[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.72,0:00:05.51,Default,,0000,0000,0000,,I'd like to take you on the epic quest\Nof the Rosetta spacecraft.
Dialogue: 0,0:00:05.51,0:00:09.54,Default,,0000,0000,0000,,To escort and land the probe on a comet,
Dialogue: 0,0:00:09.54,0:00:12.73,Default,,0000,0000,0000,,this has been my passion\Nfor the past two years.
Dialogue: 0,0:00:13.45,0:00:14.54,Default,,0000,0000,0000,,In order to do that,
Dialogue: 0,0:00:14.54,0:00:18.02,Default,,0000,0000,0000,,I need to explain to you something\Nabout the origin of the solar system.
Dialogue: 0,0:00:18.02,0:00:20.24,Default,,0000,0000,0000,,When we go back\Nfour and a half billion years,
Dialogue: 0,0:00:20.24,0:00:21.96,Default,,0000,0000,0000,,there was a cloud of gas and dust.
Dialogue: 0,0:00:21.96,0:00:26.48,Default,,0000,0000,0000,,In the center of this cloud,\Nour sun formed and ignited.
Dialogue: 0,0:00:26.48,0:00:32.20,Default,,0000,0000,0000,,Along with that, what we now know\Nas planets, comets and asteroids formed.
Dialogue: 0,0:00:32.20,0:00:35.61,Default,,0000,0000,0000,,What then happened, according to theory,
Dialogue: 0,0:00:35.61,0:00:39.62,Default,,0000,0000,0000,,is that when the Earth had cooled down\Na bit after its formation,
Dialogue: 0,0:00:39.62,0:00:44.40,Default,,0000,0000,0000,,comets massively impacted the Earth\Nand delivered water to Earth.
Dialogue: 0,0:00:45.08,0:00:49.52,Default,,0000,0000,0000,,They probably also delivered\Ncomplex organic material to Earth,
Dialogue: 0,0:00:49.52,0:00:52.91,Default,,0000,0000,0000,,and that may have bootstrapped\Nthe emergence of life.
Dialogue: 0,0:00:52.91,0:00:56.37,Default,,0000,0000,0000,,You can compare this to having\Nto solve a 250-piece puzzle
Dialogue: 0,0:00:56.37,0:00:59.57,Default,,0000,0000,0000,,and not a 2,000-piece puzzle.
Dialogue: 0,0:00:59.57,0:01:03.05,Default,,0000,0000,0000,,Afterwards, the big planets\Nlike Jupiter and Saturn,
Dialogue: 0,0:01:03.05,0:01:05.63,Default,,0000,0000,0000,,they were not in their place\Nwhere they are now,
Dialogue: 0,0:01:05.63,0:01:08.28,Default,,0000,0000,0000,,and they interacted gravitationally,
Dialogue: 0,0:01:08.28,0:01:11.83,Default,,0000,0000,0000,,and they swept the whole interior\Nof the solar system clean,
Dialogue: 0,0:01:11.83,0:01:13.43,Default,,0000,0000,0000,,and what we now know as comets
Dialogue: 0,0:01:13.43,0:01:15.54,Default,,0000,0000,0000,,ended up in something\Ncalled the Kuiper Belt,
Dialogue: 0,0:01:15.54,0:01:19.21,Default,,0000,0000,0000,,which is a belt of objects\Nbeyond the orbit of Neptune.
Dialogue: 0,0:01:19.21,0:01:22.91,Default,,0000,0000,0000,,And sometimes these objects\Nrun into each other,
Dialogue: 0,0:01:22.91,0:01:25.97,Default,,0000,0000,0000,,and they gravitationally deflect,
Dialogue: 0,0:01:25.97,0:01:30.43,Default,,0000,0000,0000,,and then the gravity of Jupiter\Npulls them back into the solar system.
Dialogue: 0,0:01:30.43,0:01:34.12,Default,,0000,0000,0000,,And they then become the comets\Nas we see them in the sky.
Dialogue: 0,0:01:34.12,0:01:37.39,Default,,0000,0000,0000,,The important thing here to note\Nis that in the meantime,
Dialogue: 0,0:01:37.39,0:01:39.69,Default,,0000,0000,0000,,the four and a half billion years,
Dialogue: 0,0:01:39.69,0:01:42.88,Default,,0000,0000,0000,,these comets have been sitting\Non the outside of the solar system,
Dialogue: 0,0:01:42.88,0:01:44.29,Default,,0000,0000,0000,,and haven't changed --
Dialogue: 0,0:01:44.29,0:01:47.19,Default,,0000,0000,0000,,deep, frozen versions of our solar system.
Dialogue: 0,0:01:47.19,0:01:49.28,Default,,0000,0000,0000,,In the sky, they look like this.
Dialogue: 0,0:01:49.28,0:01:51.23,Default,,0000,0000,0000,,We know them for their tails.
Dialogue: 0,0:01:51.23,0:01:52.90,Default,,0000,0000,0000,,There are actually two tails.
Dialogue: 0,0:01:52.90,0:01:56.76,Default,,0000,0000,0000,,One is a dust tail,\Nwhich is blown away by the solar wind.
Dialogue: 0,0:01:56.76,0:02:00.40,Default,,0000,0000,0000,,The other one is an ion tail,\Nwhich is charged particles,
Dialogue: 0,0:02:00.40,0:02:03.14,Default,,0000,0000,0000,,and they follow the magnetic field\Nin the solar system.
Dialogue: 0,0:02:03.14,0:02:04.29,Default,,0000,0000,0000,,There's the coma,
Dialogue: 0,0:02:04.29,0:02:07.20,Default,,0000,0000,0000,,and then there is the nucleus,\Nwhich here is too small to see,
Dialogue: 0,0:02:07.20,0:02:09.69,Default,,0000,0000,0000,,and you have to remember\Nthat in the case of Rosetta,
Dialogue: 0,0:02:09.69,0:02:11.87,Default,,0000,0000,0000,,the spacecraft is in that center pixel.
Dialogue: 0,0:02:11.87,0:02:15.98,Default,,0000,0000,0000,,We are only 20, 30, 40 kilometers\Naway from the comet.
Dialogue: 0,0:02:15.98,0:02:18.30,Default,,0000,0000,0000,,So what's important to remember?
Dialogue: 0,0:02:18.30,0:02:23.17,Default,,0000,0000,0000,,Comets contain the original material\Nfrom which our solar system was formed,
Dialogue: 0,0:02:23.17,0:02:25.53,Default,,0000,0000,0000,,so they're ideal to study the components
Dialogue: 0,0:02:25.53,0:02:29.79,Default,,0000,0000,0000,,that were present at the time \Nwhen Earth, and life, started.
Dialogue: 0,0:02:29.79,0:02:31.67,Default,,0000,0000,0000,,Comets are also suspected
Dialogue: 0,0:02:31.67,0:02:35.94,Default,,0000,0000,0000,,of having brought the elements\Nwhich may have bootstrapped life.
Dialogue: 0,0:02:35.94,0:02:40.31,Default,,0000,0000,0000,,In 1983, ESA set up\Nits long-term Horizon 2000 program,
Dialogue: 0,0:02:40.31,0:02:44.23,Default,,0000,0000,0000,,which contained one cornerstone,\Nwhich would be a mission to a comet.
Dialogue: 0,0:02:44.23,0:02:49.12,Default,,0000,0000,0000,,In parallel, a small mission to a comet,\Nwhat you see here, Giotto, was launched,
Dialogue: 0,0:02:49.12,0:02:55.33,Default,,0000,0000,0000,,and in 1986, flew by the comet of Halley\Nwith an armada of other spacecraft.
Dialogue: 0,0:02:55.33,0:02:58.90,Default,,0000,0000,0000,,From the results of that mission,\Nit became immediately clear
Dialogue: 0,0:02:58.90,0:03:04.09,Default,,0000,0000,0000,,that comets were ideal bodies to study\Nto understand our solar system.
Dialogue: 0,0:03:04.09,0:03:08.60,Default,,0000,0000,0000,,And thus, the Rosetta mission\Nwas approved in 1993,
Dialogue: 0,0:03:08.60,0:03:12.23,Default,,0000,0000,0000,,and originally it was supposed\Nto be launched in 2003,
Dialogue: 0,0:03:12.23,0:03:14.86,Default,,0000,0000,0000,,but a problem arose\Nwith an Ariane rocket.
Dialogue: 0,0:03:14.86,0:03:17.92,Default,,0000,0000,0000,,However, our P.R. department,\Nin its enthusiasm,
Dialogue: 0,0:03:17.92,0:03:20.14,Default,,0000,0000,0000,,had already made\N1,000 Delft Blue plates
Dialogue: 0,0:03:20.14,0:03:22.54,Default,,0000,0000,0000,,with the name of the wrong comets.
Dialogue: 0,0:03:22.54,0:03:26.10,Default,,0000,0000,0000,,So I've never had to buy any china since.\NThat's the positive part.
Dialogue: 0,0:03:26.10,0:03:27.82,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:03:27.82,0:03:29.70,Default,,0000,0000,0000,,Once the whole problem was solved,
Dialogue: 0,0:03:29.70,0:03:32.88,Default,,0000,0000,0000,,we left Earth in 2004
Dialogue: 0,0:03:32.88,0:03:35.97,Default,,0000,0000,0000,,to the newly selected comet,\NChuryumov-Gerasimenko.
Dialogue: 0,0:03:35.97,0:03:38.83,Default,,0000,0000,0000,,This comet had to be specially selected
Dialogue: 0,0:03:38.83,0:03:41.48,Default,,0000,0000,0000,,because A, you have to\Nbe able to get to it,
Dialogue: 0,0:03:41.48,0:03:44.26,Default,,0000,0000,0000,,and B, it shouldn't have been\Nin the solar system too long.
Dialogue: 0,0:03:44.26,0:03:48.21,Default,,0000,0000,0000,,This particular comet has been \Nin the solar system since 1959.
Dialogue: 0,0:03:48.21,0:03:51.52,Default,,0000,0000,0000,,That's the first time\Nwhen it was deflected by Jupiter,
Dialogue: 0,0:03:51.52,0:03:54.50,Default,,0000,0000,0000,,and it got close enough\Nto the sun to start changing.
Dialogue: 0,0:03:54.50,0:03:56.15,Default,,0000,0000,0000,,So it's a very fresh comet.
Dialogue: 0,0:03:56.61,0:03:59.50,Default,,0000,0000,0000,,Rosetta made a few historic firsts.
Dialogue: 0,0:03:59.50,0:04:02.02,Default,,0000,0000,0000,,It's the first satellite to orbit a comet,
Dialogue: 0,0:04:02.02,0:04:05.64,Default,,0000,0000,0000,,and to escort it throughout\Nits whole tour through the solar system --
Dialogue: 0,0:04:05.64,0:04:08.94,Default,,0000,0000,0000,,closest approach to the sun,\Nas we will see in August,
Dialogue: 0,0:04:08.94,0:04:11.26,Default,,0000,0000,0000,,and then away again to the exterior.
Dialogue: 0,0:04:11.26,0:04:13.86,Default,,0000,0000,0000,,It's the first ever landing on a comet.
Dialogue: 0,0:04:13.86,0:04:17.55,Default,,0000,0000,0000,,We actually orbit the comet\Nusing something which is not
Dialogue: 0,0:04:17.55,0:04:19.00,Default,,0000,0000,0000,,normally done with spacecraft.
Dialogue: 0,0:04:19.00,0:04:22.64,Default,,0000,0000,0000,,Normally, you look at the sky and you know\Nwhere you point and where you are.
Dialogue: 0,0:04:22.64,0:04:24.77,Default,,0000,0000,0000,,In this case, that's not enough.
Dialogue: 0,0:04:24.77,0:04:28.07,Default,,0000,0000,0000,,We navigated by looking\Nat landmarks on the comet.
Dialogue: 0,0:04:28.07,0:04:30.54,Default,,0000,0000,0000,,We recognized features --\Nboulders, craters --
Dialogue: 0,0:04:30.54,0:04:34.56,Default,,0000,0000,0000,,and that's how we know where we are\Nrespective to the comet.
Dialogue: 0,0:04:34.56,0:04:39.09,Default,,0000,0000,0000,,And, of course, it's the first satellite\Nto go beyond the orbit of Jupiter
Dialogue: 0,0:04:39.09,0:04:40.29,Default,,0000,0000,0000,,on solar cells.
Dialogue: 0,0:04:40.29,0:04:42.62,Default,,0000,0000,0000,,Now, this sounds more heroic\Nthan it actually is,
Dialogue: 0,0:04:42.62,0:04:47.72,Default,,0000,0000,0000,,because the technology\Nto use radio isotope thermal generators
Dialogue: 0,0:04:47.72,0:04:51.01,Default,,0000,0000,0000,,wasn't available in Europe at that time,\Nso there was no choice.
Dialogue: 0,0:04:51.01,0:04:52.59,Default,,0000,0000,0000,,But these solar arrays are big.
Dialogue: 0,0:04:52.59,0:04:55.86,Default,,0000,0000,0000,,This is one wing, and these are not\Nspecially selected small people.
Dialogue: 0,0:04:55.86,0:04:57.70,Default,,0000,0000,0000,,They're just like you and me.
Dialogue: 0,0:04:57.70,0:05:00.09,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:05:00.09,0:05:04.29,Default,,0000,0000,0000,,We have two of these wings,\N65 square meters.
Dialogue: 0,0:05:04.29,0:05:07.31,Default,,0000,0000,0000,,Now later on, of course,\Nwhen we got to the comet,
Dialogue: 0,0:05:07.31,0:05:10.84,Default,,0000,0000,0000,,you find out that 65 square meters of sail
Dialogue: 0,0:05:10.84,0:05:16.48,Default,,0000,0000,0000,,close to a body which is outgassing\Nis not always a very handy choice.
Dialogue: 0,0:05:16.48,0:05:18.52,Default,,0000,0000,0000,,Now, how did we get to the comet?
Dialogue: 0,0:05:18.52,0:05:22.19,Default,,0000,0000,0000,,Because we had to go there\Nfor the Rosetta scientific objectives
Dialogue: 0,0:05:22.19,0:05:26.00,Default,,0000,0000,0000,,very far away -- four times the distance\Nof the Earth to the sun --
Dialogue: 0,0:05:26.00,0:05:30.11,Default,,0000,0000,0000,,and also at a much higher velocity\Nthan we could achieve with fuel,
Dialogue: 0,0:05:30.11,0:05:34.43,Default,,0000,0000,0000,,because we'd have to take six times as\Nmuch fuel as the whole spacecraft weighed.
Dialogue: 0,0:05:34.43,0:05:35.84,Default,,0000,0000,0000,,So what do you do?
Dialogue: 0,0:05:35.84,0:05:39.32,Default,,0000,0000,0000,,You use gravitational flybys, slingshots,
Dialogue: 0,0:05:39.32,0:05:42.69,Default,,0000,0000,0000,,where you pass by a planet\Nat very low altitude,
Dialogue: 0,0:05:42.69,0:05:44.46,Default,,0000,0000,0000,,a few thousand kilometers,
Dialogue: 0,0:05:44.46,0:05:49.17,Default,,0000,0000,0000,,and then you get the velocity\Nof that planet around the sun for free.
Dialogue: 0,0:05:49.17,0:05:51.21,Default,,0000,0000,0000,,We did that a few times.
Dialogue: 0,0:05:51.21,0:05:53.69,Default,,0000,0000,0000,,We did Earth, we did Mars,\Nwe did twice Earth again,
Dialogue: 0,0:05:53.69,0:05:57.66,Default,,0000,0000,0000,,and we also flew by two asteroids,\NLutetia and Steins.
Dialogue: 0,0:05:58.32,0:06:02.98,Default,,0000,0000,0000,,Then in 2011, we got so far from the sun\Nthat if the spacecraft got into trouble,
Dialogue: 0,0:06:02.98,0:06:06.79,Default,,0000,0000,0000,,we couldn't actually\Nsave the spacecraft anymore,
Dialogue: 0,0:06:06.79,0:06:08.76,Default,,0000,0000,0000,,so we went into hibernation.
Dialogue: 0,0:06:08.76,0:06:12.10,Default,,0000,0000,0000,,Everything was switched off\Nexcept for one clock.
Dialogue: 0,0:06:12.10,0:06:15.61,Default,,0000,0000,0000,,Here you see in white the trajectory,\Nand the way this works.
Dialogue: 0,0:06:15.61,0:06:18.06,Default,,0000,0000,0000,,You see that from\Nthe circle where we started,
Dialogue: 0,0:06:18.06,0:06:21.87,Default,,0000,0000,0000,,the white line, actually you get\Nmore and more and more elliptical,
Dialogue: 0,0:06:21.87,0:06:24.82,Default,,0000,0000,0000,,and then finally we approached the comet
Dialogue: 0,0:06:24.82,0:06:29.19,Default,,0000,0000,0000,,in May 2014, and we had to start\Ndoing the rendezvous maneuvers.
Dialogue: 0,0:06:29.19,0:06:33.78,Default,,0000,0000,0000,,On the way there, we flew by Earth and we\Ntook a few pictures to test our cameras.
Dialogue: 0,0:06:33.78,0:06:35.96,Default,,0000,0000,0000,,This is the moon rising over Earth,
Dialogue: 0,0:06:35.96,0:06:37.92,Default,,0000,0000,0000,,and this is what we now call a selfie,
Dialogue: 0,0:06:37.92,0:06:41.61,Default,,0000,0000,0000,,which at that time, by the way,\Nthat word didn't exist. (Laughter)
Dialogue: 0,0:06:41.61,0:06:44.58,Default,,0000,0000,0000,,It's at Mars. It was taken\Nby the CIVA camera.
Dialogue: 0,0:06:44.58,0:06:46.76,Default,,0000,0000,0000,,That's one of the cameras on the lander,
Dialogue: 0,0:06:46.76,0:06:49.18,Default,,0000,0000,0000,,and it just looks under the solar arrays,
Dialogue: 0,0:06:49.18,0:06:53.45,Default,,0000,0000,0000,,and you see the planet Mars\Nand the solar array in the distance.
Dialogue: 0,0:06:53.45,0:06:59.12,Default,,0000,0000,0000,,Now, when we got out\Nof hibernation in January 2014,
Dialogue: 0,0:06:59.12,0:07:00.90,Default,,0000,0000,0000,,we started arriving at a distance
Dialogue: 0,0:07:00.90,0:07:03.74,Default,,0000,0000,0000,,of two million kilometers\Nfrom the comet in May.
Dialogue: 0,0:07:03.74,0:07:07.84,Default,,0000,0000,0000,,However, the velocity\Nthe spacecraft had was much too fast.
Dialogue: 0,0:07:07.84,0:07:13.91,Default,,0000,0000,0000,,We were going 2,800 kilometers an hour\Nfaster than the comet, so we had to brake.
Dialogue: 0,0:07:13.91,0:07:15.76,Default,,0000,0000,0000,,We had to do eight maneuvers,
Dialogue: 0,0:07:15.76,0:07:18.34,Default,,0000,0000,0000,,and you see here,\Nsome of them were really big.
Dialogue: 0,0:07:18.34,0:07:24.36,Default,,0000,0000,0000,,We had to brake the first one\Nby a few hundred kilometers per hour,
Dialogue: 0,0:07:24.36,0:07:28.67,Default,,0000,0000,0000,,and actually, the duration of that\Nwas seven hours,
Dialogue: 0,0:07:28.67,0:07:31.62,Default,,0000,0000,0000,,and it used 218 kilos of fuel,
Dialogue: 0,0:07:31.62,0:07:35.57,Default,,0000,0000,0000,,and those were seven nerve-wracking \Nhours, because in 2007,
Dialogue: 0,0:07:35.57,0:07:38.76,Default,,0000,0000,0000,,there was a leak in the system\Nof the propulsion of Rosetta,
Dialogue: 0,0:07:38.76,0:07:40.91,Default,,0000,0000,0000,,and we had to close off a branch,
Dialogue: 0,0:07:40.91,0:07:43.49,Default,,0000,0000,0000,,so the system was actually\Noperating at a pressure
Dialogue: 0,0:07:43.49,0:07:46.78,Default,,0000,0000,0000,,which it was never designed\Nor qualified for.
Dialogue: 0,0:07:47.80,0:07:52.70,Default,,0000,0000,0000,,Then we got in the vicinity of the comet,\Nand these were the first pictures we saw.
Dialogue: 0,0:07:52.70,0:07:55.28,Default,,0000,0000,0000,,The true comet rotation period\Nis 12 and a half hours,
Dialogue: 0,0:07:55.28,0:07:57.37,Default,,0000,0000,0000,,so this is accelerated,
Dialogue: 0,0:07:57.37,0:08:00.62,Default,,0000,0000,0000,,but you will understand that\Nour flight dynamics engineers thought,
Dialogue: 0,0:08:00.62,0:08:04.47,Default,,0000,0000,0000,,this is not going to be\Nan easy thing to land on.
Dialogue: 0,0:08:04.47,0:08:09.12,Default,,0000,0000,0000,,We had hoped for some kind\Nof spud-like thing
Dialogue: 0,0:08:09.12,0:08:11.28,Default,,0000,0000,0000,,where you could easily land.
Dialogue: 0,0:08:11.28,0:08:14.57,Default,,0000,0000,0000,,But we had one hope: maybe it was smooth.
Dialogue: 0,0:08:14.57,0:08:18.31,Default,,0000,0000,0000,,No. That didn't work either. (Laughter)
Dialogue: 0,0:08:18.31,0:08:21.00,Default,,0000,0000,0000,,So at that point in time,\Nit was clearly unavoidable:
Dialogue: 0,0:08:21.00,0:08:24.53,Default,,0000,0000,0000,,we had to map this body\Nin all the detail you could get,
Dialogue: 0,0:08:24.53,0:08:29.69,Default,,0000,0000,0000,,because we had to find an area\Nwhich is 500 meters in diameter and flat.
Dialogue: 0,0:08:29.69,0:08:34.29,Default,,0000,0000,0000,,Why 500 meters? That's the error\Nwe have on landing the probe.
Dialogue: 0,0:08:34.29,0:08:37.47,Default,,0000,0000,0000,,So we went through this process,\Nand we mapped the comet.
Dialogue: 0,0:08:37.47,0:08:39.83,Default,,0000,0000,0000,,We used a technique\Ncalled photoclinometry.
Dialogue: 0,0:08:39.83,0:08:42.06,Default,,0000,0000,0000,,You use shadows thrown by the sun.
Dialogue: 0,0:08:42.06,0:08:45.15,Default,,0000,0000,0000,,What you see here is a rock\Nsitting on the surface of the comet,
Dialogue: 0,0:08:45.15,0:08:48.08,Default,,0000,0000,0000,,and the sun shines from above.
Dialogue: 0,0:08:48.08,0:08:50.24,Default,,0000,0000,0000,,From the shadow, we, with our brain,
Dialogue: 0,0:08:50.24,0:08:53.88,Default,,0000,0000,0000,,can immediately determine\Nroughly what the shape of that rock is.
Dialogue: 0,0:08:53.88,0:08:55.92,Default,,0000,0000,0000,,You can program that in a computer,
Dialogue: 0,0:08:55.92,0:09:00.18,Default,,0000,0000,0000,,you then cover the whole comet,\Nand you can map the comet.
Dialogue: 0,0:09:00.18,0:09:03.86,Default,,0000,0000,0000,,For that, we flew special trajectories\Nstarting in August.
Dialogue: 0,0:09:03.86,0:09:06.76,Default,,0000,0000,0000,,First, a triangle\Nof 100 kilometers on a side
Dialogue: 0,0:09:06.76,0:09:08.43,Default,,0000,0000,0000,,at 100 kilometers' distance,
Dialogue: 0,0:09:08.43,0:09:11.43,Default,,0000,0000,0000,,and we repeated the whole \Nthing at 50 kilometers.
Dialogue: 0,0:09:11.43,0:09:15.08,Default,,0000,0000,0000,,At that time, we had seen the comet\Nat all kinds of angles,
Dialogue: 0,0:09:15.08,0:09:19.75,Default,,0000,0000,0000,,and we could use this technique\Nto map the whole thing.
Dialogue: 0,0:09:19.75,0:09:23.02,Default,,0000,0000,0000,,Now, this led to a selection\Nof landing sites.
Dialogue: 0,0:09:23.02,0:09:27.28,Default,,0000,0000,0000,,This whole process we had to do,\Nto go from the mapping of the comet
Dialogue: 0,0:09:27.28,0:09:30.84,Default,,0000,0000,0000,,to actually finding\Nthe final landing site, was 60 days.
Dialogue: 0,0:09:30.84,0:09:32.23,Default,,0000,0000,0000,,We didn't have more.
Dialogue: 0,0:09:32.23,0:09:34.35,Default,,0000,0000,0000,,To give you an idea,\Nthe average Mars mission
Dialogue: 0,0:09:34.35,0:09:38.13,Default,,0000,0000,0000,,takes hundreds of scientists\Nfor years to meet
Dialogue: 0,0:09:38.13,0:09:40.20,Default,,0000,0000,0000,,about where shall we go?
Dialogue: 0,0:09:40.20,0:09:42.36,Default,,0000,0000,0000,,We had 60 days, and that was it.
Dialogue: 0,0:09:42.36,0:09:45.40,Default,,0000,0000,0000,,We finally selected the final landing site
Dialogue: 0,0:09:45.40,0:09:50.46,Default,,0000,0000,0000,,and the commands were prepared\Nfor Rosetta to launch Philae.
Dialogue: 0,0:09:50.46,0:09:54.83,Default,,0000,0000,0000,,The way this works is that Rosetta\Nhas to be at the right point in space,
Dialogue: 0,0:09:54.83,0:09:57.65,Default,,0000,0000,0000,,and aiming towards the comet,\Nbecause the lander is passive.
Dialogue: 0,0:09:57.65,0:10:01.33,Default,,0000,0000,0000,,The lander is then pushed out\Nand moves towards the comet.
Dialogue: 0,0:10:01.33,0:10:03.12,Default,,0000,0000,0000,,Rosetta had to turn around
Dialogue: 0,0:10:03.12,0:10:07.68,Default,,0000,0000,0000,,to get its cameras to actually look\Nat Philae while it was departing
Dialogue: 0,0:10:07.68,0:10:10.15,Default,,0000,0000,0000,,and to be able to communicate with it.
Dialogue: 0,0:10:10.15,0:10:14.72,Default,,0000,0000,0000,,Now, the landing duration\Nof the whole trajectory was seven hours.
Dialogue: 0,0:10:14.72,0:10:17.51,Default,,0000,0000,0000,,Now do a simple calculation:
Dialogue: 0,0:10:17.51,0:10:21.55,Default,,0000,0000,0000,,if the velocity of Rosetta is off\Nby one centimeter per second,
Dialogue: 0,0:10:21.55,0:10:25.89,Default,,0000,0000,0000,,seven hours is 25,000 seconds.
Dialogue: 0,0:10:25.89,0:10:30.25,Default,,0000,0000,0000,,That means 252 meters wrong on the comet.
Dialogue: 0,0:10:30.25,0:10:33.60,Default,,0000,0000,0000,,So we had to know the velocity of Rosetta
Dialogue: 0,0:10:33.60,0:10:36.10,Default,,0000,0000,0000,,much better than\None centimeter per second,
Dialogue: 0,0:10:36.10,0:10:40.17,Default,,0000,0000,0000,,and its location in space\Nbetter than 100 meters
Dialogue: 0,0:10:40.17,0:10:43.37,Default,,0000,0000,0000,,at 500 million kilometers from Earth.
Dialogue: 0,0:10:43.37,0:10:45.74,Default,,0000,0000,0000,,That's no mean feat.
Dialogue: 0,0:10:45.74,0:10:50.13,Default,,0000,0000,0000,,Let me quickly take you through\Nsome of the science and the instruments.
Dialogue: 0,0:10:50.13,0:10:53.56,Default,,0000,0000,0000,,I won't bore you with all the details\Nof all the instruments,
Dialogue: 0,0:10:53.56,0:10:55.21,Default,,0000,0000,0000,,but it's got everything.
Dialogue: 0,0:10:55.21,0:10:58.35,Default,,0000,0000,0000,,We can sniff gas,\Nwe can measure dust particles,
Dialogue: 0,0:10:58.35,0:11:00.60,Default,,0000,0000,0000,,the shape of them, the composition,
Dialogue: 0,0:11:00.60,0:11:03.11,Default,,0000,0000,0000,,there are magnetometers, everything.
Dialogue: 0,0:11:03.11,0:11:06.71,Default,,0000,0000,0000,,This is one of the results from\Nan instrument which measures gas density
Dialogue: 0,0:11:06.71,0:11:08.56,Default,,0000,0000,0000,,at the position of Rosetta,
Dialogue: 0,0:11:08.56,0:11:10.79,Default,,0000,0000,0000,,so it's gas which has left the comet.
Dialogue: 0,0:11:10.79,0:11:13.28,Default,,0000,0000,0000,,The bottom graph\Nis September of last year.
Dialogue: 0,0:11:13.28,0:11:16.58,Default,,0000,0000,0000,,There is a long-term variation,\Nwhich in itself is not surprising,
Dialogue: 0,0:11:16.58,0:11:18.46,Default,,0000,0000,0000,,but you see the sharp peaks.
Dialogue: 0,0:11:18.46,0:11:20.55,Default,,0000,0000,0000,,This is a comet day.
Dialogue: 0,0:11:20.55,0:11:24.66,Default,,0000,0000,0000,,You can see the effect of the sun\Non the evaporation of gas
Dialogue: 0,0:11:24.66,0:11:27.60,Default,,0000,0000,0000,,and the fact that the comet is rotating.
Dialogue: 0,0:11:27.60,0:11:29.31,Default,,0000,0000,0000,,So there is one spot, apparently,
Dialogue: 0,0:11:29.31,0:11:31.46,Default,,0000,0000,0000,,where there is a lot of stuff coming from,
Dialogue: 0,0:11:31.46,0:11:34.76,Default,,0000,0000,0000,,it gets heated in the Sun,\Nand then cools down on the back side.
Dialogue: 0,0:11:34.76,0:11:38.26,Default,,0000,0000,0000,,And we can see\Nthe density variations of this.
Dialogue: 0,0:11:38.26,0:11:42.40,Default,,0000,0000,0000,,These are the gases\Nand the organic compounds
Dialogue: 0,0:11:42.40,0:11:44.09,Default,,0000,0000,0000,,that we already have measured.
Dialogue: 0,0:11:44.09,0:11:45.88,Default,,0000,0000,0000,,You will see it's an impressive list,
Dialogue: 0,0:11:45.88,0:11:48.36,Default,,0000,0000,0000,,and there is much, much,\Nmuch more to come,
Dialogue: 0,0:11:48.36,0:11:50.31,Default,,0000,0000,0000,,because there are more measurements.
Dialogue: 0,0:11:50.31,0:11:53.66,Default,,0000,0000,0000,,Actually, there is a conference\Ngoing on in Houston at the moment
Dialogue: 0,0:11:53.66,0:11:56.12,Default,,0000,0000,0000,,where many of these results are presented.
Dialogue: 0,0:11:56.83,0:11:58.45,Default,,0000,0000,0000,,Also, we measured dust particles.
Dialogue: 0,0:11:58.45,0:12:01.25,Default,,0000,0000,0000,,Now, for you, this will not\Nlook very impressive,
Dialogue: 0,0:12:01.25,0:12:04.52,Default,,0000,0000,0000,,but the scientists were thrilled\Nwhen they saw this.
Dialogue: 0,0:12:04.52,0:12:05.94,Default,,0000,0000,0000,,Two dust particles:
Dialogue: 0,0:12:05.94,0:12:08.93,Default,,0000,0000,0000,,the right one they call Boris,\Nand they shot it with tantalum
Dialogue: 0,0:12:08.93,0:12:11.05,Default,,0000,0000,0000,,in order to be able to analyze it.
Dialogue: 0,0:12:11.05,0:12:13.44,Default,,0000,0000,0000,,Now, we found sodium and magnesium.
Dialogue: 0,0:12:13.44,0:12:17.69,Default,,0000,0000,0000,,What this tells you is this is\Nthe concentration of these two materials
Dialogue: 0,0:12:17.69,0:12:20.40,Default,,0000,0000,0000,,at the time the solar system was formed,
Dialogue: 0,0:12:20.40,0:12:23.77,Default,,0000,0000,0000,,so we learned things about\Nwhich materials were there
Dialogue: 0,0:12:23.77,0:12:26.86,Default,,0000,0000,0000,,when the planet was made.
Dialogue: 0,0:12:26.86,0:12:29.58,Default,,0000,0000,0000,,Of course, one of the important\Nelements is the imaging.
Dialogue: 0,0:12:29.58,0:12:32.94,Default,,0000,0000,0000,,This is one of the cameras of Rosetta,\Nthe OSIRIS camera,
Dialogue: 0,0:12:32.94,0:12:35.94,Default,,0000,0000,0000,,and this actually was the cover\Nof Science magazine
Dialogue: 0,0:12:35.94,0:12:38.61,Default,,0000,0000,0000,,on January 23 of this year.
Dialogue: 0,0:12:38.61,0:12:42.05,Default,,0000,0000,0000,,Nobody had expected\Nthis body to look like this.
Dialogue: 0,0:12:42.05,0:12:45.64,Default,,0000,0000,0000,,Boulders, rocks -- if anything, it looks\Nmore like the Half Dome in Yosemite
Dialogue: 0,0:12:45.64,0:12:48.15,Default,,0000,0000,0000,,than anything else.
Dialogue: 0,0:12:48.15,0:12:50.73,Default,,0000,0000,0000,,We also saw things like this:
Dialogue: 0,0:12:50.73,0:12:55.65,Default,,0000,0000,0000,,dunes, and what look to be,\Non the righthand side, wind-blown shadows.
Dialogue: 0,0:12:55.65,0:12:59.58,Default,,0000,0000,0000,,Now we know these from Mars,\Nbut this comet doesn't have an atmosphere,
Dialogue: 0,0:12:59.58,0:13:02.45,Default,,0000,0000,0000,,so it's a bit difficult to create\Na wind-blown shadow.
Dialogue: 0,0:13:02.45,0:13:04.44,Default,,0000,0000,0000,,It may be local outgassing,
Dialogue: 0,0:13:04.44,0:13:06.62,Default,,0000,0000,0000,,stuff which goes up and comes back.
Dialogue: 0,0:13:06.62,0:13:09.80,Default,,0000,0000,0000,,We don't know, so there is\Na lot to investigate.
Dialogue: 0,0:13:09.80,0:13:11.89,Default,,0000,0000,0000,,Here, you see the same image twice.
Dialogue: 0,0:13:11.89,0:13:14.41,Default,,0000,0000,0000,,On the left-hand side,\Nyou see in the middle a pit.
Dialogue: 0,0:13:14.41,0:13:16.63,Default,,0000,0000,0000,,On the right-hand side,\Nif you carefully look,
Dialogue: 0,0:13:16.63,0:13:19.86,Default,,0000,0000,0000,,there are three jets coming out\Nof the bottom of that pit.
Dialogue: 0,0:13:19.86,0:13:22.16,Default,,0000,0000,0000,,So this is the activity of the comet.
Dialogue: 0,0:13:22.16,0:13:26.17,Default,,0000,0000,0000,,Apparently, at the bottom of these pits\Nis where the active regions are,
Dialogue: 0,0:13:26.17,0:13:28.94,Default,,0000,0000,0000,,and where the material\Nevaporates into space.
Dialogue: 0,0:13:28.94,0:13:32.54,Default,,0000,0000,0000,,There is a very intriguing crack\Nin the neck of the comet.
Dialogue: 0,0:13:32.54,0:13:34.54,Default,,0000,0000,0000,,You see it on the right-hand side.
Dialogue: 0,0:13:34.54,0:13:38.24,Default,,0000,0000,0000,,It's a kilometer long,\Nand it's two and a half meters wide.
Dialogue: 0,0:13:38.24,0:13:40.48,Default,,0000,0000,0000,,Some people suggest that actually,
Dialogue: 0,0:13:40.48,0:13:42.55,Default,,0000,0000,0000,,when we get close to the sun,
Dialogue: 0,0:13:42.55,0:13:44.41,Default,,0000,0000,0000,,the comet may split in two,
Dialogue: 0,0:13:44.41,0:13:46.09,Default,,0000,0000,0000,,and then we'll have to choose,
Dialogue: 0,0:13:46.09,0:13:48.34,Default,,0000,0000,0000,,which comet do we go for?
Dialogue: 0,0:13:48.34,0:13:51.51,Default,,0000,0000,0000,,The lander -- again, lots of instruments,
Dialogue: 0,0:13:51.51,0:13:56.86,Default,,0000,0000,0000,,mostly comparable except for the things\Nwhich hammer in the ground and drill, etc.
Dialogue: 0,0:13:56.86,0:14:00.73,Default,,0000,0000,0000,,But much the same as Rosetta, and that is\Nbecause you want to compare
Dialogue: 0,0:14:00.73,0:14:04.24,Default,,0000,0000,0000,,what you find in space\Nwith what you find on the comet.
Dialogue: 0,0:14:04.24,0:14:06.93,Default,,0000,0000,0000,,These are called\Nground truth measurements.
Dialogue: 0,0:14:06.93,0:14:10.16,Default,,0000,0000,0000,,These are the landing descent images
Dialogue: 0,0:14:10.16,0:14:12.21,Default,,0000,0000,0000,,that were taken by the OSIRIS camera.
Dialogue: 0,0:14:12.21,0:14:16.44,Default,,0000,0000,0000,,You see the lander getting further\Nand further away from Rosetta.
Dialogue: 0,0:14:16.44,0:14:20.24,Default,,0000,0000,0000,,On the top right, you see an image\Ntaken at 60 meters by the lander,
Dialogue: 0,0:14:20.24,0:14:23.10,Default,,0000,0000,0000,,60 meters above the surface of the comet.
Dialogue: 0,0:14:23.10,0:14:25.51,Default,,0000,0000,0000,,The boulder there is some 10 meters.
Dialogue: 0,0:14:25.51,0:14:30.23,Default,,0000,0000,0000,,So this is one of the last images we took\Nbefore we landed on the comet.
Dialogue: 0,0:14:30.23,0:14:33.79,Default,,0000,0000,0000,,Here, you see the whole sequence again,\Nbut from a different perspective,
Dialogue: 0,0:14:33.79,0:14:37.97,Default,,0000,0000,0000,,and you see three blown-ups\Nfrom the bottom-left to the middle
Dialogue: 0,0:14:37.97,0:14:42.16,Default,,0000,0000,0000,,of the lander traveling\Nover the surface of the comet.
Dialogue: 0,0:14:42.16,0:14:46.34,Default,,0000,0000,0000,,Then, at the top, there is a before\Nand an after image of the landing.
Dialogue: 0,0:14:46.34,0:14:50.27,Default,,0000,0000,0000,,The only problem with the after image is,\Nthere is no lander.
Dialogue: 0,0:14:50.27,0:14:53.54,Default,,0000,0000,0000,,But if you carefully look\Nat the right-hand side of this image,
Dialogue: 0,0:14:53.54,0:14:57.57,Default,,0000,0000,0000,,we saw the lander still there, \Nbut it had bounced.
Dialogue: 0,0:14:57.57,0:14:59.23,Default,,0000,0000,0000,,It had departed again.
Dialogue: 0,0:14:59.23,0:15:02.32,Default,,0000,0000,0000,,Now, on a bit of a comical note here
Dialogue: 0,0:15:02.32,0:15:06.94,Default,,0000,0000,0000,,is that originally Rosetta was designed\Nto have a lander which would bounce.
Dialogue: 0,0:15:06.94,0:15:09.51,Default,,0000,0000,0000,,That was discarded because\Nit was way too expensive.
Dialogue: 0,0:15:09.51,0:15:11.78,Default,,0000,0000,0000,,Now, we forgot, but the lander knew.
Dialogue: 0,0:15:11.78,0:15:13.39,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:15:13.39,0:15:15.90,Default,,0000,0000,0000,,During the first bounce,\Nin the magnetometers,
Dialogue: 0,0:15:15.90,0:15:19.72,Default,,0000,0000,0000,,you see here the data from them,\Nfrom the three axes, x, y and z.
Dialogue: 0,0:15:19.72,0:15:21.93,Default,,0000,0000,0000,,Halfway through, you see a red line.
Dialogue: 0,0:15:21.93,0:15:23.76,Default,,0000,0000,0000,,At that red line, there is a change.
Dialogue: 0,0:15:23.76,0:15:27.69,Default,,0000,0000,0000,,What happened, apparently,\Nis during the first bounce,
Dialogue: 0,0:15:27.69,0:15:32.42,Default,,0000,0000,0000,,somewhere, we hit the edge of a crater\Nwith one of the legs of the lander,
Dialogue: 0,0:15:32.42,0:15:35.24,Default,,0000,0000,0000,,and the rotation velocity\Nof the lander changed.
Dialogue: 0,0:15:35.24,0:15:37.21,Default,,0000,0000,0000,,So we've been rather lucky
Dialogue: 0,0:15:37.21,0:15:39.48,Default,,0000,0000,0000,,that we are where we are.
Dialogue: 0,0:15:39.48,0:15:43.15,Default,,0000,0000,0000,,This is one of\Nthe iconic images of Rosetta.
Dialogue: 0,0:15:43.15,0:15:47.08,Default,,0000,0000,0000,,It's a man-made object,\Na leg of the lander,
Dialogue: 0,0:15:47.08,0:15:49.03,Default,,0000,0000,0000,,standing on a comet.
Dialogue: 0,0:15:49.03,0:15:54.16,Default,,0000,0000,0000,,This, for me, is one of the very best\Nimages of space science I have ever seen.
Dialogue: 0,0:15:54.16,0:15:59.34,Default,,0000,0000,0000,,(Applause)
Dialogue: 0,0:15:59.34,0:16:03.19,Default,,0000,0000,0000,,One of the things we still have to do\Nis to actually find the lander.
Dialogue: 0,0:16:03.19,0:16:06.89,Default,,0000,0000,0000,,The blue area here\Nis where we know it must be.
Dialogue: 0,0:16:06.89,0:16:10.50,Default,,0000,0000,0000,,We haven't been able to find it yet,\Nbut the search is continuing,
Dialogue: 0,0:16:10.50,0:16:14.27,Default,,0000,0000,0000,,as are our efforts to start getting\Nthe lander to work again.
Dialogue: 0,0:16:14.27,0:16:16.01,Default,,0000,0000,0000,,We listen every day,
Dialogue: 0,0:16:16.01,0:16:18.57,Default,,0000,0000,0000,,and we hope that between now\Nand somewhere in April,
Dialogue: 0,0:16:18.57,0:16:20.31,Default,,0000,0000,0000,,the lander will wake up again.
Dialogue: 0,0:16:20.31,0:16:22.44,Default,,0000,0000,0000,,The findings of what\Nwe found on the comet:
Dialogue: 0,0:16:23.80,0:16:26.25,Default,,0000,0000,0000,,This thing would float in water.
Dialogue: 0,0:16:26.25,0:16:28.88,Default,,0000,0000,0000,,It's half the density of water.
Dialogue: 0,0:16:28.88,0:16:31.89,Default,,0000,0000,0000,,So it looks like\Na very big rock, but it's not.
Dialogue: 0,0:16:31.89,0:16:35.54,Default,,0000,0000,0000,,The activity increase we saw\Nin June, July, August last year
Dialogue: 0,0:16:35.54,0:16:37.93,Default,,0000,0000,0000,,was a four-fold activity increase.
Dialogue: 0,0:16:37.93,0:16:39.67,Default,,0000,0000,0000,,By the time we will be at the sun,
Dialogue: 0,0:16:39.67,0:16:44.25,Default,,0000,0000,0000,,there will be 100 kilos\Na second leaving this comet:
Dialogue: 0,0:16:44.25,0:16:45.80,Default,,0000,0000,0000,,gas, dust, whatever.
Dialogue: 0,0:16:45.80,0:16:48.33,Default,,0000,0000,0000,,That's 100 million kilos a day.
Dialogue: 0,0:16:49.60,0:16:51.98,Default,,0000,0000,0000,,Then, finally, the landing day.
Dialogue: 0,0:16:51.98,0:16:57.37,Default,,0000,0000,0000,,I will never forget -- absolute madness,\N250 TV crews in Germany.
Dialogue: 0,0:16:57.37,0:16:59.38,Default,,0000,0000,0000,,The BBC was interviewing me,
Dialogue: 0,0:16:59.38,0:17:02.36,Default,,0000,0000,0000,,and another TV crew\Nwho was following me all day
Dialogue: 0,0:17:02.36,0:17:04.49,Default,,0000,0000,0000,,were filming me being interviewed,
Dialogue: 0,0:17:04.49,0:17:06.93,Default,,0000,0000,0000,,and it went on like that\Nfor the whole day.
Dialogue: 0,0:17:06.93,0:17:08.74,Default,,0000,0000,0000,,The Discovery Channel crew
Dialogue: 0,0:17:08.74,0:17:11.06,Default,,0000,0000,0000,,actually caught me\Nwhen leaving the control room,
Dialogue: 0,0:17:11.06,0:17:13.18,Default,,0000,0000,0000,,and they asked the right question,
Dialogue: 0,0:17:13.18,0:17:16.80,Default,,0000,0000,0000,,and man, I got into tears,\Nand I still feel this.
Dialogue: 0,0:17:16.80,0:17:18.48,Default,,0000,0000,0000,,For a month and a half,
Dialogue: 0,0:17:18.48,0:17:21.32,Default,,0000,0000,0000,,I couldn't think about\Nlanding day without crying,
Dialogue: 0,0:17:21.32,0:17:24.03,Default,,0000,0000,0000,,and I still have the emotion in me.
Dialogue: 0,0:17:24.03,0:17:26.98,Default,,0000,0000,0000,,With this image of the comet,\NI would like to leave you.
Dialogue: 0,0:17:26.98,0:17:29.10,Default,,0000,0000,0000,,Thank you.
Dialogue: 0,0:17:29.10,0:17:33.98,Default,,0000,0000,0000,,(Applause)