Will future spacecraft fit in our pockets? - Dhonam Pemba

Hoće li nam u budućnosti svemirski brodovi stati u džep?- Dhonam Pemba

Prevoditelj: Vanja Kovac Recezent: Ivan Stamenković

When you picture a spaceship, you probably think of something like this,

Kada zamišljate svemirski brod, vjerojatno zamišljate nešto ovako,

or this, or maybe this.

ili ovako, ili možda ovako.

What do they all have in common?

Što im je zajedničko?

Among other things, they're huge because they have to carry people, fuel,

Između ostalog, ogromni su zato što moraju nositi ljude, gorivo,

and all sorts of supplies, scientific instruments,

razne potrepštine, znanstvene instrumente,

and, in rare cases, planet-killing lasers.

i, u rijeđim slučajevima, lasere koji uništavaju planete.

But the next real-world generation of spacecraft may be much, much smaller.

Ali sljedeća generacija svemirskih brodova može biti puno, puno manja.

We're talking fit-inside-your-pocket tiny.

Govorimo o stane-ti-u-džep malom.

Imagine sending a swarm of these microspacecraft out into the galaxy.

Zamisilte slanje roja takvih mikrobrodova u galaksiju.

They could explore distant stars and planets

Mogli bi istraživati udaljene zvijezde i planete

by carrying sophisticated electronic sensors

noseći sofisticirane elektronske senzore

that would measure everything from temperature to cosmic rays.

koji bi mjerili sve od temperature do kozmičkih zraka.

You could deploy thousands of them

Možete poslati tisuće takvih

for the cost of a single space shuttle mission,

u trošku jedne misije space shuttlea,

exponentially increasing the amount of data

eksponencijalno povećavajuči količinu podataka

we could collect about the universe.

koju bi mogli prikupiti o svemiru.

And they're individually expendable,

I oni su individualno potrošni,

meaning that we could send them into environments

što znači da ih možemo poslati u okoliše

that are too risky for a billion dollar rocket or probe.

koji su preopasni za raketu ili sondu koja košta milijune dolara.

Several hundred small spacecraft are already orbiting the Earth,

Neoliko sotina malih svemirskih brodova već kruži oko Zemlje,

taking pictures of outer space,

i slika svemir,

and collecting data on things,

i skuplja podatke o stvarima,

like the behavior of bacteria in the Earth's atmosphere

kao što su ponašanje bakterija u zemljinoj atmosferi

and magnetic signals that could help predict earthquakes.

ili magnetni signali koji mogu pomoći predvidjeti potrese.

But imagine how much more we could learn if they could fly beyond Earth's orbit.

Ali zamislite koliko bismo mogli naučiti kada bi oni letjeli van zemljine orbite.

That's exactly what organizations, like NASA, want to do:

To je točno ono što organizacije kao NASA žele napraviti:

send microspacecraft to scout habitable planets

poslati mikrobrodove tražiti naseljive planete

and describe astronomical phenomena we can't study from Earth.

i opisivati astronomske fenomene koje ne možemo proučavati sa Zemlje.

But something so small can't carry a large engine or tons of fuel,

Ali nešto tako malo ne može nositi veliki motor i tone goriva,

so how would such a vessel propel itself?

kako bi se takav brod pokretao?

For microspacecraft, it turns out, you need micropropulsion.

Za mikrobrod, ispada, potreban ti je mikropogon.

On really small scales,

Na stvarno malim mjerilima

some of the familiar rules of physics don't apply,

neki od poznatih zakona fizike nisu primjenjivi,

in particular, everyday Newtonian mechanics break down,

posebno, svakodnevna Newtonova mehanika pada u vodu,

and forces that are normally negligible become powerful.

a sile koje su inače zanemarive, postanu moćne.

Those forces include surface tension and capillary action,

Te sile uključuju površinsku napetost i kapilarno djelovanje,

the phenomena that govern other small things.

fenomene koji upravljaju malim stvarima.

Micropropulsion systems can harness these forces to power spacecraft.

Sustav mikropogona može prikupljati te sile kako bi pokretao brod.

One example of how this might work

Primjer kako bi to moglo raditi

is called microfluidic electrospray propulsion.

je mikrofluidičk elektro pogon.

It's a type of ion thruster,

To je tip ionskog pogona,

which means that it shoots out charged particles to generate momentum.

što znači da ispaljuje nabijene čestice da napravi zamah.

One model being developed at NASA's jet propulsion laboratory

Jedan takav model razvija se u NASAinom pogonskom laboratoriju

is only a couple centimeters on each side.

i ima samo nekoliko centimetara sa svake strane.

Here's how it works.

Evo kako radi.

That postage-stamp sized metal plate is studded with a hundred skinny needles

Ta metalna pločica veličine poštanske marke okovana je stotinama tankih iglica

and coated with a metal that has a low melting point, like indium.

i premazana metalom koji ima nisko talište, kao Indij.

A metal grid sits above the needles,

Metalna rešetka nalazi se iznad iglica,

and an electric field is set up between the grid and the plate.

i električno polje je postavljeno između rešetke i pločice.

When the plate is heated, the indium melts

Kada se pločica ugrije, Indij se otopi

and capillary action draws the liquid metal up the needles.

i kapilarno djelovanje privlači tekući metal na iglice.

The electric field tugs the molten metal upwards,

Elektirčno polje vuče otopljeni metal gore,

while surface tension pulls it back,

dok ga napetost površine vuče dolje,

causing the indium to deform into a cone.

uzrokujući da se Indij deformira u stožac.

The small radius of the tips of the needles

Mali promjer vrhova iglica

makes it possible for the electric field to overcome the surface tension,

omogućuje da električno polje prevlada površinsku napetost,

and when that happens,

a kada se to dogodi,

positively charged ions shoot off at speeds of tens of kilometers per second.

pozitivno nabijeni ioni ispaljuju se brzinom od nekoliko desetaka kilometara u sekundi.

That stream of ions propels the spacecraft in the opposite direction,

Taj mlaz iona pokreće brod u suprotnom smjeru,

thanks to Newton's third law.

zahvaljujući Newtonovom trećem zakonu.

And while each ion is an extremely small particle,

I dok je jedan ion iznimno mala čestica,

the combined force of so many of them pushing away from the craft

kombinirana sila toliko njih koji se odguruju od broda

is enough to generate significant acceleration.

dovoljna je da stvori značajno ubrzanje.

And unlike the exhaust that pours out of a rocket engine,

I za razliku od ispuha koji ide iz motora rakete,

this stream is much smaller and far more fuel efficient,

ovaj mlaz je puno manji i puno učinkovitiji što se tiče goriva,

which makes it better suited for long deep-space missions.

što ga čini prihvatljivijim za duge misije duboko u svemir.

These micropropulsion systems haven't been fully tested yet,

Ovi sustavi mikropogona još nisu u potpunosti testirani,

but some scientists think that they will provide enough thrust

ali neki znanstvenici smatraju da će omogućiti dovoljno pogona

to break small craft out of Earth's orbit.

da se mali brodovi probiju van Zemljine orbite.

In fact, they're predicting that thousands of microspacecraft

Zapravo, predviđaju da će tisuće mikrobrodova

will be launched in the next ten years

biti lansirane u sljedećih 10 godina

to gather data that today we can only dream about.

kako bi skupili podatke o kojima danas možemo samo sanjati.

And that is micro-rocket science.

I to je mikro - raketna znanost.