How the First Stars in the Universe Came into Existence The composition of the early universe was quite different from that of today, and the physics that governed the early universe were also somewhat simpler. Dr. Naoki Yoshida and colleagues in Japan and the U. S. incorporated these conditions of the early universe, sometimes referred to as the cosmic dark ages, to simulate the formation Of an astronomical object that would eventually shine its light into this darkness. According to their simulation, gravity acted on minute density variations in matter, gases, and the mysterious dark matter of the universe after the Big Bang in order to form this early stage of a star - a protostar with a mass of just one percent of our sun. The simulation reveals how pre-stellar gases would have actually evolved under the simpler physics of the early universe to form this protostar. Dr. Yoshidas simulation also shows that the protostar would likely evolve into a massive star capable of synthesizing heavy elements, not just in later generations of stars, but soon after the Big Bang. Their simulation of the birth of a protostar in the early universe signifies a key step toward the ambitious goal of piecing together the formation of an entire primordial star and of predicting the mass and properties of these first stars of the universe. More powerful computers, more physical data, and an even larger range will be needed for further calculations and simulations, but these researchers hope to eventually extend this simulation to the point of nuclear reaction initiation when a stellar object becomes a true star. astronomical adj. 天文的;天文学的 pre-stellar adj. 前恒星的 synthesize v.合成,综合 注释: 2. burning question:最吸引人的问题,亟待解决的问题。 4. protostar 原恒星,就是处于原始状态的恒星。原恒星由 大爆炸后产生的星际云演变而来。 练习: A How matter began to form the first stars after the Big Bang. C How the Big Bang took place about 13 billion years ago. 2. What does the astronomical object refer to? C The first star formed in the universe. D Dust grains and gases.
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