美國加州大學圣克魯茲分校的一位天體物理學教授利用自創的公式計算出了宇宙中不同天體的價值，其中地球價值為3千萬億英鎊，是最貴的一個，火星的價值只有1萬英鎊，而金星則一文不值。這位教授的計算公式中結合了天體的年代、大小、溫度、質量以及其它一些重要的數據，天體的年代越久遠，價值就會隨之增加。另外，能否產生能源以及溫度是否適合生命存活也是計算天體價值的重要因素。這位教授表示，宇宙中還有大約1235個已知的行星，大多數都因為無法居住而價值不高，只有那些估值在6000萬英鎊以上的行星才值得研究。

A scientist has created a formula to calculate the worth of planet Earth and has valued it at three thousand trillion pounds.

A scientist has created a formula to calculate the worth of planet Earth and has valued it at three thousand trillion pounds.

Astrophysicist Greg Laughlin came up with the figure by calculating the sum of the planet’s age, size, temperature, mass and other vital statistics – and Earth came out as the most expensive.

Mars was only valued at ￡10,000, while Venus is said to be worth less than a penny.

There are about 1,235 other planets in the universe, most of which weren’t given a high price tag because of their inhospitable climates.

Professor Laughlin from the University of California-Santa Cruz invented the equation, which he used to evaluate the discoveries made by Nasa’s ￡600 million Kepler spacecraft .

The planet-hunting spacecraft went into orbit two years ago and a year later Laughlin decided to create price tags for the terrestrial planets that Keplar was set to discover.

At the time, the exoplanet Gilese 581 c was considered the most Earth-like world known to scientists, but the equation only valued it at ￡100, while KOI 326.01 is said to be worth ￡150,000.

Laughlin told science writer Lee Billings last week: ‘I’ve just always thought that the concept of an ‘Earth-like planet in the habitable zone’ was pretty vaguely defined, and I wanted a metric that I could plug a planet into to see whether its value was high enough to warrant media hype.

‘This is just a way for me to be able to quantify how excited I should be about any particular planet.’

The older the star, the more value it has because it has had the chance to mature, the mass is then taken into account and generally if it’s around the same size as Earth it is thought of as a good size for supporting life.

Laughlin also took into account the amount of energy the star creates and whether its temperatures could also support life.

The professor concluded that planets with a value of ￡60 million or more are worth studying but the ones worth less aren’t.

He also said: ‘The formula makes you realise just how precious Earth is and I hope it will help us as a society safeguard what we have.

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(Agencies)

（中國日報網英語點津 Helen 編輯）