It’s common on the beaches of Hawaii to see a crowd of surfers taking advantage of a powerful wave to accelerate themselves to high speed.
在夏威夷的海灘上，看到一群衝浪者利用強大的波浪加速自己高速衝浪是很常見的。
Could extraterrestrial civilizations try to do something similar by “surfing” on the flash of light from an exploding star?
外星文明是否可以通過“衝浪”來自爆炸恆星的閃光來做類似的事情呢？
A light sail weighing less than half a gram per square meter can reach the speed of light even if it’s a hundred times farther away from a supernova than the Earth is from the sun.
重量不到每平方米半克的光帆可以達到光速，即使它距離超新星的距離是地球距離太陽的一百倍。
This is because a typical supernova has a luminosity equivalent to a billion suns shining for a month.
這是因為一顆典型的超新星的亮度相當於十億個太陽一個月的閃耀。
The sun itself is barely capable of accelerating an optimally designed sail to just a thousandth of the speed of light, even if the sail starts its journey as close as 10 times the solar radius—the closest approach of the Parker Solar Probe.
太陽本身幾乎沒有能力將經過優化設計的帆加速到光速的千分之一，即使帆開始其旅程時距離太陽半徑的10倍-這是帕克太陽能探測器最接近的距離。
The terminal speed scales as the square root of the ratio between the star’s luminosity over the initial distance, and can reach a tenth of the speed of light for the most luminous stars.
終端速度是恆星在初始距離上的發光度之比的平方根，對於最明亮的恆星，其速度可以達到光速的十分之一。
Powerful lasers can push light sails much better than the sun.
強大的激光可以比太陽更好地推動光帆。
The Breakthrough Starshot project aims to reach several tenths of the speed of light by pushing a lightweight sail for a few minutes with a laser beam that can achieve 10 gigawatts per square meter—10 million times brighter than sunlight on Earth.
Breakthrough Starshot項目的目標是通過將一個輕量級的帆推幾分鐘來達到十分之幾的光速，激光束的功率可以達到每平方米10千兆瓦-比地球上的陽光亮度高出1000萬倍。
But to reach this goal requires a major investment in the infrastructure needed to produce and collimate such a light beam.
但要達到這一目標，需要在生產和準直這種光束所需的基礎設施上進行重大投資。
Alternatively, a civilization that happens to reside near a massive star such as Betelgeuse or Eta Carinae could park numerous light sails around it, awaiting the powerful explosion that would launch these sails to the speed of light at a minimal cost.
或者，碰巧居住在像參宿四或船底座這樣的大質量恆星附近的文明可以在它周圍放置大量的光帆，等待強大的爆炸以最小的代價將這些帆以光速發射出去。
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