Astronomers2 using the National Science Foundations Green Bank Telescope -- among other telescopes -- have determined3 that our own Milky4 Way galaxy5 is part of a newly identified ginormous supercluster of galaxies6, which they have dubbed7 Laniakea, which means immense heaven in Hawaiian. This discovery clarifies the boundaries of our galactic neighborhood and establishes previously8 unrecognized linkages9 among various galaxy clusters in the local Universe.We have finally established the contours that define the supercluster of galaxies we can call home, said lead researcher R. Brent Tully, an astronomer1 at the University of Hawaii at Manoa. This is not unlike finding out for the first time that your hometown is actually part of much larger country that borders other nations.The paper explaining this work is the cover story of the September 4 issue of the journal Nature.Superclusters are among the largest structures in the known Universe. They are made up of groups, like our own Local Group, that contain dozens of galaxies, and massive clusters that contain hundreds of galaxies, all interconnected in a web of filaments10. Though these structures are interconnected, they have poorly defined boundaries.To better refine cosplaymic mapmaking, the researchers are proposing a new way to evaluate these large-scale galaxy structures by examining their impact on the motions of galaxies. A galaxy between structures will be caught in a gravitational tug-of-war in which the balance of the gravitational forces from the surrounding large-scale structures determines the galaxys motion.By using the GBT and other radio telescopes to map the velocities11 of galaxies throughout our local Universe, the team was able to define the region of space where each supercluster dominates. Green Bank Telescope observations have played a significant role in the research leading to this new understanding of the limits and relationships among a number of superclusters, said Tully.The Milky Way resides in the outskirts12 of one such supercluster, whose extent has for the first time been carefully mapped using these new techniques. This so-called Laniakea Supercluster is 500 million light-years in diameter and contains the mass of one hundred million billion Suns spread across 100,000 galaxies.This study also clarifies the role of the Great Attractor, a gravitational focal point in intergalactic space that influences the motion of our Local Group of galaxies and other galaxy clusters.Within the boundaries of the Laniakea Supercluster, galaxy motions are directed inward, in the same way that water streams follow descending13 paths toward a valley. The Great Attractor region is a large flat bottom gravitational valley with a sphere of attraction that extends across the Laniakea Supercluster.The name Laniakea was suggested by Nawaa Napoleon, an associate professor of Hawaiian Language and chair of the Department of Languages, Linguistics14, and Literature at Kapiolani Community College, a part of the University of Hawaii system. The name honors Polynesian navigators who used knowledge of the heavens to voyage across the immensity of the Pacific Ocean.
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1 astronomer n.天文学家 参考例句： A new star attracted the notice of the astronomer.新发现的一颗星引起了那位天文学家的注意。 He is reputed to have been a good astronomer.他以一个出色的天文学者闻名于世。
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