HaveyoueverdreamedofvisitingaplanetintheMilkyWay(银河系)?Whilethetripsoundsexcitingitwouldtakeyearsandyearstoreachyourdestination.Sointhefuturebedtimeforastronautsmaybemorethanafewhoursofregularshuteye.Theywouldhavetosleepforyears.

Europeanresearchersarenowconductinghibernationexperiments.Thestudymayhelpthemunderstandwhetherhumanscouldeversleepthroughtheyearsitwouldtakeforaspaceflighttodistantplanets."Iftherewasaneffectivetechnologyitcouldmakedeep-spacetravelareality"saidMarkAyreoftheEuropeanSpaceAgencylastmonth.

Whatseemslikeasciencefictionisnotcompletelyunlikely.Researchershavebeenabletousechemicalstoputlivingcellsintoasleep-likestatewheretheydon’tage.Theyhavenowmovedontothesmallnon-hibernatingmammals(哺乳动物)likerats.

Amajorchallengeisthefactthatcellscanbeverysimplesystemswhereasbodyorgansarefarmorecomplex(复杂的)."It’slikemovingfromasimpleApplecomputertoasupercomputer"saidMarcoBiggiogeraahibernationresearcheratItaly’sUniversityofPavia．Justlikebearsandfrogsthehibernationofhumanbeingswouldcauseaperson’smetabolism(新陈代谢)tolowersotheywouldneedlessenergy.

Medicalresearchhoweverisjusthalfofaspaceflighthibernationsystem.Thereisachallengeofdesigningasuitableprotectiveshelter(栖身所).Suchashelterwouldprovidetheproperenvironmentforhibernationsuchasthepropertemperature.Itwouldalsohavetomonitor(监控)lifefunctionsandservethephysiologicalneedsofthehibernator.

AccordingtoAyrethesix-personHumanOuterPlanetsExplorationMission(使命)toJupiter’smoon(木星的卫星)Callistocouldbeanopportunitytousehumanhibernation.Themissionaimstosendsixpersonsonafive-yearflighttoCallistowheretheywillspend30daysin2045.

Accordingtothearticlethehibernationresearch______.

A．isjustanidea B．isalwaysasciencefiction

C．hasalreadyfinishedsuccessfully D．hasmadesomeprogress

Inahibernatingstateapersonneeds______.

A．lesssleep B．morefood C．lessenergy D．moremovement

Thefirsttryofthehibernationtechno