The flower-shaped starshade that might help us detect Earth-like planets | Jeremy Kasdin

Prevoditelj: Ivan Stamenković Recezent: Senzos Osijek

The universe is teeming with planets.

Svemir je prepun planeta.

I want us, in the next decade,

Želim da mi, u sljedećem desetljeću

to build a space telescope that'll be able to image

izgradimo teleskop koji bi mogao uslikati

an Earth about another star

Zemlju kod druge zvijezde

and figure out whether it can harbor life.

i utvrditi može li podržati život.

My colleagues at the NASA Jet Propulsion Laboratory

Moje kolege u NASA-inom labosu za mlazni pogon

at Princeton and I are working on technology

na Princetonu i ja radili smo na tehologiji

that will be able to do just that in the coming years.

koja će moći baš to u dolazećim godinama.

Astronomers now believe that every star

Astronomi vjeruju da svaka zvijezda

in the galaxy has a planet,

u galaksiji ima planet,

and they speculate that up to one fifth of them

i procjenjuju da petina njih

have an Earth-like planet

ima planet sličan Zemlji

that might be able to harbor life,

koji bi mogao podržati život,

but we haven't seen any of them.

ali nismo vidjeli nijedan od njih.

We've only detected them indirectly.

Samo smo ih uočili indirektno.

This is NASA's famous picture of the pale blue dot.

Ovo je slavna NASA-ina slika blijede plave točke.

It was taken by the Voyager spacecraft in 1990,

Uslikao ju je Voyager 1990.,

when they turned it around as it was exiting the solar system

kada se okretao dok je izlazio iz sunčeva sustava

to take a picture of the Earth

kako bi uslikao Zemlju

from six billion kilometers away.

sa udaljenosti od šest milijardi kilometara.

I want to take that

Želim napraviti takvu sliku

of an Earth-like planet about another star.

planeta nalik Zemlji kod druge zvijezde.

Why haven't we done that? Why is that hard?

Zašto to nismo učinili? Zašto je to tako teško?

Well to see, let's imagine we take

Pa da vidimo, zamislimo da uzmemo

the Hubble Space Telescope

Hubble Svemirski Teleskop

and we turn it around and we move it out

i okrenemo ga i pomaknemo

to the orbit of Mars.

do orbite Marsa.

We'll see something like that,

Vidjet ćemo nešto poput toga,

a slightly blurry picture of the Earth,

pomalo mutnu sliku Zemlje,

because we're a fairly small telescope

jer smo poprilično mali teleskop

out at the orbit of Mars.

u orbiti Marsa.

Now let's move ten times further away.

Udaljimo se deset puta više.

Here we are at the orbit of Uranus.

Sada smo kod orbite Urana.

It's gotten smaller, it's got less detail, less resolve.

Postala je manja, ima manje detalja, manju razlučivost.

We can still see the little moon,

Još uvijek možemo vidjeti mali mjesec,

but let's go ten times further away again.

no idemo još deset puta dalje.

Here we are at the edge of the solar system,

Sada smo na rubu Sunčevog sustava,

out at the Kuiper Belt.

kod Kuiperovog pojasa.

Now it's not resolved at all.

Sada nema razlučivosti.

It's that pale blue dot of Carl Sagan's.

To je ona plava točka Carla Sagana.

But let's move yet again ten times further away.

Ali udaljimo se još deset puta.

Here we are out at the Oort Cloud,

Sada smo kod Oort oblaka,

outside the solar system,

izvan Sunčevog sustava,

and we're starting to see the sun

i počinjemo vidjeti Sunce

move into the field of view

kako ulazi u vidno polje

and get into where the planet is.

i dolazi na mjesto gdje je planet.

One more time, ten times further away.

Još jednom, deset puta dalje.

Now we're at Alpha Centauri,

Sada smo kod Alpha Centauri,

our nearest neighbor star,

nama najbliže zvijezde,

and the planet is gone.

i planet je nestao.

All we're seeing is the big beaming image of the star

Sve što vidimo je velika blješteća slika zvijezde

that's ten billion times brighter than the planet,

koja je deset milijardi puta sjajnija od planeta,

which should be in that little red circle.

koji bi trebao biti u onom malom crvenom kružiću.

That's what we want to see. That's why it's hard.

To je ono što želimo vidjeti. Zato je teško.

The light from the star is diffracting.

Svjetlo zvijezde se defraktira.

It's scattering inside the telescope,

Raspršuje se unutar teleskopa,

creating that very bright image

stvarajući vrlo svijetlu sliku

that washes out the planet.

koja ispire planet.

So to see the planet,

Tako da bismo vidjeli planet,

we have to do something about all of that light.

moramo učiniti nešto vezano uz to svjetlo.

We have to get rid of it.

Moramo ga se riješiti.

I have a lot of colleagues working on

Imam puno kolega koji rade na

really amazing technologies to do that,

zaista odličnim tehnologijama kako bi to napravili,

but I want to tell you about one today

ali danas vam želim pričati o jednoj

that I think is the coolest,

koja je stvarno najbolja,

and probably the most likely to get us an Earth

i možda najizglednija da nam pribavi Zemlju

in the next decade.

u sljedećem desetljeću.

It was first suggested by Lyman Spitzer,

Prvo ju je predložio Lyman Spitzer,

the father of the space telescope, in 1962,

otac svemirskog teleskopa, 1962.,

and he took his inspiration from an eclipse.

i dobio je inspiraciju iz pomrčine.

You've all seen that. That's a solar eclipse.

Svi ste to vidjeli. To je pomrčina Sunca.

The moon has moved in front of the sun.

Mjesec se pomaknuo ispred Sunca.

It blocks out most of the light

Blokira većinu svjetla

so we can see that dim corona around it.

tako da možemo vidjeti prigušeni vijenac oko njega.

It would be the same thing if I put my thumb up

Ista stvar bi bila da stavim palac

and blocked that spotlight that's getting right in my eye,

i blokiram to svjetlo koje dolazi u moje oko,

I can see you in the back row.

vidim vas u stražnjem redu.

Well, what's going on?

Pa, što se događa?

Well the moon

Mjesec

is casting a shadow down on the Earth.

baca sjenu na Zemlju.

We put a telescope or a camera in that shadow,

Stavimo li teleskop ili kameru u tu sjenu,

we look back at the sun,

gledamo na Sunce,

and most of the light's been removed

i većina svjetla je uklonjena

and we can see that dim, fine structure

i možemo vidjeti tu prigušenu, finu strukturu

in the corona.

u vijencu.

Spitzer's suggestion was we do this in space.

Spitzerov prijelog je bio da ovo učinimo u svemiru.

We build a big screen, we fly it in space,

Izgradimo veliki zaslon, lansiramo ga u svemir,

we put it up in front of the star,

stavimo ga ispred zvijezde,

we block out most of the light,

blokiramo većinu svjetla,

we fly a space telescope in that shadow that's created,

lansiramo teleskop u sjenu koju je stvorio,

and boom, we get to see planets.

i bum, vidimo planete.

Well that would look something like this.

To bi izgledalo otprilike ovako.

So there's that big screen,

Tu je taj veliki zaslon,

and there's no planets,

because unfortunately it doesn't actually work very well,

i nema planeta,

jer na nesreću ne radi vrlo dobro,

because the light waves of the light and waves

jer se valovi svjetlosti i svjetlo i valovi

diffracts around that screen

raspršuju oko zaslona

the same way it did in the telescope.

isto kao u teleskopu.

It's like water bending around a rock in a stream,

To je kao da se voda uvija oko kamena u potoku,

and all that light just destroys the shadow.

i svo to svjetlo jednostavno uništava sjenu.

It's a terrible shadow. And we can't see planets.

To je užasna sjena. I ne možemo vidjeti planete.

But Spitzer actually knew the answer.

Ali Spitzer je znao odgovor.

If we can feather the edges, soften those edges

Ako možemo omekšati rubove, učiniti ih paperjastima

so we can control diffraction,

tako da možemo kontrolirati rasipanje,

well then we can see a planet,

onda možemo vidjeti planet,

and in the last 10 years or so we've come up

i u zadnjih 10 godina došli smo do

with optimal solutions for doing that.

optimalnog rješenja da to učinimo.

It looks something like that.

Izgleda otprilike ovako.

We call that our flower petal starshade.

Zovemo to zvjezdasta sjenica u obliku cvijeta.

If we make the edges of those petals exactly right,

Ako napravimo rubove tih latica kako treba,

if we control their shape,

ako kontroliramo njihov oblik,

we can control diffraction,

možemo kontrolirati rasipanje,

and now we have a great shadow.

i sada imamo odličnu sjenu.

It's about 10 billion times dimmer than it was before,

To je 10 milijardi puta prigušenije nego je bilo prije,

and we can see the planets beam out just like that.

i možemo vidjeti kako se pojavljuju planeti.

That, of course, has to be bigger than my thumb.

To bi naravno moralo biti veće od mog palca.

That starshade is about

Ta zvjezdasta sjenica je otprilike

the size of half a football field

veličine pola nogometnog igrališta

and it has to fly 50,000 kilometers away from the telescope

i mora letjeti 50000 kilometara od teleskopa

that has to be held right in its shadow,

koji mora biti točno u njenoj sjeni,

and then we can see those planets.

i onda možemo vidjeti planete.

This sounds formidable,

To zvuči zastrašujuće,

but brilliant engineers, colleagues of mine at JPL,

ali briljantni inžinjeri, moji kolege na JPL-u [Laboratorij za Mlazni Pogon]

came up with a fabulous design for how to do that

smislili su odličan dizajn kako bi to napravili

and it looks like this.

i izgleda ovako.

It starts wrapped around a hub.

Započinje omotan oko osnove.

It separates from the telescope.

Odvaja se od teleskopa.

The petals unfurl, they open up,

Latice se razmataju, otvaraju se,

the telescope turns around.

teleskop se okreće.

Then you'll see it flip and fly out

Onda ćete ju vidjeti kako se preokreće i odlijeće

that 50,000 kilometers away from the telescope.

tih 50000 kilometara od teleskopa

It's going to move in front of the star

Pomaknut će se ispred zvijezde

just like that, creates a wonderful shadow.

baš tako, stvarajući divnu sjenu.

Boom, we get planets orbiting about it.

Bum, dobijemo planete koji se kreću oko zvijezde.

(Applause)

(Pljesak)

Thank you.

Hvala vam.

That's not science fiction.

To nije znanstvena fantastika.

We've been working on this for the last five or six years.

Radimo na tome posljednjih pet ili šest godina.

Last summer, we did a really cool test

Prošlog ljeta napravili smo test

out in California at Northrop Grumman.

u Kaliforniji, na Northrop Grummanu.

So those are four petals.

Ove su četiri latice.

This is a sub-scale star shade.

Ovo je manja zvjezdasta sjenica.

It's about half the size of the one you just saw.

Velika je upola kao ona što ste vidjeli.

You'll see the petals unfurl.

Vidjet ćete kako se latice odmataju.

Those four petals were built by four undergraduates

Te četiri latice izgradila su četiri preddiplomca

doing a summer internship at JPL.

dok su bila na praksi.

Now you're seeing it deploy.

Sad ćete vidjeti kako se pokreću.

Those petals have to rotate into place.

Te latice se moraju zarotirati na mjesto.

The base of those petals

Baza ovih latica

has to go to the same place every time

mora ići na isto mjesto svakog puta

to within a tenth of a millimeter.

sa točnošću od desetine milimetra.

We ran this test 16 times,

Radili smo ovaj test 16 puta,

and 16 times it went into the exact same place

i 16 puta je došao na potpuno isto mjesto

to a tenth of a millimeter.

u desetinu milimetra.

This has to be done very precisely,

Ovo mora biti učinjeno vrlo precizno,

but if we can do this, if we can build this technology,

ali ako to možemo učiniti, ako možemo izgraditi ovu tehnologiju,

if we can get it into space,

ako možemo to poslati u svemir,

you might see something like this.

možda ćete vidjeti nešto poput ovoga.

That's a picture of one our nearest neighbor stars

To je slika jedne od naših najbližih susjednih zvijezda

taken with the Hubble Space Telescope.

uslikana sa Hubble Svemirskim Teleskopom.

If we can take a similar space telescope,

Ako možemo sličan teleskop,

slightly larger,

malo veći,

put it out there,

poslati u svemir,

fly an occulter in front of it,

poslati zaklanjač ispred njega,

what we might see is something like that --

ono što bi mogli vidjeti je nešto poput toga --

that's a family portrait of our solar system -- but not ours.

to je obiteljski portret našeg Sunčevog sustava -- ali ne našeg.

We're hoping it'll be someone else's solar system

Nadamo se da će to biti tuđi Sunčev sustav

as seen through an occulter,

viđen kroz zaklanjač,

through a starshade like that.

kroz zvjezdastu sjenicu.

You can see Jupiter, you can see Saturn,

Možete vidjeti Jupiter, Saturn,

Uranus, Neptune, and right there in the center,

Uran, Neptun i tamo u središtu,

next to the residual light

blizu ostataka svjetlosti

is that pale blue dot. That's Earth.

je ta plava blijeda točka. To je Zemlja.

We want to see that, see if there's water,

Želimo to vidjeti, ima li vode,

oxygen, ozone,

kisika, ozona,

the things that might tell us that it could harbor life.

stvari koje bi nam mogle reći da može podržavati život.

I think this is the coolest possible science.

Mislim da je ovo najbolja moguća znanost.

That's why I got into doing this,

Zato sam se time počeo baviti,

because I think that will change the world.

jer mislim da će to promijeniti svijet.

That will change everything when we see that.

To će promijeniti sve kada to vidimo.

Thank you.

Hvala vam.

(Applause)

(Pljesak)