Fred Jansen: How to land on a comet

Prevoditelj: Martina Juranic Recezent: Katarina Smetko

I'd like to take you on the epic quest of the Rosetta spacecraft.

Želio bih vas povesti na epsko putovanje svemirske letjelice Rosetta.

To escort and land the probe on a comet,

Praćenje i prizemljavanje sonde na komet

this has been my passion for the past two years.

bila je moja strast zadnjih dvije godine.

In order to do that,

Da bih to učinio,

I need to explain to you something about the origin of the solar system.

moram vam objasniti nekoliko stvari o postanku Sunčevog sustava.

Prije četiri i pol milijarde godina,

When we go back four and a half billion years,

there was a cloud of gas and dust.

postojao je samo oblak plina i prašine.

In the center of this cloud, our sun formed and ignited.

U središtu tog oblaka nastalo je naše Sunce i upalilo se.

Along with that, what we now know as planets, comets and asteroids formed.

Istovremeno je nastalo ono što danas zovemo planetima, kometima i asteroidima.

What then happened, according to theory,

Zatim, kaže teorija,

is that when the Earth had cooled down a bit after its formation,

kad se Zemlja oblikovala i ohladila,

comets massively impacted the Earth and delivered water to Earth.

bila je izložena udarima brojnih kometa koji su donijeli vodu.

They probably also delivered complex organic material to Earth,

Oni su vjerojatno na Zemlju donijeli i složene organske spojeve

and that may have bootstrapped the emergence of life.

i tako pokrenuli razvoj života.

You can compare this to having to solve a 250-piece puzzle

Možete to usporediti sa slaganjem slagalice od 250 komada,

and not a 2,000-piece puzzle.

umjesto od njih dvije tisuće.

Afterwards, the big planets like Jupiter and Saturn,

Kasnije su veliki planeti poput Jupitera i Saturna,

they were not in their place where they are now,

koji nisu bili ondje gdje su danas,

and they interacted gravitationally,

gravitacijom djelovali jedni na druge

and they swept the whole interior of the solar system clean,

i očistili cijeli Sunčev sustav,

and what we now know as comets

a ono što danas nazivamo kometima

ended up in something called the Kuiper Belt,

završilo je u takozvanom Kuiperovom pojasu,

which is a belt of objects beyond the orbit of Neptune.

što je pojas objekata iza Neptunove orbite.

And sometimes these objects run into each other,

Ponekad ti objekti nalete jedan na drugoga,

and they gravitationally deflect,

gravitacijski se odbiju,

and then the gravity of Jupiter pulls them back into the solar system.

a zatim ih Jupiterova gravitacija ponovno privuče u Sunčev sustav.

And they then become the comets as we see them in the sky.

Oni tada postanu kometi koje vidimo na nebu.

The important thing here to note is that in the meantime,

Ovdje je važno napomenuti da su se u međuvremenu,

the four and a half billion years,

tijekom četiri i pol milijarde godina,

these comets have been sitting on the outside of the solar system,

ti kometi nalazili izvan Sunčevog sustava

and haven't changed --

i nisu se promijenili --

deep, frozen versions of our solar system.

oni su duboko zamrznute verzije našeg Sunčevog sustava.

In the sky, they look like this.

Na nebu izgledaju ovako.

We know them for their tails.

Prepoznajemo ih po repovima.

There are actually two tails.

Zapravo imaju dva repa.

One is a dust tail, which is blown away by the solar wind.

Jedan je rep od prašine, koji Sunčev vjetar otpuše.

The other one is an ion tail, which is charged particles,

Drugi je ionski rep, od nabijenih čestica

and they follow the magnetic field in the solar system.

koje prate magnetsko polje Sunčevog sustava.

There's the coma,

Tu je koma,

and then there is the nucleus, which here is too small to see,

zatim jezgra, koja se ovdje ne vidi jer je premalena.

and you have to remember that in the case of Rosetta,

Imajte na umu da se, kad je u pitanju Rosetta,

the spacecraft is in that center pixel.

ta svemirska letjelica nalazi u tom središnjem pikselu.

We are only 20, 30, 40 kilometers away from the comet.

Udaljeni smo od kometa tek 20, 30, 40 kilometara.

So what's important to remember?

Dakle, što je potrebno zapamtiti?

Comets contain the original material from which our solar system was formed,

Kometi sadrže izvorni materijal od kojeg je načinjen naš Sunčev sustav

so they're ideal to study the components

tako da su idealni za proučavanje elemenata

that were present at the time when Earth, and life, started.

koji su bili prisutni u vrijeme nastanka Zemlje i života na njoj.

Comets are also suspected

Pretpostavlja se također da su kometi

of having brought the elements which may have bootstrapped life.

na Zemlju donijeli elemente koji su pokrenuli razvoj života.

In 1983, ESA set up its long-term Horizon 2000 program,

Godine 1983., ESA je pokrenula dugoročni program Horizon 2000,

which contained one cornerstone, which would be a mission to a comet.

a jedna od njegovih ključnih točaka bila je misija slijetanja na komet.

In parallel, a small mission to a comet, what you see here, Giotto, was launched,

Usporedno je pokrenuta manja misija Giotto, koju vidite ovdje,

and in 1986, flew by the comet of Halley with an armada of other spacecraft.

a ona je 1986. proletjela pokraj Halleyevog kometa, s drugim letjelicama.

From the results of that mission, it became immediately clear

Rezultati te misije jasno su pokazali

that comets were ideal bodies to study to understand our solar system.

da su kometi idealna tijela za proučavanje i razumijevanje našeg Sunčevog sustava.

And thus, the Rosetta mission was approved in 1993,

I tako je misija Rosetta odobrena 1993. godine,

and originally it was supposed to be launched in 2003,

i izvorno je trebala biti lansirana 2003.,

but a problem arose with an Ariane rocket.

ali došlo je do problema s raketom Ariane.

However, our P.R. department, in its enthusiasm,

Međutim, naša služba za odnose s javnošću entuzijastično je

had already made 1,000 Delft Blue plates

već bila dala izraditi 1000 porculanskih tanjura

with the name of the wrong comets.

s imenom pogrešnog kometa.

So I've never had to buy any china since. That's the positive part.

Tako da otad više ne moram kupovati porculansko posuđe. To je dobra strana.

(Laughter)

(Smijeh)

Once the whole problem was solved,

Kad je problem riješen,

we left Earth in 2004

2004. godine otisnuli smo se sa Zemlje

to the newly selected comet, Churyumov-Gerasimenko.

na novoodabran komet Čurjumov-Gerasimenko.

This comet had to be specially selected

Taj je komet odabran prvenstveno zato

because A, you have to be able to get to it,

jer je, pod A, morao biti pristupačan

and B, it shouldn't have been in the solar system too long.

i B, nije smio predugo biti u Sunčevom sustavu.

This particular comet has been in the solar system since 1959.

Taj je komet u Sunčevom sustavu od 1959. godine.

That's the first time when it was deflected by Jupiter,

Tada mu je Jupiter po prvi put skrenuo putanju

and it got close enough to the sun to start changing.

i približio se dovoljno blizu Suncu da se počne mijenjati.

So it's a very fresh comet.

Tako da je to vrlo nov komet.

Rosetta made a few historic firsts.

Rosetta je u mnogočemu bila prva u povijesti.

It's the first satellite to orbit a comet,

Prvi je satelit koji je kružio u orbiti oko kometa,

and to escort it throughout its whole tour through the solar system --

te ga pratio tijekom cijele putanje oko Sunčevog sustava --

closest approach to the sun, as we will see in August,

najviše će se približiti Suncu u kolovozu, kao što ćemo vidjeti,

and then away again to the exterior.

i onda se ponovno udaljiti.

It's the first ever landing on a comet.

Prvi je satelit koji je ikada sletio na komet.

We actually orbit the comet using something which is not

Kružili smo oko kometa pomoću nečega što nije

normally done with spacecraft.

uobičajeno za svemirsku letjelicu.

Obično pogledate nebo i znate kamo pokazujete i gdje se nalazite.

Normally, you look at the sky and you know where you point and where you are.

In this case, that's not enough.

U ovom slučaju, to nije bilo dovoljno.

We navigated by looking at landmarks on the comet.

Pri navigaciji smo se koristili obilježjima samoga kometa.

We recognized features -- boulders, craters --

Prateći obilježja poput stijena i kratera,

and that's how we know where we are respective to the comet.

znali smo gdje se nalazimo u odnosu na komet.

And, of course, it's the first satellite to go beyond the orbit of Jupiter

I naravno, to je prvi satelit koji je stigao dalje od Jupiterove orbite

on solar cells.

pomoću solarnih ćelija.

Now, this sounds more heroic than it actually is,

To zvuči više herojski nego što to zaista jest,

because the technology to use radio isotope thermal generators

zato što tehnologija korištenja radioizotopskih termalnih generatora

wasn't available in Europe at that time, so there was no choice.

tada nije bila dostupna u Europi, tako da nismo imali drugog izbora.

But these solar arrays are big.

Ali ovi su solarni paneli veliki.

This is one wing, and these are not specially selected small people.

Ovo je jedno krilo i to nisu posebno odabrani niski ljudi.

They're just like you and me.

Oni su poput vas i mene.

(Laughter)

(Smijeh)

We have two of these wings, 65 square meters.

Imamo dva takva krila od 65 četvornih metara.

Now later on, of course, when we got to the comet,

Naravno, kasnije, kad stignete do kometa,

you find out that 65 square meters of sail

otkrijete da 65 četvornih metara jedara

close to a body which is outgassing is not always a very handy choice.

blizu tijela koje ispušta plin i nije najpraktičniji izbor.

Now, how did we get to the comet?

Kako smo došli do kometa?

Because we had to go there for the Rosetta scientific objectives

Zbog Rosettine znanstvene svrhe, morali smo otići

very far away -- four times the distance of the Earth to the sun --

jako daleko, na udaljenost četiri puta veću od one između Zemlje i Sunca,

and also at a much higher velocity than we could achieve with fuel,

i pri puno većoj brzini nego što bismo je mogli postići uz gorivo

because we'd have to take six times as much fuel as the whole spacecraft weighed.

jer bi nam trebalo šest puta više goriva nego što teži cijela letjelica.

So what do you do?

Dakle, što učiniti?

You use gravitational flybys, slingshots,

Valja iskoristiti gravitacijske praćke

where you pass by a planet at very low altitude,

gdje prilikom prolaska kraj planeta na vrlo malenoj visini

a few thousand kilometers,

od nekoliko tisuća kilometara,

and then you get the velocity of that planet around the sun for free.

možete besplatno iskoristiti brzinu kretanja tog planeta oko Sunca.

We did that a few times.

Učinili smo to nekoliko puta.

We did Earth, we did Mars, we did twice Earth again,

Iskoristili smo Zemlju, Mars i Zemlju još dva puta,

and we also flew by two asteroids, Lutetia and Steins.

i letjeli smo uz dva asteroida, Lutetiju i Steins.

Then in 2011, we got so far from the sun that if the spacecraft got into trouble,

Zatim smo se 2011. toliko udaljili od Sunca da se letjelica našla u problemima.

we couldn't actually save the spacecraft anymore,

Nismo je više mogli spasiti

so we went into hibernation.

pa smo je stavili u mirovanje.

Everything was switched off except for one clock.

Sve smo ugasili osim jednog sata.

Here you see in white the trajectory, and the way this works.

Ovdje je bijelom bojom prikazana putanja i način na koji funkcionira.

You see that from the circle where we started,

Vidite da se taj krug koji smo imali na početku -

the white line, actually you get more and more and more elliptical,

označen bijelom bojom - postupno pretvorio u elipsu

and then finally we approached the comet

i konačno smo stigli do kometa

in May 2014, and we had to start doing the rendezvous maneuvers.

u svibnju 2014., te smo trebali započeti sa spajanjem.

On the way there, we flew by Earth and we took a few pictures to test our cameras.

Na putu tamo, prošli smo uz Zemlju i snimili pokoju sliku da isprobamo kamere.

This is the moon rising over Earth,

Ovo je izlazak Mjeseca nad Zemljom,

and this is what we now call a selfie,

a ovo je ono što danas zovemo "selfie",

which at that time, by the way, that word didn't exist. (Laughter)

riječ koja u to vrijeme, usput, nije postajala. (Smijeh)

It's at Mars. It was taken by the CIVA camera.

Mars snimljen pomoću CIVA kamere.

That's one of the cameras on the lander,

To je jedna od kamera na sondi,

and it just looks under the solar arrays,

snima ispod solarnih panela

and you see the planet Mars and the solar array in the distance.

i vidite planet Mars i solarne panele u daljini.

Now, when we got out of hibernation in January 2014,

Kad smo u siječnju 2014. izašli iz mirovanja,

započeli smo približavanje kometu

we started arriving at a distance

of two million kilometers from the comet in May.

i u svibnju stigli na udaljenost od dva milijuna kilometara od kometa.

However, the velocity the spacecraft had was much too fast.

Međutim, brzina letjelice je bila prevelika.

We were going 2,800 kilometers an hour faster than the comet, so we had to brake.

Išli smo 2 800 km na sat brže nego komet, tako da smo morali kočiti.

We had to do eight maneuvers,

Morali smo napraviti osam manevra

and you see here, some of them were really big.

i kao što vidite ovdje, neki od njih su poprilično dugački.

We had to brake the first one by a few hundred kilometers per hour,

Prvo smo trebali kočiti nekoliko stotina kilometara na sat,

and actually, the duration of that was seven hours,

što je trajalo sedam sati

and it used 218 kilos of fuel,

i za što je iskorišteno 218 kg goriva.

and those were seven nerve-wracking hours, because in 2007,

Bilo je to sedam vrlo napetih sati jer je 2007. godine

there was a leak in the system of the propulsion of Rosetta,

došlo do propuštanja u Rosettinom pogonskom sustavu.

and we had to close off a branch,

i morali smo zatvoriti odjeljak,

so the system was actually operating at a pressure

tako da je sustav radio pri tlaku

which it was never designed or qualified for.

za koji nije bio dizajniran niti namijenjen.

Then we got in the vicinity of the comet, and these were the first pictures we saw.

Zatim smo se približili kometu i ovo su bile prve slike koje smo vidjeli.

The true comet rotation period is 12 and a half hours,

Rotacija kometa u stvarnosti traje dvanaest i pol sati,

so this is accelerated,

tako da je ovo ubrzana snimka,

but you will understand that our flight dynamics engineers thought,

ali razumjet ćete zašto su naši inženjeri dinamike leta smatrali

this is not going to be an easy thing to land on.

da ovamo neće biti lako sletjeti.

We had hoped for some kind of spud-like thing

Nadali smo nekoj vrsti krumpirastog oblika

where you could easily land.

koji bi olakšavao slijetanje.

But we had one hope: maybe it was smooth.

Ostala nam je samo nada da će možda biti gladak.

No. That didn't work either. (Laughter)

Ne. Nije bio niti to. (Smijeh)

So at that point in time, it was clearly unavoidable:

Tako da je u tom trenutku postalo jasno da ćemo neizbježno

we had to map this body in all the detail you could get,

morati mapirati to tijelo do u najsitnije pojedinosti,

because we had to find an area which is 500 meters in diameter and flat.

jer smo morali pronaći ravno područje promjera 500 metara.

Why 500 meters? That's the error we have on landing the probe.

Zašto 500 metara? To je greška koja se događa prilikom slijetanja sonde.

So we went through this process, and we mapped the comet.

I prošli smo kroz taj proces i mapirali komet.

We used a technique called photoclinometry.

Koristili smo tehniku koja se zove fotoklinometrija.

You use shadows thrown by the sun.

Koristite sjene koje stvara Sunce.

What you see here is a rock sitting on the surface of the comet,

Ovdje vidite stijenu koja se nalazi na površini kometa,

and the sun shines from above.

a iznad nje sja Sunce.

From the shadow, we, with our brain,

Pomoću te sjene, koristeći svoj mozak,

can immediately determine roughly what the shape of that rock is.

možemo odmah ugrubo odrediti kakvog je oblika stijena.

You can program that in a computer,

To se može programirati u računalo,

you then cover the whole comet, and you can map the comet.

prekriti cijeli komet i mapirati ga.

For that, we flew special trajectories starting in August.

U tu smo se svrhu u kolovozu počeli kretati posebnim putanjama.

First, a triangle of 100 kilometers on a side

Prvo, trokut sa stranama od 100 kilometara

at 100 kilometers' distance,

na udaljenosti od 100 kilometara

and we repeated the whole thing at 50 kilometers.

i to smo onda ponovili na 50 kilometara.

At that time, we had seen the comet at all kinds of angles,

U tom smo trenutku već promotrili komet iz svih kuteva

and we could use this technique to map the whole thing.

i mogli smo koristiti tu tehniku kako bismo ga mapirali.

Now, this led to a selection of landing sites.

To je dovelo do odabira mjesta za slijetanje.

This whole process we had to do, to go from the mapping of the comet

Cijeli proces koji smo morali proći od mapiranja kometa

to actually finding the final landing site, was 60 days.

do pronalaska konačnog mjesta za slijetanje trajao je 60 dana.

We didn't have more.

Nismo imali više.

To give you an idea, the average Mars mission

Da vam to predočim, prilikom prosječne misije na Mars

takes hundreds of scientists for years to meet

stotine znanstvenika godinama se sastaju

about where shall we go?

prije nego odluče kamo će se ići.

We had 60 days, and that was it.

Mi smo imali 60 dana i to je bilo to.

We finally selected the final landing site

Naposljetku smo izabrali mjesto za slijetanje

and the commands were prepared for Rosetta to launch Philae.

i bile su pripremljene naredbe za Rosettino lansiranje Philae.

The way this works is that Rosetta has to be at the right point in space,

To funkcionira tako da Rosetta mora biti na točno određenom mjestu

and aiming towards the comet, because the lander is passive.

i usmjerena prema kometu jer je sonda neaktivna.

The lander is then pushed out and moves towards the comet.

Sonda se tada otpušta i usmjerava prema kometu.

Rosetta had to turn around

Rosetta se trebala okrenuti

to get its cameras to actually look at Philae while it was departing

kako bi kamere bile usmjerene prema Philae dok se udaljavala

and to be able to communicate with it.

i kako bi mogle komunicirati.

Now, the landing duration of the whole trajectory was seven hours.

Slijetanje je trajalo sedam sati.

Now do a simple calculation:

Napravimo jednostavan izračun:

if the velocity of Rosetta is off by one centimeter per second,

da je u izračunu Rosettine brzine došlo do pogreške od 1 centimetra u sekundi,

seven hours is 25,000 seconds.

a sedam sati je 25 000 sekundi,

That means 252 meters wrong on the comet.

to bi značilo pogrešku od 252 metra u odnosu na komet.

So we had to know the velocity of Rosetta

Tako da smo trebali znati brzinu Rosette

much better than one centimeter per second,

mnogo bolje nego jedan centimetar po sekundi

and its location in space better than 100 meters

i njen položaj u svemiru preciznije nego 100 metara

at 500 million kilometers from Earth.

na 500 milijuna kilometra od Zemlje.

That's no mean feat.

To nije mala stvar.

Let me quickly take you through some of the science and the instruments.

Dopustite mi da vas brzo provedem kroz znanstvenu podlogu i instrumente.

I won't bore you with all the details of all the instruments,

Neću vam dosađivati detaljima o svim instrumentima,

but it's got everything.

ali ima sve.

We can sniff gas, we can measure dust particles,

Možemo onjušiti plin, izmjeriti čestice prašine,

the shape of them, the composition,

njihov oblik, sastav,

there are magnetometers, everything.

opskrbljena je magnetometrima, svime.

This is one of the results from an instrument which measures gas density

Ovo je jedan od rezultata dobiven instrumentom koji mjeru gustoću plina

at the position of Rosetta,

na Rosettinom položaju,

so it's gas which has left the comet.

tako da je to plin koji potječe s kometa.

The bottom graph is September of last year.

Donji je graf iz rujna prošle godine.

There is a long-term variation, which in itself is not surprising,

Postoji dugoročno odstupanje što i nije iznenađujuće,

but you see the sharp peaks.

ali vide se oštri šiljci.

This is a comet day.

To je dan kometa.

You can see the effect of the sun on the evaporation of gas

Možete vidjeti utjecaj Sunca na isparavanje plinova

and the fact that the comet is rotating.

i činjenicu da se komet rotira.

So there is one spot, apparently,

Dakle, čini se da postoji jedno mjesto

where there is a lot of stuff coming from,

odakle izlazi puno toga.

it gets heated in the Sun, and then cools down on the back side.

Sunce ga zagrijava, a onda se hladi na stražnjoj strani.

And we can see the density variations of this.

Možemo vidjeti i varijacije gustoće.

These are the gases and the organic compounds

Ovo su plinovi i organski spojevi

that we already have measured.

koje smo već izmjerili.

You will see it's an impressive list,

Možete vidjeti da je to zadivljujuća lista

and there is much, much, much more to come,

i još će puno, puno toga uslijediti

because there are more measurements.

jer će biti još mjerenja.

Actually, there is a conference going on in Houston at the moment

Zapravo, u Houstonu se upravo održava konferencija

where many of these results are presented.

na kojoj će biti predstavljen velik dio ovih rezultata.

Also, we measured dust particles.

Izmjerili smo i čestice prašine.

Now, for you, this will not look very impressive,

Vama to neće puno značiti,

but the scientists were thrilled when they saw this.

ali znanstvenike je ovo oduševilo.

Two dust particles:

Dvije čestice prašine:

the right one they call Boris, and they shot it with tantalum

desnu su nazvali Boris i gađali je česticama tantala

in order to be able to analyze it.

kako bi ju mogli analizirati.

Now, we found sodium and magnesium.

Pronašli su natrij i magnezij.

What this tells you is this is the concentration of these two materials

To nam govori da se radi o koncentraciji tih dvaju materijala

at the time the solar system was formed,

u trenutku nastanka Sunčevog sustava.

so we learned things about which materials were there

Tako smo naučili koji su elementi bili prisutni

when the planet was made.

u vrijeme nastanka planeta.

Of course, one of the important elements is the imaging.

Naravno, jedna od važnijih stvari jest dobivanje slika.

This is one of the cameras of Rosetta, the OSIRIS camera,

Ovo je snimila jedna od kamera na Rosetti, kamera OSIRIS,

and this actually was the cover of Science magazine

i ta je slika završila na naslovnici časopisa Science

on January 23 of this year.

objavljenog 23. siječnja ove godine.

Nobody had expected this body to look like this.

Nitko nije očekivao da će ovo tijelo ovako izgledati --

Boulders, rocks -- if anything, it looks more like the Half Dome in Yosemite

stijene, kamenje --izgleda kao Half Dome u Yosemiteu

than anything else.

više nego bilo što drugo.

We also saw things like this:

VIdjeli smo i stvari poput ove:

dunes, and what look to be, on the righthand side, wind-blown shadows.

dine i na desnoj strani, čini se, brazde nastale djelovanjem vjetra.

Now we know these from Mars, but this comet doesn't have an atmosphere,

Znamo za njih s Marsa, ali ovaj komet nema svoju atmosferu,

so it's a bit difficult to create a wind-blown shadow.

tako da je teško stvoriti takvu brazdu.

It may be local outgassing,

Možda je to mjestimično ispuhivanje plinova,

stuff which goes up and comes back.

stvari koje odu gore i onda se vrate.

We don't know, so there is a lot to investigate.

Ne znamo, ostalo je još puno toga za istražti

Here, you see the same image twice.

Ovdje vidite istu sliku dvaput.

On the left-hand side, you see in the middle a pit.

Na lijevoj strani u sredini vidite jamu.

On the right-hand side, if you carefully look,

Na desnoj slici, ako pažljivo pogledate,

there are three jets coming out of the bottom of that pit.

s dna te jame izbijaju tri mlaza.

So this is the activity of the comet.

Dakle, tako izgleda aktivnost kometa.

Apparently, at the bottom of these pits is where the active regions are,

Čini se da se na dnu tih jama nalaze aktivna područja

and where the material evaporates into space.

iz kojih materijal isparava u svemir.

There is a very intriguing crack in the neck of the comet.

Na "vratu" kometa nalazi se vrlo zanimljiva pukotina.

You see it on the right-hand side.

Vidite je na desnoj strani.

It's a kilometer long, and it's two and a half meters wide.

Duga je kilometar i široka dva i pol metra.

Some people suggest that actually,

Neki ljudi smatraju da će se,

when we get close to the sun,

kad dođe blizu Sunca,

the comet may split in two,

komet možda raspoloviti

and then we'll have to choose,

i u tom ćemo slučaju morati odlučiti

which comet do we go for?

koju polovicu kometa dalje pratiti.

The lander -- again, lots of instruments,

Sonda za spuštanje -- ponovno, tu je puno instrumenata,

mostly comparable except for the things which hammer in the ground and drill, etc.

otprilike istih, osim stvari poput instrumenata za bušenje...

But much the same as Rosetta, and that is because you want to compare

Otprilike je sve isto kao i u Rosetti jer želite usporediti sve

what you find in space with what you find on the comet.

što nađete u svemiru s onim što nađete na kometu.

These are called ground truth measurements.

To se zove mjerenje na licu mjesta.

These are the landing descent images

Ovo su slike slijetanja

that were taken by the OSIRIS camera.

snimljenje kamerama OSIRIS.

You see the lander getting further and further away from Rosetta.

Vidite kako se sonda sve više i više udaljava od Rosette.

On the top right, you see an image taken at 60 meters by the lander,

Gore desno, vidite sliku koju je sonda snimila na 60 metara

60 meters above the surface of the comet.

od površine kometa.

The boulder there is some 10 meters.

Ona stijena ondje visoka je otprilike 10 metara.

So this is one of the last images we took before we landed on the comet.

To je jedna od zadnjih snimaka koje smo snimili prije slijetanja na komet.

Here, you see the whole sequence again, but from a different perspective,

Ovo je cijeli slijed ispočetka, ali iz drugog kuta

and you see three blown-ups from the bottom-left to the middle

i vide se tri uvećane snimke, od donjeg lijevog kuta prema sredini,

of the lander traveling over the surface of the comet.

sondinog leta iznad površine kometa.

Then, at the top, there is a before and an after image of the landing.

Na vrhu je slika prije i poslije slijetanja.

The only problem with the after image is, there is no lander.

Jedini problem sa slikom poslije slijetanja jest da se na njoj ne vidi sonda.

But if you carefully look at the right-hand side of this image,

Ali ako pažljivo pogledate desnu stranu slike

we saw the lander still there, but it had bounced.

vidjet ćete da je sonda još uvijek ondje, ali je odskočila.

It had departed again.

Uzletjela je ponovno.

Now, on a bit of a comical note here

Smiješno je u svemu tome

is that originally Rosetta was designed to have a lander which would bounce.

da je Rosettin izvorni nacrt predviđao sondu koja odskakuje.

That was discarded because it was way too expensive.

To je odbačeno jer je bilo preskupo.

Now, we forgot, but the lander knew.

Mi smo zaboravili, ali sonda nije.

(Laughter)

(Smijeh)

During the first bounce, in the magnetometers,

Prilikom prvog odraza, magnetometri su

you see here the data from them, from the three axes, x, y and z.

očitali i upisali podatke u tri osi: x, y i z.

Halfway through, you see a red line.

U sredini vidite crvenu liniju.

At that red line, there is a change.

Ta crvena linija pokazuje promjenu.

What happened, apparently, is during the first bounce,

Prilikom prvog odraza vjerojatno smo

somewhere, we hit the edge of a crater with one of the legs of the lander,

jednom nogom sonde negdje pogodili rub kratera

and the rotation velocity of the lander changed.

i promijenila se brzina rotacije sonde.

So we've been rather lucky

Tako da imamo sreću da smo

that we are where we are.

tu gdje smo sada.

This is one of the iconic images of Rosetta.

Ovo je jedna od povijesnih slika sa Rosette.

It's a man-made object, a leg of the lander,

Predmet koji je izradio čovjek, noga sonde,

standing on a comet.

stoji na kometu.

This, for me, is one of the very best images of space science I have ever seen.

Za mene je to najbolji prikaz znanosti u svemiru koji sam ikada vidio.

(Applause)

(Pljesak)

One of the things we still have to do is to actually find the lander.

Jedna od stvari koje još uvijek moramo napraviti jest pronaći sondu.

The blue area here is where we know it must be.

Znamo da se nalazi na jednome od ovih područja označenih plavom bojom.

We haven't been able to find it yet, but the search is continuing,

Nismo je još uspjeli naći, ali potraga se nastavlja,

as are our efforts to start getting the lander to work again.

kao i naši napori da sonda ponovno proradi.

We listen every day,

Slušamo svaki dan

and we hope that between now and somewhere in April,

i nadamo se da će se u periodu od sada do travnja

the lander will wake up again.

sonda ponovno probuditi.

The findings of what we found on the comet:

Otkrića do kojih smo došli na kometu:

This thing would float in water.

plutao bi u vodi.

It's half the density of water.

Ima upola manju gustoću od vode.

So it looks like a very big rock, but it's not.

Izgleda kao velika stijena, ali nije.

The activity increase we saw in June, July, August last year

Porast aktivnosti koji smo vidjeli u u lipnju, srpnju i kolovozu prošle godine

was a four-fold activity increase.

bio je četverostruk.

By the time we will be at the sun,

Prilikom prolaska kraj Sunca,

there will be 100 kilos a second leaving this comet:

komet će ispuštati 100 kilograma po sekundi:

gas, dust, whatever.

plina, prašine, čega god.

That's 100 million kilos a day.

To je 100 milijuna kilograma na dan.

Then, finally, the landing day.

I, konačno, dan slijetanja.

I will never forget -- absolute madness, 250 TV crews in Germany.

Nikad to neću zaboraviti -- totalno ludilo, 250 TV ekipa u Njemačkoj.

The BBC was interviewing me,

BBC me intervjuirao,

and another TV crew who was following me all day

a druga TV ekipa pratila me cijeli dan

were filming me being interviewed,

i snimala dok sam davao intervju.

and it went on like that for the whole day.

To je tako trajalo cijeli dan.

The Discovery Channel crew

Ekipa Discovery Channela

actually caught me when leaving the control room,

uhvatila me dok sam napuštao kontrolnu sobu.

and they asked the right question,

Postavili su mi pravo pitanje,

and man, I got into tears, and I still feel this.

i, čovječe, zaplakao sam. Još uvijek to osjećam.

For a month and a half,

Mjesec i pol

I couldn't think about landing day without crying,

nisam mogao o razmišljati o danu slijetanja bez suza

and I still have the emotion in me.

i još uvijek me drži taj osjećaj.

With this image of the comet, I would like to leave you.

Želio bih završiti s ovom slikom kometa.

Thank you.

Hvala.

(Applause)

(Pljesak)