我們發現了一個新地球，而且不太遠

Astronomers have found a  nearby "super-Earth" exoplanet that may be capable of supporting life as we know it.

天文學家發現附近有一顆“超級地球”外星球，據我們所知可能有生命存在。

An international group of astronomers discovered the planet using NASA's Transiting Exoplanet Survey Satellite (TESS) earlier this year in the constellation Hydra, about 31 light-years from Earth, according to a statement by NASA.

NASA的一份聲明稱，今年早些時候一個國際天文學家團隊利用NASA的凌日系外行星勘測衛星（TESS）在長蛇座發現了這顆星球，距離地球約31光年。

(One light-year is the distance light travels in a year, about 6 trillion miles, or 10 trillion kilometers.)

（1光年就是光傳播一年所經過的距離，約6萬億英里，或10萬億千米。）

The exoplanet, named GJ 357 d, is believed to be around twice the size of Earth and harbor six times Earth's mass.

這顆稱爲GJ 357 d的外星球據認爲大約有地球兩倍大，質量爲地球的六倍。

Located in the outer edge of its host star's "habitable zone," scientists believe that this super-Earth could have water on its surface.

這顆超級地球位於其主恆星“宜居帶”的外緣，科學家認爲它表面上會有水。

"If the planet has a dense atmosphere, which will take future studies to determine, it could trap enough heat to warm the planet and allow liquid water on its surface," Diana Kossakowski, a researcher at the Max Planck Institute for Astronomy in Heidelberg, Germany, and co-author of the recent study, said in the statement.

德國海德堡的馬克斯-普朗克天文研究所的研究員Diana Kossakowski是最近這項研究的共同作者，在聲明中說：“這顆行星是否有稠密的大氣層還有待未來研究進行考證，如果有，就可以吸收足夠的熱量來加熱這顆行星，其表面上就會存在液態水。”

The potentially habitable planet and two neighboring worlds were found orbiting around a dwarf star, around a third the size and mass of our own sun and 40% cooler.

已發現這顆潛在的宜居星球和兩顆臨近的行星圍繞一顆白矮星運行，這顆白矮星體積和質量約爲太陽的三分之一，溫度比太陽低40%。

TESS noticed that the light coming from this small star dims slightly every 3.9 days — a clue that an exoplanet may be transiting its face.

凌日系外行星勘測衛星注意到這顆小恆星發出的光每3.9天會暗淡一次，說明有一顆外星球可能正經過其表面。

That world is GJ 357 b, a "hot Earth" that orbits 11 times closer to its host star than Mercury does to the sun and likely has a surface temperature of around 490 degrees Fahrenheit (254 degrees Celsius).

這顆星球是GJ 357 b，被稱爲“熱地球”，距離其主恆星的距離比水星與太陽的距離近11倍，表面溫度可能約爲490華氏度（254攝氏度）。

But GJ 357 b's possibly habitable neighbor planet soon stole the show.

但GJ 357 b旁邊可能適宜居住的星球很快就搶佔了風頭。

Further observations showed that GJ 357 d orbits its star every 55.7 days at a distance of around a fifth of Earth's distance from the sun, and could have Earth-like conditions, according to a statement from Cornell University.

康奈爾大學的一份聲明稱，進一步的觀察顯示GJ 357 d圍繞恆星的運行週期爲55.7天，距離其主恆星的距離約爲日地距離的五分之一，條件與地球相似。

翻譯：菲菲