OUT THERE
Discovery Rekindles Wish for a Journey to the Stars
By DENNIS OVERBYE October 29, 2012
新發現行星重燃星際旅行熱
DENNIS OVERBYE 報道 2012年10月29日
What will you wear to Alpha Centauri?
你會穿什么衣服去半人馬座阿爾法星系(Alpha Centauri)?
The news last week that there is a planet circling Alpha Centauri B, only a little more than four light-years away, set off an epidemic of daydreaming among the astronomical and sci-fi set, me among them.上周，新聞報道稱，發現了一顆圍繞半人馬座阿爾法B星(Alpha Centauri B)運轉的行星，它距離我們只有四光年多一點。這一發現令天文學家和科幻迷不禁為之神往，我也是其中一員。
For people who believe that interstellar voyages, either for people or for robots, are in the future, Alpha Centauri, a triple-star system that is the
Sun’s nearest known neighbor, has always loomed large and close as a destination. It was the home of the mythical jungle world Pandora in James Cameron’s epic “Avatar,” for example.半人馬座阿爾法星系是一個三恒星系統，也是距離太陽系最近的已知恒星系。對那些相信人類或者機器人將在未來展開星際旅行的人來說，這個星系一直是一個遙遙在望的目的地，引人矚目。例如，詹姆斯·卡梅隆(James Cameron)執導的史詩巨片《阿凡達》(Avatar)當中，那個神話般的叢林秘境潘多拉星球(Pandora)，就在半人馬座阿爾法星系。
Elwood H. Smith
The new planet doesn’t have jungles, giant blue-skinned cats or, as far as we know, the magical mineral unobtainium. It is, rather, a hellish unlivable blob of lava probably about the size of Earth, only four million short miles from the fires of Alpha Centauri B, the second brightest star in the system.這顆新發現的行星上沒有叢林，也沒有藍色皮膚的大貓。至少據我們現在所知，那里也沒有神奇的礦物難得素（《阿凡達》中產自潘多拉星的礦物質——譯注)。相反，它是一個巖漿橫流、環境極端嚴酷的星球，大小可能與地球相仿，距離半人馬座阿爾法星系第二亮星——半人馬座阿爾法B星噴發的熱焰，只有短短400萬英里(約合643萬公里)。
But if astronomers have learned anything over the last few years from devices like the
Kepler satellite, it is that small planets come in packs. There is plenty of room in the system for more planets, habitable ones.不過，如果天文學家在過去幾年中已通過像開普勒衛星(Kepler satellite)這樣的探測工具了解到任何規律，那就是，小型的行星總是集群出現。半人馬座阿爾法星系有足夠的空間容納更多的行星，包括宜居的行星。
“I think we should drop everything and send a probe there,” said Sara Seager, an astronomer at M.I.T., echoing a call made last year by the exoplanet pioneer Geoff Marcy of the University of California, Berkeley.麻省理工學院(MIT)天文學家薩拉·西格(Sara Seager)說，“我認為，我們應當放下手邊的一切事務，向這個行星發射探測器?！彼挠^點呼應了加利福尼亞大學伯克利分校(University of California, Berkeley)系外行星先鋒派學者杰夫·馬西(Geoff Marcy)的呼吁。
There is in fact somebody in charge of doing something just like that. Her name is Mae Jemison, a former astronaut, engineer, dancer, actor and entrepreneur. This year she, in conjunction with the nonprofit foundation Icarus Interstellar, won a $500,000 government grant to set up 100 Year Starship, an organization that is to come up with a business plan for interstellar travel.實際上，確實有人在負責類似計劃的實施。她的名字是梅·杰米森(Mae Jemison)，她是一位前宇航員、工程師、舞蹈家、演員和企業家。今年，她聯合非營利基金會伊卡洛斯星際組織(Icarus Interstellar)，獲得了50萬美元（約合315萬元人民幣）的政府經費，用以建立百年星艦(100 Year Starship)組織。這個組織將拿出一個星際旅行的商業計劃。
Darpa, the government agency that helped invent the Internet and now wants to help invent interstellar travel, estimated that just planning for such a trip could take 100 years. Dr. Jemison, 56, hopes it can happen sooner.曾經幫助發明了互聯網的美國國防部高級研究計劃局（Defense Advanced Research Projects Agency，簡稱Darpa)現在想幫助開發星際旅行。計劃局預計，僅僅是規劃這樣的旅行就要花費100年時間。56歲的杰米森希望這樣的旅程能盡早成真。
The Centauri planet was officially announced on her birthday, and over the phone from her new headquarters in Houston she sounded practically bubbly. “I can’t imagine a cooler birthday,” she said.發現半人馬座行星的消息正式公布那一天，恰逢她的生日。她在休斯敦的新辦公地接受電話采訪時，聽上去可以說是大喜過望?！拔覠o法想象一個比這更棒的生日了，”她說。
Dr. Jemison’s main work these days is spreading the word and raising money. The prospect of habitable real estate makes the idea of journeying to other stars that much more real, she said, adding: “This is a boon, because most people have heard of Alpha Centauri. It’s close.”這些天來，杰米森的主要工作是傳播消息，籌集資金。她說，在外太空擁有宜居房產的前景使前往其他星球旅行的想法看上去更加真實。她還補充說，“這是一個利好消息，因為大部分人都聽說過半人馬座阿爾法星系。它離地球很近?！?div style="height:15px;">
Well, sort of close. Space is deeper and older than most humans can comprehend. You can’t measure a light-year by your stride. There are 4.4 of them — 27 trillion miles — from here to Alpha Centauri B.算是比較近吧。宇宙比大多數人所能理解的更加深邃，更加古老。你無法用你的步子丈量光年。從地球到半人馬座阿爾法B星的距離是4.4光年，也就是27萬億英里（約合43萬億公里）。
We won’t get there by doing business as usual. Voyager 1, the fastest and most distant human artifact, is more than 11 billion miles from the Sun and is speeding away at 11 miles per second; it would take 78,000 years to get to Alpha Centauri if it were going that way, which it is not.我們無法以尋常的旅行方式抵達那里。人類制造的速度最快、飛離地球最遠的探測器，旅行者1號(Voyager 1)目前已經距離太陽系110萬英里（約合177萬英里），而且還在繼續以每秒11英里（約合17.7公里）的速度飛離太陽系。如果它朝半人馬座阿爾法星系進發，那么它需要花上7.8萬年才能抵達。不過，它并沒有往那個方向飛。
Other schemes, based on existing or about-to-be-existing technology like solar sails and thermonuclear rockets, have been proposed that could reach a tenth the speed of light and make the crossing in less than a human lifetime. (If you have a design for a faster-than-light warp drive, send it directly to Dr. Jemison, not me.)也有人提出了以現有技術或者即將變為現實的技術，像太陽帆、熱核火箭等，為基礎的方案。按照這些方案，星際航行的速度將達到光速的十分之一，人可以在有生之年完成旅行。（如果你設計出了比光速還快的曲速引擎，請直接寄給杰米森，不用給我。）
Of course the cost would be staggering, even for the robots (perhaps genetically engineered nanoprobes) that would precede humans. And whoever eventually goes won’t ever come back.當然，就是對先于人類出發的機器人（可能是通過基因工程建造的納米探測器）來說，旅行的成本也會十分昂貴。而且，不管最后誰去，都不可能回來了。
It won’t be me, despite what I once wrote in my high school yearbook: “Ambition: To go to the stars.”我肯定不去，雖然我曾在中學的學年紀念冊中寫到：“夢想：去外星球。”
Perhaps it is a sign of my age that I think more these days about what I would be leaving behind than what I would be gaining: my family and other loved ones, autumn in the Catskills, one more cowboy trout stream or
New Year’s Eve with old friends.或許，這說明我已不再年輕?，F在，我會更關心的不是自己能得到什么，而是我會失去什么：我的家人和其他我愛的人、卡茨基爾山的秋天、再玩一次飛繩釣的機會，或者和老友一起度過的新年之夜。
I asked Dr. Jemison if she would go, knowing it was forever.我問杰米森，假如知道一去就永遠回不來，還會去嗎？
“Yeah,” she answered. “I would go.”“當然，”她回答道，“我會去?！?div style="height:15px;">
Perhaps hearing the catch of loneliness in my voice, she added, “It makes a difference who goes with you.”或許是聽出了我語氣中暗示的孤獨，杰米森補充道，“當然，誰和你去很重要?！?div style="height:15px;">
