"320 million miles from earth, a spacecraft is about to attempt the impossible." "Rosetta is going to catch a comet and send a lander onto its surface." "We're attempting something unparalleled in space flight." "It's got to be one of the most challenging missions" "I've ever been privileged to be involved with." "The comet is traveling at 41,000 miles per hour." "Every second, tons of gas, ice, and dust erupt from its surface." "Landing on this monster is a colossal undertaking." "We're gonna scratch and sniff the surface to get a real idea of what the comet is made of." "If successful, this mission could answer one of mankind's biggest questions" "How life began on earth." "By unlocking comets, we can really hope to unlock the whole story of the origin of the building blocks of life." ""To catch a comet" was made possible in part by contributions to your pbs station from..." "January 20, 2014." "As the sun rises over California," "NASA's giant, 230-foot deep space tracking station goldstone turns skyward." "Half a world away in Australia, the Canberra telescope rotates to the same point in the sky." "These two goliaths are among the most sensitive telecommunications antennae ever built." "Today they're part of a massive international effort to make contact with a spacecraft called rosetta." "Cinq, quatre, trois, deux, Un..." "Rosetta was launched over 10 years ago, its mission--to chase down and land on a comet." "In order to save power, it was put into hibernation nearly 3 years ago." "No one has heard from it since." "The telescope's data is streamed live to the European space agency's mission control in darmstadt, Germany." "The world's press has gathered here because today at 10 A.M., rosetta should wake up and begin the final phase of its daring mission." "30 years of planning," "$1.7 billion of investment, and the reputation of some of the world's most influential scientists and engineers hang in the balance." "Professor mark mccaughrean is one of the European space agency's most senior scientific figures and champion of their high-cost, high-risk mission to an alien world." "If rosetta doesn't wake up, we just don't have a mission." "We can as well go home and just start working on something else." "If it doesn't wake up today, we don't have anything." "Dr. Matt Taylor, project scientist." "He is in charge of the scientific instruments onboard rosetta." "It is a really big day today." "I'm feeling apprehensive but also pretty confident that we're gonna get rosetta back after 31 months of hibernation." "It was designed to do this, but there's always a little bit of apprehension when you're waiting." "Andrea accomazzo heads up rosetta's flight team." "He is ultimately responsible for getting rosetta to the comet safely." "Rosetta's last signal, received back in June 2011, placed it 341 million miles from earth." "Using the data, Andrea and his team predict that rosetta will have traveled another 450 million miles to an area near Jupiter's orbit." "This is where NASA's telescopes now point, but all they pick up are the background radio signals from that part of the sky." "Rosetta has been programmed to fire a radio pulse back to earth to verify that it is awake." "Its signal should create a spike above the background noise." "Finding rosetta is a massive challenge." "The spacecraft is but a tiny speck in infinite space." "Its core is no bigger than a family-sized SUV, its solar panels shorter than the length of two semi-trailer trucks, but inside this tightly packed bundle is a marvel of engineering, an automated laboratory full of scientific equipment and cameras" "and at its center, a washing-machine-sized lander called philae." "Rosetta is going to try and plant philae on one of the most enigmatic objects in space." "Comets are primordial city-sized boulders of ice and dust that roam the outer solar system beyond the planets, but sometimes one of these distant comets gets knocked off course and comes much closer to the sun." "As they do so, they put on an incredible display." "These are the comets we see in the night sky." "Rosetta will follow one of these icy travelers as it becomes active on its journey round the sun." "To get next to a comet and accompany this comet as it barrels into the inner solar system, that's difficult." "So that's a first." "This is the first time we have ever deployed a lander on a comet." "We're gonna scratch and sniff the surface to get a real idea of what the comet is made of." "Rosetta has got to be a 10 out of 10 in terms of the challenges that we face among the missions I've ever been involved with." "Rosetta presents a once-in-a-lifetime opportunity to answer some fundamental questions" "What are comets made of?" "What can they tell us about how our solar system evolved, and, most importantly, do they contain the essential ingredients of life?" "Comets are, more or less, unaltered since the birth of the solar system." "They've got water in them, dust in them, maybe even complex organic molecules, the origin of the building blocks of life." "But before rosetta can attempt to do all this, first, it has to wake up." "That should happen today." "It's been 8 hours." "The team expected rosetta to have made contact by now, but the radio telescopes still detect nothing but background noise." "Putting rosetta into hibernation was a huge risk, but the team had no choice." "In the run-up to rosetta's launch, a series of fatal flaws with the arianespace program grounded rosetta." "Its takeoff had to be delayed by over a year." "This meant rosetta had no chance of catching its original target." "The search was on for a new comet." "It needed to be large enough to land on and pass close enough to the earth for rosetta to reach it." "The scientists chose this one" "Comet 67p/churyumov-gerasimenko, a giant, 21/2-mile-wide pristine relic left over from the birth of the solar system" "But this comet had one major downside." "It was right on the limits of the distance rosetta could travel." "To reach it, rosetta would have to go 500 million miles from the sun, further than any other solar-powered spacecraft had ever gone before." "At this distance, her solar panels would no longer provide her with enough power." "Rosetta has some of the biggest solar panels ever put into space, but even those weren't big enough to operate the spacecraft safely when we were so far from the sun that the light intensity was only 4% of that which we get at the earth." "Faced with an impossible situation, the team came up with a bold plan." "To save power, they would put rosetta into hibernation." "It would mean shutting down almost all of rosetta's electronic systems, including her gyrostabilizer, the instrument that was keeping her pointing in the right direction." "One of the main things on board the spacecraft is the system that keeps it stable, and that takes too much power." "So we had to turn that off, but the problem with that immediately is that the spacecraft might start drifting away from the sun and not get any power anymore." "With no power, we can't run the critical heaters, and we need heaters inside the spacecraft to keep things like the fuel lines from freezing up because if they freeze up, we lose the mission completely." "The engineers needed to find a solution that would keep rosetta's solar panels faced towards the sun while in hibernation." "As you can see with this spinning top here, if you start spinning something, it's stable." "It stays in the same orientation all the time." "So that's exactly what we decided to do with the spacecraft." "On June 8, 2011, the flight team gave the go-ahead to put rosetta into a lateral spin." "Then it was shut down." "Only today will they find out if that solution worked." "It's 6:15 P.M., still no sign from rosetta." "The world's press is hungry for answers, but without contact from rosetta, the team is in the dark." "What is the latest?" "The delay could be because rosetta's antenna is not pointing in the right direction." "After more than two years of hibernation, rosetta might be pointing in a funky direction." "So when the spinning stops, she doesn't know where she is." "Rosetta has to work out where she is, figure out where the earth is, then point her antenna towards it." "In order to do that, she needs to open her electronic eyes." "Star trackers are little cameras which point out at the sky and take pictures of the stars and compare those stars to catalogs she holds on board." "From that, she can work out where she is." "Once she's locked on, she can point herself and the high-gain antenna at the earth and send that signal which we're all waiting for to say, "I'm awake."" "At mission control, there is news." "The goldstone telescope in California has detected a faint signal at rosetta's specific frequency, but in Australia, Canberra has detected nothing at all." "Then the signal disappears." "The signal returns." "This time, both telescopes pick it up." "Ha ha!" "Fantastic." "Yes." "Yes." "Ha ha!" "After nearly 3 years in hibernation, rosetta has come back to life." "Without today, we didn't have a mission, and now we have one of the most audacious missions ever made." "This it is." "It's the beginning for us." "The scientists, the operations crew got to get moving with the operations and do the science that we've been promising to do." "It's the beginning of an adventure." "The beginning of the beginning, yes." "Ha ha!" "In 10 months' time, rosetta will attempt to land philae onto churyumov-gerasimenko's surface." "Once there, she may be able to answer one of science's biggest mysteries." "Could comets have helped seed the earth with the ingredients of life?" "The countdown to the landing has begun." "January 21, 2014." "Rosetta is traveling through the outer reaches of the solar system," "5 million miles from comet churyumov-gerasimenko." "In the 10 years since launch, other space missions have transformed our understanding of comets." "In 2005, NASA's deep impact shot an 820-pound pod into comet temple one." "These are actual images of the collision." "The data from the impact revealed that comets aren't solid blocks of rock and ice, as was previously thought." "Instead, their composition is more like a giant ball of powdered snow..." "But a NASA probe called stardust was probably the most significant." "Oh, that's cool." "It's quite a trail." "Near spec has a great view." "In 2006, it returned to earth with a precious cargo of comet dust from the halo of a comet called wild two..." "All stations, the main chute is open." "We're coming down slowly." "But when scientists examined the samples, they found that many of the dust grains had fallen apart at the moment that stardust had caught them." "Unlike the dust in my house, which is like pebbles and really hard stuff, the stardust coming off of the comet is what we call friable." "It's literally like a piece of parchment that, when you crumple it, it flies into a million pieces." "Dr. Claudia Alexander is rosetta's project scientist heading up NASA's team." "In the last 8 years, NASA's scientists have been able to examine a few hundred comet dust grains collected from the stardust mission, and one of these grains revealed something extraordinary." "It contained an amino acid, one of the essential ingredients of life." "An amino acid, glycine, was among the material that was captured." "That's very exciting." "This is the first time we've seen amino acids associated with comets." "Amino acids are the building blocks of proteins." "They are necessary for all complex life." "The human body has maybe 20 of them, and they turn around, and they produce the proteins that make our bodies what they are." "It's likely that the primordial earth was too hot for these delicate molecules to form." "So for years, scientists have wondered how these intricate molecules came about." "Stardust's discovery raised the real possibility that comets may have helped seed the earth with amino acids" "3.8 billion years ago and set off the chain of events that led to the world we know today." "If the team is able to land on the comet and drill down beneath its surface, they may discover even more of these essential ingredients of life." "We definitely want, with the rosetta project, to find out if comets are the key." "It would add weight to the theory that comets may have helped deliver the building blocks of life to earth..." "But just getting rosetta into a position where it can land on philae is a gargantuan task." "The comet is traveling about 100,000 kilometers an hour." "That's a thousand times faster than a cannonball, and you imagine trying to land on a cannonball." "That's our challenge." "The safest way to land on the comet is to fly alongside it at the same speed..." "Instead of letting this comet whiz past us, we have to try and ride alongside it, and then we'll deploy the lander onto the surface and everything will be fine." "But no spacecraft has ever managed to match a comet's speed." "The problem goes like this." "To launch a spacecraft anywhere near a comet's speed demands vast amounts of fuel." "More fuel means more weight, and more weight means even more fuel." "It's the proverbial catch-22, making the entire thing unfeasible." "We would have had to use something like 20 tons of fuel on rosetta, and that would have meant a much bigger rocket to launch the whole thing into space in the first place." "That just wasn't possible." "So we had to think of something clever." "When rosetta launched, she didn't have enough speed to travel straight to the comet." "So she had to perform a series of special, speed-boosting maneuvers called gravity assists, or slingshots." "The first was around the earth." "Rosetta is flying along in her orbit around the sun, and the earth catches up from behind and grabs a hold of it with gravity." "The earth's powerful gravitational force caught hold of rosetta and hurled the craft out into space just like a stone in a slingshot." "It flings rosetta off at higher speed and on a new trajectory." "The earth's slingshot accelerated rosetta to 76,000 miles per hour, but this additional speed didn't come free." "Of course, for rosetta to get faster, the earth has to go a bit slower." "Rosetta's slingshot maneuver stole a tiny fraction of the earth's speed, making it slow down by less than a million millionths of a mile per hour." "The flight engineers coordinated another 3 rosetta slingshots" "Twice more around the earth and once around Mars." "Finally in 2011, rosetta was on target to catch up with churyumov-gerasimenko..." "The first spacecraft ever to match a comet's speed." "Right." "Well done." "Ha ha ha!" "Well done." "Rosetta is now just 1.2 million miles from churyumov-gerasimenko and will attempt to land on the comet in 187 days' time." "The flight team instructs rosetta to lock onto the comet." "Message received." "Rosetta's navigation cameras scan the heavens." "One tiny dot stands out." "This is churyumov-gerasimenko." "From this distance, churyumov-gerasimenko is nothing more than a blur." "The scientists must take a closer look." "They need to characterize the comet and spot potential hazards before rosetta goes into orbit around it." "This is it, the main phase of the mission." "Everyone has great anticipation for what's coming." "Matt's team has a suite of 11 instruments with which to unlock multiple aspects of this mysterious ball of rock and ice." "The flight team require this information before they can rendezvous with the comet and search for a suitable landing site." "We have no idea what this body even looks like." "We have no idea what its shape is." "We have no idea what its gravity is." "I don't know how we're gonna go into orbit without knowing those things in advance." "The scientists have just 4 months to establish churyumov-gerasimenko's shape, its mass, and its gravity, but data that comes through captures something else." "The comet has become active." "It has transformed into a violent, erupting mass of gas, dust, and ice." "This important discovery was made by rosetta's main science camera osiris." "Ok." "It's may." "We've started science operations." "The first thing that's come into range has been the osiris science camera, and we're starting to see our first view of the comet." "The camera has detected a sphere of dust and ice around churyumov-gerasimenko." "It's not anymore a pinprick." "It's a bit bigger than we expected, to be honest with you." "It's got this visible expanse around it, this shadow, this beginning of what we call a coma, an outer atmosphere." "The coma has taken rosetta's scientists by surprise." "In the outer solar system, a comet's surface should be completely frozen, but as it moves towards the sun, it heats up, and an extraordinary transformation occurs." "Geysers spew gases out of its surface, sending dust and ice into space, forming a visible halo around the comet called a coma." "The latest pictures show that this explosive activity has begun earlier than predicted." "Sending rosetta into this storm could be a huge challenge with great risk." "To build up a better picture of what rosetta's flight team is up against, rosetta's NASA project scientist." "Dr. Claudia Alexander and her team are recreating the closest thing to a coma on earth." "In this experiment, a miniature comet made of ordinary ice and dust is placed into a vacuum chamber." "The temperature is set to -190 degrees fahrenheit, and all the air is sucked out." "It's as if this scaled-down comet is in deep space just like churyumov-gerasimenko." "The simulation will demonstrate what's happening on the comet's surface." "Ok." "So, Lauren, are we ready?" "Yes." "It's ready to go." "Ok." "At first, the mini comet remains mostly dormant, but as the sun's heat intensifies, the comet experiences a sudden and explosive outburst." "Oh!" "There goes a good one, right there." "Massive jets of gas spew out of its surface in a process called sublimation." "Sublimation is where ice turns directly to gas without having any water involved." "So we all know what evaporation is." "Sublimation is when we go from a solid to a gas immediately." "When ice heats up in a vacuum, such as in space, it doesn't melt." "Instead, it's much more explosive." "And as this sublimating gas comes out, mostly at supersonic speeds, it carries with it the dust particles from the surface, and that is what causes a comet's coma to develop." "Osiris' data shows that comet churyumov-gerasimenko is in the early stages of forming a coma." "And we will see what has been done." "For Andrea and the flight team, this is a real cause for concern." "Rosetta's exceptionally long solar panels act like giant sails." "The comet's jets of gas currently stretch 800 miles into space, but they are likely to get much bigger." "Last time comet churyumov-gerasimenko orbited the sun in 2009, its coma extended hundreds of thousands of miles." "It will be bigger earlier." "Therefore, we have to try and get things done quicker." "The flight team plan to intercept the comet before its geysers grow too strong." "They will fire rosetta's thrusters for over 7 hours, one of the longest continuous burns ever attempted by a spacecraft." "How long is this sequence?" "They send instructions to rosetta." "Rosetta confirms its rockets have ignited." "The record burn pushes rosetta into the comet's path." "They will rendezvous in 3 months' time." "As rosetta nears the comet, the flight team get some good news." "Churyumov-gerasimenko's geyser activity has reduced." "The coma has died down." "To be honest with you, comets are unpredictable, and we don't know exactly what's going on at the moment." "No one knows why, but as the coma disperses, rosetta's scientific camera osiris is able to discern the shape of comet churyumov-gerasimenko's nucleus." "At first, it is too small to resolve..." "But then on July 14, 2014, rosetta sends back this startling image sequence." "Churyumov-gerasimenko looks like two comets that have smacked together." "It's an astonishing discovery." "98 days till touchdown, news of the comet's bizarre shape attracts press attention from around the world." "They gather at rosetta's mission control." "Today rosetta will rendezvous with comet 67p/churyumov-gerasimenko." "After traveling 4 billion miles, the flight team are about to bring rosetta into orbit just 62 miles above the comet." "Sylvain, say the famous words, please?" "We're at the comet!" "Yes!" "We have made history today." "We're in the same orbit as the comet around the sun." "So we've rendezvoused, first time ever, not bad." "Rosetta's camera now has a front-row view of one of the wonders of the solar system." "The comet's two massive heads are set 3 miles apart." "Its neckline is wider than two empire state buildings standing on top of each other." "Just look at this object." "It's astonishing." "You've got volcanoes." "You've got mountains." "You've got geysers." "Just the dynamic nature of this one object is really something." "We see cracks." "We see what looks like fissures." "These are, I think, brand-new types of features for a comet." "Here we have an object that clearly has potential to reveal ancient secrets." "We're at the threshold of learning, which is a great place to be." "How this unearthly object formed into such a bizarre shape is a mystery that Dr. Matt Taylor wants to solve." "There are two probable theories." "It could have been caused by two bodies colliding and sticking together, a contact binary, as it's known." "Well, you have to consider that there's quite a number of these objects out in space in the outer solar system." "They will mostly likely smack into each other at some point." "So that's one possibility of how this shape has come about, or it could have been a single comet eroded by sunlight." "Here, we're using the flame of this lighter to represent the heat from the sun." "If we consider that the comet could be made of different material in different places and some of that material is more reactive to sunlight, the central region may sublimate quicker than the rest of the comet and leave us" "with a very interesting shape like this." "September 2, 2014." "Rosetta's instruments detect faint jets." "These jets are focused in the middle section of the comet." "At the moment, the neck seems to be eroding faster than the heads, but the scientists will need to study the comet for months before they'll know whether it is two comets or if its strange shape was carved out" "by the heat from the sun." "The jets indicate something else." "The comet has become active again." "The flight team has to try and land on the comet before the jets grow too strong, but it's not only the jets that will make this landing difficult." "We've got boulders the size of a house." "We've got these massive, clifflike structures." "This is an alien ldscape, and if you wanted to choose a very alien landscape, this comet has got absolutely everything that you could ever consider to be alien." "You can see, this comet is quite a crazy shape." "I mean, not only is it double, but if you see in the pictures we have, there's structure all over it." "So it's a crazy, crazy comet to try and land on." "We've got to get down there." "So the first thing we have to do is pick a landing site." "To touch down successfully, the team need to find a safe landing spot." "For that, the flight team require detailed images of the comet's surface." "This is what rosetta's $100 million camera osiris is designed to do." "The osiris team is led by Dr. holger sierks." "Hi, carsten." "I'm here now." "So let's get going with the calibration today." "To help them operate osiris in space, they have an exact replica here on earth kept in a level 6 clean room at the Max planck institute in Germany." "Despite the camera's high cost, its resolution is relatively low by today's standards." "The number of megapixels we fly on rosetta is only 4." "10 years ago when osiris was built, a 4 megapixel camera was advanced." "Nowadays, many mobile phone cameras have a higher resolution." "To get the level of detail in the images that the landing team need, rosetta flies to within 20 miles of the comet's surface." "At this distance, a single mistake from the flight team could be catastrophic." "Over the next few days, osiris will take hundreds of detailed images in a bid to find a landing site on this jagged, Boulder-ridden comet." "Landing on a comet is completely different to landing on a planet or a moon." "The comet's gravitational pull is 100,000 times less than the earth's." "It's so weak that if you jumped off the surface of the comet, you would fly into outer space." "The weak gravity means rosetta can simply drop philae a few miles above the comet..." "Philae gets pushed out of the back of rosetta at a few centimeters a second, less than walking pace, and the very slight gravity of the comet will slowly pull philae down onto the surface." "It takes hours." "But the weak gravity presents a problem at touchdown." "So we're walking down to the surface of this comet, and we land, but it's not all over then because we'll bounce." "There's so little gravity on this comet that even at walking pace, he'll bounce off the surface, and we won't have succeeded." "So we've got to find a way of securing ourself to the surface." "Philae's designers spent years developing unique systems to stop philae rebounding off the comet and flying back into space." "Her 3 legs act like shock absorbers, cushioning the lander on impact." "Each foot is fitted with an ice screw." "The energy soaked up by the shock absorbers powers the ice screws which will drill 4 inches into the crust." "These plans were drawn up over 10 years ago." "At that time, most astronomers believed that a comet's surface was hard like ice, but a recent NASA comet mission and data from rosetta herself have revolutionized our understanding." "We used to think comets were dirty lumps of ice, but more recently, we've started to find that that's not the picture." "Now we've got closer to the comet, we can feel its gravity." "That gives us an idea of how much stuff it's got inside it, and it's not a block of ice." "So you can imagine this comet would be able to float on water." "That's the kind of density that we're talking about." "Light enough to float on water, but its weight is unevenly distributed." "Some parts may be very icelike." "We could also have areas that are more gravelly..." "Or even down to very dusty material, and once you consider the gravitational feel on the surface of the body itself is quite low, therefore, this kind of feel that I have prodding this material here would be totally different on the comet," "totally alien in that it'll be more like prodding a kind of gravel soup or a gravel cloud more than anything where this stuff is loosely bound by gravity." "The dusty, gravelly regions are not like anything we experience on earth." "If philae lands on one of these regions, then its ice screws may not work." "Luckily, philae has a backup plan" "Two copper beryllium harpoons which should secure philae onto the surface with tough kevlar cord, but these harpoons were also designed for ice." "Landing team leader Dr. Stephan ulamec wants to test the harpoons in granules of building insulation, perhaps the nearest thing to the ethereal gravel soup that can be produced in earth's gravity." "It will be very interesting to learn if the anchor harpoon" "Which is designed for ice, for more solid material" "Would also give us some anchoring for us on this very granular, very fluffy material." "The harpoons will be fired into large, wooden crates filled with this material." "The worst thing that could happen is, of course, that we pull out the harpoon when we want to tension the lander to the ground." "So it's interesting whether, although it's so soft, it gives enough resistivity that we can really tighten the lander to the surface, and this is part of the experiment we are doing right here." "Just like the harpoons on philae, a .01-ounce explosive propellant will detonate behind the spike, pushing it out of the chamber at a speed of 201 miles per hour." "Ok." "So let's do it." "Ok." "Let's do it." "Yeah." "If the harpoons don't hold, then the likelihood of philae securing itself onto the comet's surface will be greatly reduced." "3, 2, 1, 0." "The harpoon's cord is pulled back with a force of 15 Newtons." "That's about the same force as it would take to pull a venetian blind." "The harpoon isn't holding." "Then, dragged backwards by 4 inches, it sticks." "Yes!" "Ha ha ha!" "Well done." "Ja." "Wunderbar." "Right." "Thank you." "We're removing now with the vacuum cleaner the dust so we see the harpoon as it was when it actually anchored." "The reason for the harpoon's success-- 43-inch-long flukes that splayed out as the harpoon was dragged back through the loose material." "Adding these simple strips of metal to the harpoon's design could save philae's mission, but they'll only find out when they touchdown." "Rosetta has been chasing down churyumov-gerasimenko for over a decade." "It's traveled over 4 billion miles, spent nearly 3 years in deep space hibernation." "Now she's just 19 miles above the active comet." "So far, this mission has achieved everything it's set out to do..." "But the next phase will be the most ambitious operation that the European space agency has ever attempted." "They will try to plant a lander somewhere on this jagged, Boulder-ridden, double-headed comet." "We've got a very, very tricky landing from an engineering standpoint." "So any place we put it down is a good place on this particular comet." "September 13, 2014." "Scientists from across the world congregate in Toulouse, France, to choose a landing site." "This will not be an easy decision." "There's no smooth, flat area on that comet." "There are Boulder fields." "There are crevasses." "There are mountain ranges, cliffs." "It's all there to make our life difficult." "Rosetta's team has narrowed down the choice to 5 possible landing spots." "By the end of today, they must choose one." "Landing site "a" is on a ledge at the se of the comet, an area called the large head." "Having the lander here would be a very cool view." "To reach it, philae would have to skim over the small head and through some of the comet's jets." "The jets could push the lander off course, and philae could miss the comet entirely." "Site "a" is discarded." "Landing site "b" is in what looks like a crater on the end of the comet." "It's much easier to reach than "a," and it is relatively flat." "However, detailed images reveal a major drawback-- 329 boulders." "If half of this flat area is covered by boulders the size of a few meters, then this is completely risky, and it then reduces the chances of landing by about 50%." "If philae lands on a Boulder, it could tip over." "If that happens, it could lose radio communication with rosetta, and philae's mission would effectively be over." "Site "b" is rejected, and landing site "I" is rejected because it has rough terrain." "They're down to the last two." "Site "c" is on the side of the large head." "This landing zone may provide the best spot for most of philae's instruments." "The instruments are powered by solar panels, and this location is sunlight-rich." "Basically, your argument for "c"" "burns down to the energy question." "Over the 5 sites we had, "c" is, by far, the best." "The scientists in charge of philae's instruments like site "c," but the flight team who were in charge of landing philae are concerned." "This map shows the degree of sunlight the comet receives." "Areas permanently bathed in sunlight are red." "Some areas in site "c" are red." "In these areas, philae's solar panels could be exposed to sunlight for too long and become damaged." "The flight team prefer the final landing site-- "j."" "It is in a safer yellow zone, although there are some cliffs and 93 boulders, but some scientists continue to push for site "c."" "A good site is "c."" "Well, I would be very, very surprised if not "j" was the nominal." "No, no." "We discussed these two options." "Going to "c" would be energetically bad because it includes a very long descent time." "It's 4 hours." "In addition to points like that, the illumination angle is very bad." "In the end, the team agree on the safest option." "So the board has decided site "j" " "Surprise, surprise-- Is the nominal one, and site "c" as the backup." "For me, there was no one brilliant landing site." "We had to choose one that was the least bad out of all of them." "That's really all I can say about "j."" "It's risky." "It may not work, but we're gonna try our damnedest to make it work." "The risks may be high, but so, too, are the rewards." "If they manage to secure philae onto the comet's surface, then its suite of instruments can get to work." "Rolis will photograph the surface." "Concert will scan the comet's internal structure." "Sd2, a drill, will mine pristine comet material from 9 inches beneath the crust and then deliver a sample to one of the most important instruments of all" "A unique automated laboratory called cosac hidden inside philae's shell." "Cosac was built by Dr. Fred goesmann, at the Max planck institute in gottingen, Germany." "The lander looks a bit like a spider and has got eyes." "It's got feet, and cosac is the nose." "At its heart are 26 fingernail-sized ovens." "And this is what they look like, tiny, little devices." "Each oven will heat a sample to over 1,000 degrees fahrenheit, and then cosac will analyze the sample by sniffing the gases given off." "This could be a defining moment in science." "The team hope that cosac will find the special types of amino acids that are present in all living things, the so-called building blocks of life." "One could probably go as far as to say," ""well, Ok." "If comets contain this very amino acid," ""the one we use for life, why not postulate" ""that the comets seeded this very variant of amino acids that's used by biology?"" "They were a big bag of seeds." "They put it on earth, and that's where it grew from." "If these special amino acids are present, it will add weight to the theory that comets helped deliver these ingredients to the earth 3.8 billion years ago." "Philae will spend months looking for them..." "But first, rosetta must successfully land philae onto the surface of the comet." "Churyumov-gerasimenko's jets are growing stronger, and at any moment, they could erupt." "If there is a massive outburst, then we have to cope with that, and if that happens" "I hope it doesn't-- The coma is gonna start affecting the spacecraft." "Another concern is that rosetta might not release philae in exactly the right spot." "Rosetta's position is not that well-known to within, you know, a few hundred meters." "Obviously, if we don't know exactly where rosetta is, we can't then get the trajectory exactly right to get onto the surface." "If philae overshoots, it could land in a Boulder field." "Undershoot, and it could hit these deep crevasses." "Even if philae is on target, there is still a risk that it could hit one of the boulders in the landing zone, topple over, and not be able to complete its science mission." "But if this daring mission 300 million miles from earth achieves the seemingly impossible and secures its washing-machine-size lander onto the comet's surface, then this little spacecraft may answer one of mankind's biggest mysteries" "How life came to exist on earth." "We're attempting something unparalleled in space flight, something that not only talks about engineering and technology and risks, but has the potential for opening up whole new vistas of our understanding of where we came from." "We indeed do have a problem with the cold gas system aboard the lander, if indeed separation will take place." "We got the first go, the first go ahead with the landing sequence." "We're go for lander delivery and now we just have to wait." "We definitely confirmed that the lander is on the surface." "It worked flawlessly in the last minutes." "The lander is uh alone its on its own now." "And it worked perfectly well." "We got the first image taken during the descent." ""To catch a comet" was made possible in part by contributions to your pbs station from..." ""To catch a comet" is available on DVD." "To order, visit shop pbs." "Org or call 1-800-play-pbs."