天文学家研究新发现的快速形成系外行星
📖 逐句对照翻译
Astronomers have observed a newborn planet that formed in three million years, a relatively brief time.
天文学家观测到一颗新生行星，其形成仅用了三百万年，时间相对短暂。
They say the discovery leads to questions about the current understanding of the speed of planetary formation.
他们说，这一发现使人们对目前关于行星形成速度的认识产生了疑问。
Space scientists estimate the planet to be around 10 to 20 times the mass of Earth.
太空科学家估计这颗行星的质量大约是地球的10到20倍。
It is an exoplanet, meaning a planet outside our solar system.
它是一颗系外行星，意思是太阳系之外的星球。
It is one of the youngest exoplanets ever discovered.
它是迄今发现的最年轻的系外行星之一。
It exists among dense gas and dust orbiting a young star.
它存在于围绕一颗年轻恒星运行的稠密气体和尘埃之中。
The orbiting matter is called a protoplanetary disk.
环绕的物质被称为原行星盘。
It provides the materials necessary for planet formation.
它提供了行星形成所必需的材料。
The star it orbits is not as hot and is about half as bright as our sun.
它环绕的恒星不如我们的太阳热，亮度大约只有太阳的一半。
The star's mass is about 70 percent that of the sun.
这颗恒星的质量约为太阳质量的70%。
It is in our Milky Way galaxy, about 520 light-years from Earth.
它位于我们的银河系中，距离地球约520光年。
A light-year is the distance light travels in a year, 9.5 trillion kilometers.
一光年是光在一年内传播的距离，即9.5万亿公里。
"This discovery confirms that planets can be in a cohesive form within 3 million years, which was previously unclear as Earth took 10 to 20 million years to form," said Madyson Barber, a research student at the University of North Carolina at Chapel Hill (UNC).
北卡罗来纳大学教堂山分校（UNC）的研究学生麦迪逊·巴伯表示：“这一发现证实了行星可以在300万年内以凝聚的形式存在，而此前这一点并不清楚，因为地球花了1000万到2000万年才形成。”
Barber is the lead writer of the study published recently in Nature magazine.
巴伯是近期发表在《自然》杂志上的这项研究的主要作者。
"We don't really know how long it takes for planets to form," UNC professor and study co-writer Andrew Mann added.
北卡罗来纳大学教堂山分校教授、该研究的合著者安德鲁·曼补充道：“我们其实并不清楚行星形成需要多长时间。”
"We know that giant planets must form faster than their disk dissipates because they need a lot of gas from the disk. But disks take 5 to 10 million years to dissipate. So do planets form in one million years? Five? Ten?"
我们知道，巨行星的形成速度必须快于其星盘的消散速度，因为它们需要从星盘中获取大量气体。但星盘需要500万到1000万年才能消散。那么，行星是在100万年内形成的吗？500万年？还是1000万年？
The planet orbits its star every 8.8 days.
这颗行星每8.8天绕其恒星运行一周。
Its mass is in between that of Earth, the largest of our solar system's rocky planets, and Neptune, the smallest of the gas planets.
它的质量介于地球和海王星之间，地球是太阳系岩石行星中最大的，而海王星则是气态行星中最小的。
It is less dense than Earth and has a diameter about 11 times greater.
它的密度比地球小，直径约为地球的11倍。
Its chemical makeup is not known.
它的化学成分尚不清楚。
The researchers suspect that the planet formed further away from its star and then moved closer.
研究人员怀疑这颗行星形成于离其恒星较远的位置，之后才逐渐靠近。
"Forming large planets close to the star is difficult because the protoplanetary disk dissipates away from closest to the star the fastest, meaning there's not enough material to form a large planet that close that quickly," Barber said.
巴伯说：“在靠近恒星的地方形成大型行星很困难，因为原行星盘离恒星越近消散得越快，这意味着没有足够的材料在那么近的地方如此迅速地形成大型行星。”
The researchers found the planet using the so-called "transit" method: observation of a drop in the star's brightness, from the perspective of an observer on Earth, when the planet passes in front of it.
研究人员使用所谓的“凌日”法发现了这颗行星：从地球观测者的视角观察，当行星从恒星前方经过时，恒星的亮度会下降。
NASA's Transiting Exoplanet Survey Satellite, or TESS, space telescope discovered the exoplanet.
美国宇航局的凌日系外行星勘测卫星，简称TESS，太空望远镜发现了这颗系外行星。
"This is the youngest-known transiting planet. It is on par with the youngest planets known," Barber said.
巴伯说：“这是已知最年轻的凌日行星。它与已知最年轻的行星不相上下。”
Stars and planets form from clouds of interstellar gas and dust.
恒星和行星由星际气体和尘埃云形成。
"To form a star-planet system, the cloud of gas and dust will collapse and spin into a flat environment, with the star at the center and the disk surrounding it.
要形成恒星-行星系统，气体和尘埃云将坍缩并旋转成一个扁平的环境，恒星位于中心，盘状物环绕其周围。
Planets will form in that disk.
行星将在那个盘中形成。
The disk will then dissipate” starting from the star side, Barber said.
巴伯说，然后星盘会从恒星一侧开始消散。
"It was previously thought that we wouldn't be able to find a transiting planet this young because the disk would be in the way. But for some reason that we aren't sure of, the outer disk is warped, leaving a perfect window to the star," Barber added.
巴伯补充说：“此前人们认为，我们无法找到如此年轻的凌日行星，因为星体会挡住视线。但出于某种我们尚不确定的原因，外盘发生了翘曲，为观测这颗恒星留下了一扇完美的窗口。”
I'm Caty Weaver.
我是凯蒂·韦弗。
Reuters news agency reported this story.
路透社报道了这则新闻。
Caty Weaver adapted it for VOA Learning English.
凯蒂·韦弗为VOA英语学习频道改编了它。
