| Bottom | Home | Article | Bookshelf | Keyword | Author | Oxymoron |


The Three Suns of Centaurus

Cat: SCI
Pub: 1982

Paul Patton



The Three Suns of Centaurus


Paul Patton ポール・パットン

Jan. 1982

  1. Prologue:
  2. Alpha Centauri system (Triple):
  3. The Daedalus Starship:
  4. Human-borne spaceship:
  1. プロローグ:
  2. ケンタウルス座α星系 (三重星):
  3. ダイダロス恒星間宇宙船:
  4. 人類を乗せた宇宙船:
  • This is compiled from a cover story of "Exploring The Suns of Centaurus", Astronomy, Jan. 1982.
  • Alpha Centauri is a special star for us, not only because it is the closest to us but also it may harbor intelligent life. It is visible from latitude south of 25 degrees. It is also a triple star system.
  • None greater than that of Alpha Centauri has ever been found: 0.75 second of arc, corresponds to 40 trillion km from Earth, or 270,000AU, or 4.3 light-years distant.
  • If a starprobe were launched for survey of Alpha Centauri system, it would take about 38 years at more than a tenth speed of light.
  • これはAstronomy誌(1982年1月号) の「ケンタウルス座の太陽たちの探査」の記事からである。
  • ケンタウルス座α星は我々にとって特別な星である。それは我々に近いだけでなく知的生命を宿しているかも知れないからである。それは南緯25度から見られる。
  • ケンタウルス座α星は視差が最も大きく、0.75秒度あり、地球からの距離は40兆kmで、これは270,000AU 、4.3光年の遠方に相当する。
  • もし恒星探査船がケンタウルス座α星系の探査に打ち上げられたとすると、到着するには光速度の10%以上の速度でも約38年もかかる。
αCen A
αCen B
αCen C
Spectral type
Surface temp(K)
Distance (ly)
Age (B-yr)
5 -6
5 - 6

centaurus >Top 0. Prologue:

  • Greek legend:
    According to ancient Greek legend, strange creatures with the sleek powerful body of a horse and the trunk, arms, and head of a man once roamed northern Greece; they were called centaurs. One of them, Chiron, was wise and just. He distinguished himself as a teacher of many famous Greek heroes, including the warrior Achilles. When Chiron died, Zeus, the ruler of the gods, honored him by placing him among the stars.
  • centauri_trippleConstellation Centaurus:
    Thus, today's charted constellations retain the names of mythological Greek heroes and monsters. If you look to the south of Virgo and Hydra, you'll see the constellation Centaurus, named for the honored Chiron.
  • Triple system:
    Of all the stars, none is closer to our Sun than the triple star system we have named Alpha Centauri. In our exploration of the stars, these three suns of Centaurus will undoubtedly be our first port of call. For the present, we can only peer at Alpha Centauri across an immense void of empty space.
  • Binary system:
    Alpha Centauri is really two stars; Centauri A (magnitude 0.0) and B (magnitude 1.3). They revolve around each other under mutual gravitational influence, and complete one cycle every 80 terrestrial years. Their orbits are highly elliptical, so the distance between them varies greatly over the course of one centaurian year.
  • Periastron:
    At the point of closest approach, periastron, the two stars are separated by about 11 AU, and at the point of farthest separation, apastron, they are about 35 AU apart. The average separation is 23 AU - about the distance from the Sun to Uranus. (1AU = 150 million km)
  • Proxima:
    If we observe carefully, we note an 11th magnitude star (Alpha Centauri C) not far from Alpha Centauri A and B pair. At the present point in its orbit, this small unimpressive star - sometimes called Proxima - is actually the nearest star to our Sun. (4.22 light years) It orbits more than 10,000 AU from the A and B pair.
  • Planets of Alpha Centauri system:
    As many as four families of planets could revolve within the Alpha Centauri system:
    • One family circles Alpha Centauri A
    • Another orbits Alpha Centauri B
    • A third revolves around the A-B pair.
    • A fourth family orbits Alpha Centauri C.

0. プロローグ:

  • ギリシャ神話
    ギリシャ神話 によれは、均整のとれた馬の身体、鼻、腕と、人間の頭をもつ奇妙な怪物がギリシャ北方を放浪していた。それらはケンタルウスと呼ばれていた。その内の一頭はケイローンと呼ばれ、賢く高潔であった。彼はアキレスのような多くのギリシャの英雄たちの教師であった。ケイローンが死んだとき、最高神ゼウスは、彼を崇め星々の間に安置した。
  • ケンタウルス座
  • 三重星
  • 連星
    ケンタウルス座α星は、実際にはA星 (0等星) とB星 (1.3等星の) 連星である。それらは互いに重力の影響を受けて相互に回転している。公転周期は80年で、その軌道は扁平な楕円で、公転の間に相互の距離は大きく変化する。
  • 近星点
    2つの星が最も近づく近星点では、11AU (天文単位) で、遠星点では35AUである。平均は23AUで、これはほぼ太陽と天王星の距離である。 (1AU = 1.5億km)
  • プロキシマ
    注意深く観測すると、11等星のケンタウルス座α星Cが、A星とB星の近くに見つかる。現在の軌道の位置では、この目立たない星は4.22光年離れておりで、太陽から一番近いので Proxima と呼ばれる。その軌道はA星とB星の連星から10,000AU以上も離れている。
  • ケンタウルス座α星の惑星
    • ケンタウルス座α星Aを周回する惑星
    • ケンタウルス座α星Bを周回する惑星
    • ケンタウルス座α星AとBの連星を周回する惑星
    • ケンタウルス座α星Cを周回する惑星

>Top 1. Alpha Centauri system (Triple):

  • Alpha Centauri A:
    Of the 50 stars within 16 light-years of our solar system, Alpha Centauri A is most similar to our Sun. Its mass ia about 1.08 times that of the Sun and its radius is approximately the same. Intrinsically, it is about 1.3 times as bright as the Sun. Both stars are classified as member of spectral class G2; stars that shine brightest in yellow, and have a surface temperature of about 5800 K. Absolute magnitude is -0.04.
  • Alpha Centauri B:
    It is somewhat smaller and fainter that the Sun. Its mass is 0.88, and its radius about 0.74 times the Sun's - it is only half as bright intrinsically. It is a spectral class K1 star, and is brightest in the orange region. Its surface temperature is about 5300 K. absolute magnitude is 1.33.
  • Alpha Centauri C:
    It has a mass only 0.12 times that of the Sun or about 100 times that of Jupiter; its radius measures about a third the Sun's, and it is 1/10000 as bright. It is a spectral class M5 star. It emits much of its light in the red and infrared portions of the spectrum and has a surface temperature about 2700 K. Absolute magnitude is 11.05.

1. ケンタウルス座α星系 (三重星) :

  • ケンタウルス座α星A
    太陽系から16光年以内の50個の星の中で、ケンタウルス座α星Aは太陽と最もよく似ている。その質量は太陽の約1.08倍で、半径はほぼ同じ。光度は太陽の1.3倍である。この星も太陽もスペルトルではG2であり、黄色で最も明るい。表面温度は約5800度K。見かけ等級は -0.04等星である。
  • ケンタウルス座α星B
  • ケンタウルス座α星C

>Top 2. The Daedalus Starship:

  • Daedalus:
    daedalus_ikarusmythical Greek architect and sculptor, who was said to have built,the paradigmatic Labyrinth for King Minos of Crete. Daedalus fell out of favor with Minos and was imprisoned; he fashioned wings of wax and feathers for himself and for his son Icarus and escaped to Sicily. Icarus, however, flew too near the Sun, and his wings melted; he fell into the sea and drowned. The island on which his body was washed ashore was later named Icaria. (Source: Britannica 2003)
  • Project daedalus (1973-77):
    The British Interplanetary Society attempted to develop a preliminary design for an interstellar probe called Project Daedalus. It would perform the daedalussimplest possible mission, a flyby. It would be triggered by high powered electron beams bombarding nuclear fuel pellets. The engine would fire continuously for 4 years, burning 50,000 tons of fuel and accelerating to about 36,000 km/s - 12% the velocity of light.
    • Flight time: 38 years
    • Top speed: 12% light speed
    • Boost period: 4 years
    • Engine: nuclear pulse rocket
    • Propellants: deuterium, helium
    • Payload mass: 500 tons
  • 32 years after launch:
    The starship would approach Alpha Centauri. Having scanned the system already and selected its targets, it would deploy a number of instrument probes to closely examine various planets. The findings, radioed back after on-board analysis, would reach Earth more than 4 years later.We will need to develop semi-intelligent computers capable of reprogramming themselves and making complex decisions independently.
  • Advanced robot ships:
    Eventually, if we develop still more advanced propulsion systems, or are willing to accept longer transit times, we may send robot ships that can decelerate and explore the Alpha Centauri system in detail from orbits around the stars. These advanced probes might even deploy landers and roving vehicles onto the planets of the system.
  • Intelligent Centaurians:
    Perhaps, on some planet within the ecosphere of one of the three suns, they would find life. Imagine the surprise - or consternation - of intelligent centaurians if a strange machine of metal and glass rolled into their community with its cameras whirring! (Image our surprise if the reverse were true!)

2. ダイダロス恒星間宇宙船:

  • ダイダロス:
    ギリシャ神話では はクレタ島のミノス王のために絶好の迷宮を作った建築家・彫刻家である。ダイダロスはミノス王の支持を失い投獄される。彼は自分と息子のためにワックスと羽毛で羽根を作り、シシリーへ脱出する。しかしイカルスはあまりにも太陽の近くを飛んだので彼の羽根は説けてしまい、海に落ちて溺れてしまった。彼の体が波に打ち上げられた島は後にイカリアと呼ばれた。 (出典:Britannica 2003)
  • ダイダロス計画 (1972-77):
    • 航行時間:38年
    • 最高速度:光速の12%
    • 加速期間:4年
    • エンジン:核燃料パルス・ロケット
    • 推進燃料:重水素、ヘリウム
    • 荷重量:500トン
  • 打ち上げ32年後
  • 先進的なロボット宇宙船
  • 知的なケンタウルス座α星人

>Top 3. Human-borne spaceship:

  • Sending humans to explore the Alpha Centauri system would be vastly more difficult than sending intelligent machines. Humans would require food, water, oxygen, companionship, and a stimulating environment over the long voyage. There could be several options:
    1. Very fast but small spacecraft:
      A spacecraft that accelerated at 1g for half the trip and decelerated at 1g for the other half could reach Alpha Centauri with an elapsed ship-time of less than 5 years. The astronauts aboard would feel one normal Earth gravity for the entire trip. Such a starship would require titanic quantities of energy.
    2. Large but slow spacecraft:
      Thousands of people, plants, and animals could live for many generations in a closed ecosystem. Creating and maintaining such an ecosystem, however, would be very difficult.
    3. State of hibernation:
      A third option is to place the crew in a state of prolonged hibernation or suspended animation. Then we could send crews on voyages lasting many decades with a minimum of provisioning and living space. Humans might then travel to Alpha Centauri without a very advanced propulsion system or closed ecosystem. Unfortunately, no one knows how the required state of hibernation might be achieved.
  • The night sky remains for us:
    The full exploration of the Alpha Centauri system awaits breakthroughs in engineering, ecology, physiology, or cryobiology. In the meantime, the three suns of Centaurus beckon to us across the light-years. The shining point in the front hoof of the Centaur, visible on a clear night in the southern skies, draws our minds outward. The night sky remains for us what is was for the ancient Greeks - an invitation to imagine unknown worlds and exotic creatures.

3. 人類を乗せた宇宙船:

  • 人間をケンタウルス座α星系探査に送り出すことは知的な機械を送り出すよりもはるかに困難である。人間は食料、水、酸素、仲間、長期間の旅行が可能な刺激的な環境が必要となる。このためにいくつかの選択肢がある。
    1. 高速・小型宇宙船
    2. 巨大・遅い宇宙船
    3. 冬眠状態
  • 夜空は依然のまま...:
  • Thou shalt love thy neighbor as thyself. (Matt. 19:19)
  • When we recognize Alpha Centauri is our neighbor, we can expand our global world to cosmic community.
  • 己を愛するように汝の隣人を愛せよ (マタイ伝)
  • 我々がケンタウルス座α星を我々の隣人として認めるとき、我々はグローバルな世界を宇宙的コミュニティに広げることができるだろう。

| Top | Home | Article | Bookshelf | Keyword | Author | Oxymoron |