one today. mark jarosz (nasa engineer): no issues, aheadof the timeline, it went smooth, just like they practiced it. neil degrasse tyson: over the next two days,the final spacewalks complete every task assigned to the mission.
nasa space shuttle mission control: the finalspacewalk to service the hubble space telescope is complete. neil degrasse tyson: this mission hasn't justfixed hubble, it's set a new precedent for the level of intricate repair work that'spossible on spacewalks. matt mountain: we've pulled out boards, replacedboards, struggled with, you know, handles that wouldn't come off, and improvised. imean, i think we have raised the bar enormously, because suddenly you can see what humans cando in space. neil degrasse tyson: the day after the finalspacewalk, hubble is released back into its own orbit. it's the last time humans willever touch or see this magnificent science
instrument. michael massimino: what were you thinkingwhen you patted hubble goodbye? john grunsfeld: "happy voyages. i hope everythingthat we did worked." neil degrasse tyson: over the next few months,the new instruments get acclimated to the conditions of space. and i can't wait to seewhat a rejuvenated hubble can do. matt mountain: it's probably between 50 and100 times more powerful than it was when we first launched the hubble, so it's a completelynew telescope. neil degrasse tyson: just weeks ago, hubbletransmitted the first post-repair images. it's the start of a new era in hubble history,and later this fall, you can see those images
and watch the story of the whole mission onnova. gangster birdsneil degrasse tyson: you know, things can get tough out there in the animal kingdom.disagreements between species may arise; unpleasantries may occur; sometimes, steps must be takento ensure the survival of the family. but our expectations have been exceeded by oneparticular animal, who enforces its will in a manner heretofore seen only in humans. correspondent anna lee strachan has venturedinto the swamps to track down a creature that may be giving its neighbors an offer theycan't refuse. anna lee strachan: it may look peaceful, butthese quiet cow fields might be a cover for
a mob. you know the type from tv. marlon brando (as don vito corleone in thegodfather): i'm going to make him an offer he can't refuse. anna lee strachan: except this time, the goonsaren't human. jeff hoover is on the case. and we're on thetrail of one of the most sophisticated crime schemes in the animal world. al pacino (as tony montana in scarface): sayhello to my little friend. anna lee strachan: the suspect: the brown-headedcowbird.
if you've ever seen a cow, you've probablyseen a cowbird. the males are black with brown heads and the females are sort drab gray.until now, intelligence was never considered a trait because of a certain reputation. jeff hoover: people describe them as lazy.in general, people hate cowbirds. anna lee strachan: why? because cowbirds arefreeloaders. they never make nests or raise their own kids. they just ditch their eggsin other birds' nests, and let someone else do all the work. just ask any birdwatcher. bubba scales (birder): the cowbird chickstotally dominate the nest scene at the expense of the chicks that are supposed to be there.
courtney hooker (birder): you know, it's kindof sad to see a huge cowbird, and this tiny little songbird just running back and forthall day long trying to feed it, and the other chicks starve to death. anna lee strachan: in fact, cowbirds are sogood at what they do, they appear to be driving several songbird species to extinction. but things weren't always this way. it's partlyour fault. and it all started in the wild west. cowbirds used to roam with the buffalo,and only sneak eggs on species living close to open land. but now, with the bison goneand more manmade open land than ever before, we've invited cowbirds into every last cornerof the country, pushing dozens of already
troubled species to the brink. scott robinson: it's a pretty serious problem.without cowbird control, some of those populations, perhaps some of those species, would be extinctnow. anna lee strachan: and it gets worse. cowbirdscan somehow sucker over 150 different bird species to raise their offspring. how do theyget away with this? why don't the victims just throw those eggs out? that's where jeff hoover comes in. he's abird ecologist with the illinois natural history survey, and he thinks something in this storyjust doesn't add up. jeff hoover: there she goes. she just flewout.
for the longest time it's been thought thatcowbirds are either dumb or lazy, and they figured, "oh, all they do is that they comeand they lay their egg, and then they forget about it." anna lee strachan: they just ditch it? jeff hoover: they just ditch it, and theynever follow up. anna lee strachan: case closed. that is, untilhoover started studying one of the cowbird's local hosts, the prothonotary warbler. jeff hoover: we started seeing some reallyodd things happening. i would be watching a pair of warblers bringing food to a nest,and that nest contained a cowbird
baby, and i'd happen to notice, "oh, is thata female cowbird?" yeah, there's a female cowbird sitting maybe 50 feet away, kind ofhidden, and watching. and then i just kind of wrote that off, but then i saw it again. anna lee strachan: then hoover stumbled ona surprising twist. it happened when he started removing cowbird eggs from warbler nests inan effort to increase the number of warbler offspring. jeff hoover: and when we started doing that,we found that some of these nests were starting to have things happen to them. we'd see warblereggs disappear, warbler eggs get broken. the usual suspects would be a raccoon, snakes,flying squirrels, but they weren't a problem
before we started removing cowbird eggs. anna lee strachan: trashing nests? are wetalking about revenge? jeff hoover: we were in a little bit of denialbecause we didn't think that the cowbirds would be capable of this kind of sophisticatedbehavior. no one had really documented it before, and cowbirds have been studied a lot. anna lee strachan: we are talking about cowbirdshere, a.k.a., lazy bums who pal around with cattle all day. could cowbirds really be doingthis? to find out, hoover would need a scheme tocatch these culprits red-handed. and he knows just the place to start.
welcome to illinois swamp country, where cowbirdsget away with dumping over 4,000 eggs on warbler parents every year. so where are we headed? jeff hoover: we are headed to a site calledx swamp. anna lee strachan: like x files x swamp? jeff hoover: like x files. there aren't anyaliens here, but it's got about 20 pairs of the warblers that we're studying, and there'salso cowbirds here, so it fit the bill for what we needed. anna lee strachan: the game plan: first stakeout nesting sites across warbler territory.
jeff hoover: and maybe if i can take the polesfrom you.... and this looks like a really good spot to put up one of our nest boxes. anna lee strachan: right here? jeff hoover: right here. there. okay. so we'vegot our two poles and cardboard milk and juice cartons. anna lee strachan: next, we'll line up hundredsof carbon-copy nest boxes all over the swamp. so now we've got a nice little home here forthe warbler. jeff hoover: right, and if we left it outlike this they probably wouldn't use it. so we need to make it...
anna lee strachan: it looks a little suspicious,i have to say. jeff hoover: yes, yeah. we need to make itblend in a little better with the environment out here. anna lee strachan: but how do you keep othercritters like snakes and raccoons from butting in? so what's that? jeff hoover: so this is axle grease. it keepsthings like raccoons from being able to climb up and do anything with the nest. anna lee strachan: ah, so this is like predator-proofing?
jeff hoover: exactly. this is really importantfor us to be able to eliminate yet another one of the possible suspects for who's ransackingour warbler nests. anna lee strachan: so we've set the sceneand ruled out the usual suspects. but to pin any nest-trashing on the cowbird, we'll needto rule out the warblers too. they could be trashing their own nests, for all we know.and that calls for a little custom modification to the housing. oh, look at that. jeff hoover: there we go. anna lee strachan: perfect.
jeff hoover: yeah. so this is the wide opening,or the big opening that both the warblers and the cowbirds can fit through. anna lee strachan: okay. jeff hoover: what we're going to do next iswe're going to take this smaller drill bit, and the warblers, believe it or not, can stillfit through that size of an opening. anna lee strachan: it's tiny! jeff hoover: but female cowbirds are aboutthree times the size of the warbler; they can't. now we've got a cowbird-free nest box.
anna lee strachan: nice. it's convertible. jeff hoover: exactly. so we start with thelarge opening, because we want cowbirds to come in and lay their eggs in the nests. andthen we will remove cowbird eggs, and put this insert in. and if we put this insertin there, these nests should all be safe, because cowbirds can't come in. anna lee strachan: the plan? first start allthe boxes with big openings—that way cowbirds can get in and lay their eggs— jeff hoover: once the female warbler leaves,it's go time for the female cowbird. the cowbird comes stealthily, flies in, lays her in eggin about 10 seconds time and blasts off. and
she's done. anna lee strachan: —then take the cowbirdeggs out, and for half the boxes, put those inserts in. now these nests should all besafe. the others still have big openings, so ifthey're the only ones to get ransacked, we'll know who done it. leaving one last step: waiting. jeff hoover: head out this way. anna lee strachan: all right. so have youever made a cowbird egg omelet? jeff hoover: my guess is that it probablywouldn't taste too bad, especially with a little bit of tabasco sauce on it.
anna lee strachan: the stakeout begins: dozensof nests, day after day, the team slogs through the muck to check the status of the eggs. it takes months, but slowly a pattern beginsto emerge: only the nests with big openings are getting ransacked. jeff hoover: and over a number years, thepattern became really, really clear to us, that, you know, "oh my goodness! we've actuallygot experimental evidence that female cowbirds are really doing this stuff." anna lee strachan: sure enough, those small-holednests cowbirds couldn't fit into were 100 percent safe.
it's the most compelling experimental evidenceever of an animal, besides us, exacting a mafia-like retaliation. scott robinson: my first reaction was, "ohboy, they're way smarter than we thought." anna lee strachan: and they even caught thewhole thing on tape. with quick, sharp stabs, the female cowbird does the dirty deed. withinseconds, the entire warbler brood is destroyed. jeff hoover: we had really nailed it. butthen why would they destroy the contents of the nest? what does that do for the cowbird? anna lee strachan: perhaps it's a power playcowbirds use to force other species into accepting their offspring.
jeff hoover: because the warblers could learn,"if you don't play along with this game, if you don't raise my offspring, there's a penalty.and that penalty is that we're going to come back, and we're going to mess up your nest." scott robinson: we suddenly have to view thesebirds as much more sophisticated than we'd ever thought. that says some amazing thingsabout avian intelligence. anna lee strachan: so maybe it's time to reconsiderthe cowbird's reputation. jeff hoover: i think the word "debunked" isexactly what we've done. they come back and they monitor nests; they're actually seeingtheir offspring are being taken care of. what i really like about it is that it's the femalecowbirds, too. it's tina soprano instead of
tony soprano, in this case, with the cowbirds. anna lee strachan: nothing personal, it'sjust business. profile: alfredo quiã‘ones-hinojosaneil degrasse tyson: plenty of great scientists have made a mark even though they came from humble origins. albert einstein, when he was younger, was a patent clerk. dmitri mendeleev, inventor of the periodic table of elements, was a poor kid who hitchhiked thousands of miles across siberia just to go to college. in this episode's profile, we meet a brain researcher whose journey of discovery was rife with challenges of its own. it's early monday morning, and dr. alfredo quinones-hinojosa,
or dr q., as everyone calls him, slips into his lab coat, as routinely as mr. rogers puts on his sweater. alfredo quinones-hinojosa: all right. neil degrasse tyson: his day begins with aquick sprint through the lab to check on things, and, as always, a good wash. alfredo quinones-hinojosa: clean your hands.you can never clean your hands too much. neil degrasse tyson: the pace here is fastbecause lives hang in the balance, lives that could be lost to a dread disease that, sofar, has defied understanding. alfredo quinones-hinojosa: what we're tryingto understand in my laboratory is very simple. it's really not that complex. we're tryingto understand, how does brain cancer originate
and how does it spread? neil degrasse tyson: to answer those questions,dr. q. and his research team are looking at neural stem cells which are taken from humanbrain tissue. these cells have the ability to become different types of mature braincells. dr. q. thinks that in brain cancer, somethingmay go wrong with these cells, causing them to grow out of control and seed tumors thatare frequently malignant. alfredo quinones-hinojosa: certainly, if itis malignant brain cancer...virtually...almost no possibility of cure. neil degrasse tyson: if these cells are growingout of control, and if dr. q. and his team
can determine why, then maybe one day they'llbe able to stop or reverse the process, transforming brain cancer from a deadly disease to a chronicbut manageable condition. alfredo quinones-hinojosa: we are at the forefrontof understanding human tissue, human cells. neil degrasse tyson: it's hard to get humanbrain tissue to study, especially tissue from living patients. but dr. q. has a specialconnection. it turns out he has a close relationship with one of the country's top brain surgeonshere at johns hopkins, dr. alfredo quinones-hinojosa. alfredo quinones-hinojosa: good morning. ihave exciting news for you. neil degrasse tyson: when he's not in hislab, he's with his patients. alfredo quinones-hinojosa: a very, very benignmenangioma. yours was the size of a tennis
ball. but the mass is all the way...righthere. ah, look at you. you did cut your hair, huh?how are you? don (surgical patient): just fine. how areyou doctor? neil degrasse tyson: tomorrow, he will beoperating on don to remove a brain tumor, or lesion. alfredo quinones-hinojosa: this is the actualm.r.i. you can see the lesion right here. don: that whole u-shaped area? alfredo quinones-hinojosa: that whole u-shapedarea. don: well, i'd be lying to you, if i didn'tsay i was nervous.
alfredo quinones-hinojosa: yeah, of course. don: i know i'm in good hands. alfredo quinones-hinojosa: well, i promiseyou—this is what i always tell my patients—i promise you that my goal is to get you inand out safe. neil degrasse tyson: on the day of surgery,at the cashier's line at breakfast, he runs into don's sister and brother-in-law, whoasks him, in spanish, "are you ready?" alfredo quinones-hinojosa: listo. neil degrasse tyson: this isn't a day fortheory or larger questions. today, as he walks into the operating room, the scientist isa surgeon. it's a transformation that can
be seen in his eyes. alfredo quinones-hinojosa: no doubt at thatmoment, okay? there's no place for doubt at that moment. because that moment, when we'reabout to walk into the arena, into the operating theater, there's no place for mistakes andthere's no place for errors. and i tell them, specifically, when we go in, it's going tobe all positive energy. all that passion, all that training, everything that i havedone in my life to prepare for that specific moment is going to come out. and we're goingto go in together and we're going to take care of this. neil degrasse tyson: don's tumor, or lesion,is just millimeters from the part of don's
brain that controls his speech. dr. quinoneshas to keep don awake and talking to make sure that they don't damage his ability tospeak or make him mute, for life. alfredo quinones-hinojosa: alrighty, i wantdon's mouth to be a little bit moist. neil degrasse tyson: to be sure, they runa test first. as don counts, dr. quinones stimulates his brain to locate those areasthat determine speech. don: thirty, uuuuuhhhhhhh... various in o.r.: are you okay? don: yeah. thirty one, 32, 33, 34, 35, thi...uuuhhh... o.r. person: you're okay.
don: thirty six, 37, 38. alfredo quinones-hinojosa: i know, in my heart,that this is a tough fight. i know that the chances that i may have a significant impacton this disease are not very good. as a matter of fact, to be honest with you, the odds areoverwhelmingly against me succeeding in this field, as far as finding a cure or a betterway to treat brain cancer. but so were the chances of me sitting here with you today,when i came to this country, 20 years ago. neil degrasse tyson: chances were about allalfredo had in 1987, and they were slim to none. he was a mexican citizen, poor and desperateto come to america, when he jumped this fence and snuck into the country as an illegal alien.
alfredo quinones-hinojosa: it is tough tobe poor. it is tough to be poor in the united states; imagine how much more difficult itis to be poor in poor countries. and it's tough to survive in that environment, to behonest with you. i think that it was pretty clear to me that this is what i needed todo. neil degrasse tyson: alfredo grew up in mexicali,just across this wall, at the california border. neither of his parents made it past the firstgrade, the same grade little alfredo was in when he started managing the finances of hisfather's gas station. alfredo quinones-hinojosa: by the age of five,i was already working. by the age of 10, i was a major contributor.
neil degrasse tyson: what little the familyhad disappeared, along with the mexican economy, in the 1980s, and alfredo jumped the fenceat 19. he became a migrant worker in the san joaquin valley. alfredo quinones-hinojosa: at first, i wasthinking, i am going to take over the world with this. i am going to go back to my countrytriumphant, and i am going to be making a lot of money. then i get my first check, about$130 a week, and i realized this might take a little bit longer. this is hard work. neil degrasse tyson: he lived in this trailerfor about a year, all by himself. alfredo quinones-hinojosa: it was a palace.
neil degrasse tyson: alone and depressed,alfredo made it to stockton, where he shared a room with other family members and enrolledin english classes at san joaquin delta community college. there, he met anna. anna quinones: i kept seeing him walking acrossthis, like, little area, where everybody would sit and relax, and i would see him just flyby, very fast: shoo, shoo. neil degrasse tyson: they became friends,but didn't date for another two years. alfredo quinones-hinojosa: i just never...youknow, i never thought...i mean, it's my insecurities. how can this beautiful woman be interestedin a guy who has nothing? anna quinones: i saw something in him rightaway, that he was different. and i think that's
one of the reasons why i was attracted tohim, because i could see, like, the fire within him, that, you know, someday, somewhere, somethingfabulous was going to happen with him. neil degrasse tyson: alfredo kept moving quickly.from berkeley, he went to harvard medical school. he became a u.s. citizen; marriedanna; had three kids, a dog and a cat; did his residence and post doc at u.c. san francisco;and started his lab, and became a surgeon at johns hopkins. four hours into don's operation, dr. quinonesremoves the tumor, leaving don's speech intact. don has already agreed to give dr. q.'s labsamples of his brain's fluid and tissue from the tumor. and don, his brain open, and withdr. q.'s fingers literally inside of it, says...
don: take as much as you want. alfredo quinones-hinojosa: isn't that amazing?i can take his speech away just like that. just by going a millimeter over. by takinga small vessel, a microscopic vessel that you cannot even see, anything can change radically.and yet he said, "take as much as you want." neil degrasse tyson: don doesn't know thathe's just given his tissue to a research team full of hungry overachievers, who understandthat ending their week, every friday night, with a lab meeting to discuss their researchuntil 10:00 p.m., is just part of the price of working with dr. q. jason chang (student): i'm from san francisco.i went to university of california san francisco
medical school. student 1: ...sophomore at johns hopkins university. student 2: ...from mit. student 3: i'm from oxnard, california. student 4: ...ecuador. student 5: ...from india. student 6: ...wakefield, rhode island. neil degrasse tyson: dr. q. is sharing someof the amazing opportunity he's had. but he's also got a lab to run, and if he can't movefast enough to accomplish his dream, he's
hoping one of these young people will getthe chance. alfredo quinones-hinojosa: i have to recognizethat i may never be able to have a significant impact on brain cancer, so my duty is to trainthose future generations. neil degrasse tyson: in dr. q.'s version ofthe american dream, rigorous, sometimes endless work leads to more and bigger dreams. earlier that day, just two days after hissurgery, don went home—living proof of dr. q's american dream—living, to dream somemore. how memory worksneil degrasse tyson: most of us hold in our minds, memories of our lives, so vivid thatwhen we recall them, they seem real and indelible.
they're an essential part of who we are. butas we explore the mechanics of the brain, we're starting to learn exactly what thesememories are made of. and it turns out a lot of it boils down to chemistry. as correspondent chad cohen reports, researchersare discovering the precise molecules that can create memories, as well as the moleculesthat can erase them forever. chad cohen (correspondent): this is the brainthat, more than any other in history, has allowed scientists to make sense of your brain.for 82 years, it resided in the head of a man named henry gustav molaison, better knownas h.m. he was, perhaps, the most-studied patient ever. and that didn't end when hedied last year.
with h.m.'s permission, neuroanatomist jacopoannese went to work, dissecting his brain into 3,000 slices. jacopo annese (the brain observatory/universityof california, san diego): you can imagine the brain being like a book, and our tissueslices are the pages of this book. the only catch is that the slices are transparent.so you cannot really see anything until you use a lot of obscure chemical processes toreveal the features in the tissue. eventually, the entire book will be completely stained.and they will tell us the story of this brain. chad cohen: it's a story that begins withepilepsy, epilepsy so severe that by 1953, h.m. had reached his breaking point.
suzanne corkin (massachusetts institute oftechnology): he had to stop working because of the frequency of his seizures. it was justtoo dangerous. so he was basically at home with his parents. his life was on hold. chad cohen: in desperation, h.m. let surgeonwilliam scoville remove slivers of brain on either side of his head, each containing aseahorse-shaped structure called a hippocampus. this might have seemed reasonable at a timewhen we knew almost nothing about memory. and it did quiet his seizures, though at aterrible cost. suzanne corkin: do you know what you did yesterday? henry gustav molaison (epilepsly patient/filefootage): no, i don't.
suzanne corkin: how about this morning? henry molaison: that, i don't know myself.i can't tell you because i don't remember. chad cohen: h.m.'s condition might have seemedlike simple dementia, but as neuroscientist brenda milner discovered, it was anythingbut. brenda milner (montreal neurological institute):he would say, "right now it's like waking from a dream. right now everything is clear.but what happened just before?" chad cohen: milner found that h.m. had a normali.q. he could crack jokes, solve puzzles. even, to some extent, remember. eric kandel (columbia university): so h.m.could remember everything that happened prior
to the operation. he could remember the traumaof his childhood. he could remember going to elementary school, to high school, workingin the assembly plant. chad cohen: what he couldn't do was hold onto new information for more than a few minutes. in a moment of insight, milner concluded thehippocampus must make long-term memories out of short-term ones. suzanne corkin: that was a groundbreakingfinding because it showed that the ability to establish long-term memories is localizedto this tiny area in the brain. chad cohen: if h.m. had contributed nothingmore, his fame would have been assured. but he would go on inspiring discoveries for decades.the next involved a pencil, a mirror and,
again, brenda milner. eric kandel: she did this brilliant test inwhich she had h.m. draw the outlines of a star without looking at the star, but lookinginto a mirror. chad cohen: it's hard, at first, to draw withinthe lines, but could h.m., like people with normal memory, learn to do it with practice? after three days and 10 trials, his performancewas nearly perfect. brenda milner: well, he said, "i thought thiswould be difficult, but it looks as though i've done pretty well." he had no memory ofall these learning trials that he had been through, and the beautiful learning, thatwas the real contrast.
chad cohen: so h.m. could remember a motorskill, but not recall a fact or an event. it was a key discovery, because it showedthere were different kinds of memory, dependant on different parts of the brain. but what is a memory, anyway? nerve cells communicate by sending electricalsignals, which trigger the release of chemicals across tiny gaps called synapses. as one cellspeaks to another, chemical changes at the synapse make it easier for the signals topass. if only a few signals are sent, this transformation among a network of cells istemporary, resulting in a short-term memory. but if the signals keep coming, changes atthe most active synapses become permanent,
forming a long-term memory. eric kandel: so long-term memory actuallyinvolves an anatomical change in the brain. so, as i like to say, if you remember anythingabout this conversation tomorrow, it's because you will have a slightly different head thanyou had today. chad cohen: but what maintains a long-termmemory? how can you recall something that you may not have thought about for 20 years? neuroscientists todd sacktor and andre fentonthink the answer may lie in a molecule called pkmzeta that accumulates at synapses as memoriesform. andre fenton (suny, downstate medical center):pkmzeta acts as glue, if you will, for fixing
the connections amongst the neurons that wereactive together. so that later in time, those neurons are bound together and permanentlybound together, and can become active again to recall the experience. chad cohen: to assess the molecule's importance,fenton set up an experiment that would give the rat a memory. he placed it on a revolvingtable, where in one area it would receive a mild shock. andre fenton: there's the rat, and he's approachingthe shock zone. he's beginning to move a little bit but looks like he's going to enter theshock zone. he's gotten shocked, and he's just run away. he's approaching it right now.
chad cohen: soon, the rat always avoided theshock zone. andre fenton: so when the rat stays away froma particular area, we can imagine that he has remembered where he was shocked. chad cohen: then fenton injects the rat'shippocampus with a chemical called zip, known to undo the effect of pkmzeta. andre fenton: and what we observed, whichwas quite remarkable, was the rat acted as though it had forgotten completely where theshock zone was. and it explored the arena as if it was in the arena for the first time. just got shocked.
chad cohen: yet the rat could learn once againto avoid the shock zone. andre fenton: so we hadn't damaged the rat'sbrain. we hadn't broken its ability to learn anything. what we had simply done was specificallyerased the memory for that shock zone. chad cohen: without pkmzeta, the rat cannotmaintain a long-term memory. while this is not the only molecule active at synapses,it does appear we may have found a crucial ingredient of memory, one that explains howa three-pound lump of flesh can store, indefinitely, vivid recollections of everything from birthdaysto weddings, to episodes of nova sciencenow. meanwhile, the man who launched the modernera of brain research is making his final contribution. three thousand glass slidesof h.m.'s brain are being posted on the internet,
where researchers will be able to examinethem down to the level of individual neurons. and what would h.m. have thought about all this? henry molaison: the way i figure it is what they find out about me helps them tohelp other people.
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