Kako će ljudi osvojiti Mars i šire

How humans will conquer Mars and beyond

 

Powered by Guardian.co.ukOvaj članak pod naslovom “Kako će ljudi osvojiti Mars i šire” je napisao Kevin Fong, za The Observer u nedjelju 13. decembar 2015 08.30 UTC

Ove godine Royal Institution Božićni Predavanja pogledati na izazov ljudskih svemirskih letova i ono što je potrebno da se baci ljude u krajnja granica na putovanjima istraživanja.

Kao liječnik sam proveo više od deset godina putuje natrag i naprijed između Velike Britanije i NASA Johnson Space Center u Houston, radi kao gostujući istraživač na projektima u rasponu od proučavanja efekata prostora okruženja na starenje fiziologiju na veštačke gravitacije sisteme. U isto vrijeme sam bio završetka moje junior medicinske obuke u anesteziji i intenzivnoj njezi. Bilo je čudno pokušava da uplitanje ta dva života zajedno. Rad na jedinici intenzivne njege preko noći, ka aerodromu na kraju smjene, hvatajući malo sna u avionu, a onda dolaze sutradan u sobi za sastanke u Houston, gdje su ljudi sedeli pričaju o tome kako da pošalje ljude sigurno na Mars.

Ali ono što je povezivao dva bio je izazov života u ekstremnim. U bolnici sam gledao krajnosti života kada osporavaju bolesti i ozljede. NASA Gledao sam prijetnja ljudskoj fiziologiji do krajnosti fizičkog svijeta i svemira.

Kada govorimo o ekstremnim uvjetima možemo dobiti grubu ideju njihove štednje po sudeći koliko dugo će oni podržati ljudski život nezaštićeni i bez podrške. Do te mjere prostora je krajnji ekstremni: jedinstveno neprijateljski na ljudsku fiziologiju, to ne pruža podršku za bilo ljudski život. Nezaštićene svemirskog putnika opstati u tom okruženju samo nekoliko sekundi.

Možda ćete zamisliti da će biti dovoljno za doktora da uradi - da, kada je riječ o istraživanju ljudskih prostor, ljudi koji razumiju i mogu manipulirati ljudsku fiziologiju će biti na čelu tog napora. Ali, lekari imaju loš druga violina na ono što je većinom kulturu inženjering - i to sa dobrim razlogom.

Space Flight je u fizičkom principu razoružavajuće jednostavan. Tako jednostavno u činjenici da je Njutn počeo da shvate dinamiku da podupiru gotovo 400 prije mnogo godina. Da napuste Zemlju i unesite orbitu oko njega, prvo morate baciti predmet širom svijeta tako jako da je njegova putanja se prostire izvan Zemljine horizonata - tako jako da može biti da padne na takav način da se više nikada ne pronalazi tlo.

I tako da stavi predmet u orbitu oko Zemlje morate ga pružiti ogromnu količinu energije. U širem smislu brže idete šire radijus orbite da postignete; da se vozilo kako bi se postigla orbitu dovoljno širok da ga propustiti i Zemlju i gornje slojeve atmosfere, da vas na istoj visini kao i Međunarodne svemirske stanice neki 250 kilometara iznad nas, putuje oko 17,500mph.

To zahtijeva vozilo pokreće motor i rezervoar za gorivo sa eksplozivnim kapaciteta malog nuklearnog oružja. ovaj put, od površine Zemlje u niskoj orbiti oko Zemlje - na brodu Sojuz - potrebno je nešto više od osam minuta. I tako je razlog da je kultura na Nasa, i svemirskih agencija širom svijeta, je tako čvrsto ukorijenjena u zahtjevima inženjeringa, a ne one ljudske biologije je zato što u tom kratkom, ali nasilan period ne postoji gotovo ništa moderna medicina može ponuditi na način zaštite. tokom lansiranja, bilo građevinskih radova i svi su živi, ili se to ne desi i svi nestaje.

Očuvanje ljudskog života u cijeloj lansiranje ovisi ne na medicinske postupke, ali na koncentrične slojeve umjetnih zaštite koji inženjeri dizajn i izgraditi i poviti astronauta posade u.

U raketnih motora mora otpustiti savršeno, pružajući samo pravo potisak u pravom trenutku, usmjerena u upravo pravi način. Ogromna snaga da pogon ne smije se dozvoliti da uzdrma vozilo, svojih sistema ili njegovih krhki teret putnika, osim. To je posao inženjerskih timova kako bi bili sigurni da je pokretač i vozila su dizajnirani za obavljanje u lice snaga koje pokušavaju da ih uništiti.

I sede na vrhu da toranj kerozina i kisika je mala kapsula, sa obimom od nekoliko telefonskih govornica, i nekoliko tona materijala i tri putnika zbijeni u među njima. To kapsula je mali balon života podrške, uklještenja off od Zemlje i održava umjetno. Unutra, još više strojevi pružaju prozračna atmosfera sa dovoljno pritiska i topline da podrži život u praznini prostora. Ako preživi lansiranje, vaše probleme zaista tek počinju.

Chris Hadfield na ISS
Visoki stol: Chris Hadfield jedu u bestežinskom stanju na brodu na Međunarodnu svemirsku stanicu. Fotografija: na

Međunarodne svemirske stanice

To je primamljivo misliti na Međunarodnoj svemirskoj stanici kao hi-tech Veliki brat kuća, plutajući visoko iznad Zemlje. U nekom smislu to je istina: uslovi za život su oštre na bilo koji normalan standard. Postoji nekoliko stvorenje udobnost i vrlo malo privatnosti. To je živi aranžman načičkanih potencijal za ogromne socijalne sukoba. Ali izuzetno koji je u velikoj mjeri izbjeći i na 15 godina rada nije bilo iseljavanja.

Ali ISS je mnogo više nego smještaj blok. Kada posada ode da živi tamo uzimaju se prebivalište unutar mašine na kojima su njihovi životi zavise od svakog drugog dana. Oni Electrolyse vode za proizvodnju kisika, zapošljavaju molekularna sita češe otpadnih plinova iz zraka koji dišu, pokrenuti sistema grijanja od ogromne solarne nizova koji se mogu ispumpati 80kW snage. To solarne energije i pokreće četiri ogromne žiroskopa, koji stabilan i upravljati stanice, sprečava njeno prevrtanje van kontrole.

Međunarodne svemirske stanice je daleko od miran: to bruji i pekmezi neprestano; navijači rade cijelo vrijeme. Bez gravitacije topli zrak ne raste i hladan zrak ne potone. Tu je, kao posljedica, ne konvekcijom i bez da je teško da se zrak za pomicanje ili mix. That in turn causes problems, leaving astronauts prone to headaches in poorly ventilated areas, where exhaled carbon dioxide can build up. Hence the constant drum of motors churning air. The draughts on the ISS, like almost everything else that the crews depend upon for healthy living, are artificial. All of this effort just to maintain that bubble of life support in an outpost just 250 miles above our heads. The challenges involved are legion and we haven’t even started to talk about leaving low Earth orbit yet.

Back to the moon

There is unfinished business on the moon. It is nearly half a century since the Apollo programme landed a dozen men on its surface. And while it represents a treasure trove of scientific discovery, nobody has been back since. Low Earth orbit is 250 milja daleko i može se doći za nekoliko minuta. Mesec je oko 250,000 miljama daleko, potrebni dani da se na i, Osim izolacije i dodao složenosti rakete nauke potrebne, ostavlja posade izuzetno osjetljivi na zračenje. Na Zemlji smo zaštićeni od nekih vrsta zračenja debelih pokrivač atmosfere iznad, koji upija gama zraka, x-zrake i ultraljubičastog zračenja koji bi inače bili štetni. Ali postoji još jedan sloj zaštite koji se čuva nas sigurno: Zemljino magnetno polje.

Magnetosferu filtrira posebno štetna vrsta zračenja, koji dolazi u obliku naplaćuje, visoko-energetske čestice - atomska jezgra ispljunuo kao nusproizvod termonuklearne reakcije u zvezdica uključujući i našu. Ova vrsta zračenja je posebno štetan i, during solar flares, can increase in intensity by many thousands of times. Presently we have little in the way of effective protection from the radiation that comes with the worst solar flares.

Mars and beyond

In recent years the idea of putting human crews on the surface of something other than the moon or Mars has found its way into the strategy documents of the international space agencies. This mission is less science fiction than you might think. The European Space Agenecy’s Rosetta mission, which so spectacularly landed the Philae lander on the surface of a comet last year, showed us that we could find and intercept a tiny target hurtling through space hundreds of billions of miles away. This has given agencies confidence that their idea of landing a human crew on an asteroid might be realisable.

But for now it is Mars that lies at the edge of possibility, and surviving that journey presents a challenge on a different scale. With Mars, the problem is distance and time. To get to the red planet you have to traverse hundreds of millions of interplanetary miles; više nego 1,000 times the distance Apollo crews travelled to the moon. With existing technology it would take between six and nine months to travel from Earth to Mars and the same again on the return leg.

That’s a lot of time spent without any gravitational load on your body. Weightlessness may look like fun, but like everything else, too much of it can be a bad thing. When physiologists first considered what effect the space environment might have on the human body, before anybody had even been into space, they correctly predicted that muscle and bone would waste. Those systems are sculpted by gravity and as anyone who has ever so much as looked at a gym knows, if you don’t use it you lose it. Zbog ovoga, crews aboard the International Space Station must subject themselves to a daily programme of resistive exercise to try and prevent some of that bone and muscle loss.

the surface of mars
Was there life on Mars? Dark streaks on the planet’s surface which seem to indicate the presence of flowing water. Fotografija: Nasa/Reuters

Weightlessness wreaks havoc with other systems. It upsets your senses of balance and co-ordination, making it more difficult for crew members to track moving targets, creating illusions of motion and, for the first few days of flight, generally making them feel pretty queasy. With the exception of the nausea, all of these problems tend to get worse the longer you spend weightless.

Skorije, new – and potentially more worrying – problems have cropped up. For reasons that are not yet entirely clear the pressure in some astronauts’ brains appears to rise as a consequence of space flight, and this has been linked to alterations in their eyesight that sometimes persist for many years after their return to Earth. This phenomenon has only been noticed after long duration missions, which highlights the message: spending a lot of time in space isn’t great for your health.

But time also creates problems for life support systems. If you imagine the amount of food, voda, oxygen and power a single person might consume in a mission set to last up to three years (if you include the surface stay), that demands quite a sizable larder. Now multiply that by a crew of four or six and it looks like you need an impossibly huge spacecraft just to keep you fed and watered.

And that does become impossible unless you are able to recycle and reuse everything you can. Already aboard the space station astronauts recycle most of their waste water, including their urine. They scrub carbon dioxide out of their exhaled air and rebreathe the remaining oxygen. You might be able to go further still, by growing crops hydroponically, as a source of food and a mechanism of removing carbon dioxide and renewing the oxygen supply. If you choose the right plants you might even recycle the nitrogen in human solid waste. Which of course is a scientific way of saying that maybe you could use your own poo to fertilise your life-supporting crops.

A system as sophisticated as that is extremely difficult to assemble, manage and maintain, and it’s likely to be a while before we see greenhouses flying through deep space. For now life support engineers will content themselves with finding ways to recycle more and more of the resources they can, and in so doing reducing the amount of payload that crews have to set aside for the things that keep them alive.

There is a simple lesson from all of this: space is hard. All frontier endeavours are. But there is plenty to celebrate here. Since the start of the 21st century there has been a permanent human presence in space. What started as a surrogate battlefield for nuclear war has become a multinational programme of science, exploration and collaboration. This is not the place to get into a discussion of why we should explore space at all. There are many benefits that derive from human space exploration but one is more important than all the rest. Human space exploration inspires children to study and pursue careers in science, technology and engineering. It does so by showing them that within the limits of human imagination anything might be possible. I know this because it inspired me and throughout the whole of my life has continued to hold my fascination.

It is an enormous honour to give the Royal Institution’s Christmas Lectures. And yes, the take-home message is that space is hard. But the real lesson for this year’s audience is that this has been my adventure and it can be yours too.

How to Survive in Space will be shown on BBC4 in three parts on 28, 29 i 30 December at 8pm. Find out more on the Royal Institution’s website and join the conversation on Twitter and Instagram by following @ri_science or searching for #xmaslectures

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