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How the First Stars in the Universe Came into Existence How the first stars formed from this dust and gas has been a burning question for years, but a state-of-the- art computer simulation now offers the most detailed picture yet of how these first stars in the universe came into existence, researchers say. 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. The result is a detailed description of the formation of a protostar-the early stage of a massive primordial star of our universe, and the researchers’ computer simulation, which has been called a "cosmic Rosetta Stone." sets the bar for further investigation into the star formation process. The question of how the first stars evolved is so important because their formations and eventual explosions provided the seeds for subsequent stars to come into being. 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. Yoshida’s 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. "This geneal picture of star formation, and the ability to compare how stellar objects form in different time periods and regions of the universe, will eventually allow investigation into the originsof life and planets, " said Lars Hernquist, a Professor of Astronomy at Harvard University and a coauthor of this latest report. "The abundance of elements in the universe has increased as stars have accumulated, " he says, "and the formation and destruction of stars continues to spread these elements further across the universe. So when you think about it, all of the elements in our bodies originally formed from nuclear reactions in the centers of stars, long ago." 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. "Dr. Yoshida has taken the study of primordial star formation to a new level with this simulation, but it still gets us only to the halfway point towards our final goal. It is like laying the foundation of a skyscraper, " said Volker Bromm, Assistant Professor of Astronomy at the University of Texas, Austin and the author of a companion article. "We must continue our studies in this area to understand how the initially tiny protostar grows, layer by layer, to eventually form a massive star. Buthere, the physics become much more complicated and even more computational resources are needed." What does the state-of-the art computer simulation tell us about
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Europa’s Watery under World Europa, one of Jupiter’s 63 known moons, looks bright and icy on the surface. But appearances can be deceiving: Miles within its cracked, frigid shell, Europa probably hides giant pools of liquid water. Where scientists find liquid water, they hope to find life as well. Since we can’t go diving into Europa’s depths just yet, scientists instead have to investigate the moon’s surface for clues to what lies beneath. In a new study, scientists investigated one group of strange ice patterns on Europa and concluded that the formations mark the top of an underground pool that holds as much water as the U. S. Great Lakes. Pictures of Europa, which is slightly smaller than Earth’s moon, clearly show a tangled, icy mishmash of lines and cracks known as "chaos terrains." These chaotic places cover more than half of Europa. For more than 10 years, scientists have wondered what causes the formations. The new study suggests that they arise from the mixing of vast underground stores of liquid water with icy material near the surface. For scientists who suspect that Europa also may be hiding life beneath its icy surface, the news about the new lake is exciting. "It would be great if these lakes harbored life, " Britney Schmidt, a planetary scientist who worked on the study, told Science News. "But even if they didn’t, they say that Europa is doing something interesting and active right now. " Schmidt, a scientist at the University of Texas at Austin, and her colleagues wanted to know how chaos terrains form. Since they couldn’t rocket to Europa to see for themselves, they searched for similar formations here on Earth. They studied collapsed ice shelves in Antarctica and icy caps on volcanoes in Iceland. Those features on Earth formed when liquid water mixed with ice. The scientists now suspect something similar might be happening on Europa: that as water and ice of different temperatures mingle and shift, the surface fractures. This would explain the jumbled ice sculptures. "Fracturing catastrophically disrupts the ice in the same way that it causes ice shelves to collapse on Earth, " Schmidt told Science News. She and her team found that the process could be causing chaos terrains to form quickly on Europa. The new study suggests that on this moon, elements such as oxygen from the surface blend with the deep bodies of water. That mixture may create an environment that supports life. The size of Europa is a bit larger than that of Earth’s moon.
Students Learn Better with Touchscreen Desks Observe the criticisms of nearly any major public education system in the world, and a few of the many complaints are more or less universal. Technology moves faster than the education system. Teachers must teach at the pace of the slowest student rather than the fastest. And—particularly in the United States—grade school children as a group don’t care much for, or excel at, mathematics. So it’s heartening to learn that a new kind of "classroom of the future" shows promise at mitigating some of these problems, starting with that fundamental piece of classroom furniture: the desk. AUK study involving roughly 400 students, mostly aged 8-10 years, and a new generation of multi- touch, multi-user, computerized desktop surfaces is showing that over the last three years the technology has appreciably boosted students’ math skills compared to peers learning the same material via the conventional paper-and-pencil method. How Through collaboration, mostly, as well as by giving teachers better tools by which to micromanage individual students who need some extra instruction while allowing the rest of the class to continue moving forward. Science, Clay Dillow, classroom of the future, education, engineering, math, mathematics, Synergy Net Traditional instruction still shows respectable efficacy at increasing students fluency in mathematics, essentially through memorization and practice—dull, repetitive practice. But the researchers have concluded that these new touch screen desks boost both fluency and flexibility—the critical thinking skills that allow students to solve complex problems not simply through knowing formulas and devices, but by being able to figure out what there all problem is and the most effective means of stripping it down and solving it. One reason for this, the researchers say, is the multi-touch aspect of the technology. Students working in the next-gen classroom can work together at the same tabletop, each of them contributing and engaging with the problem as part of a group. Known as Synergy Net, the software uses computer vision systems that see in the infrared spectrum to distinguish between different touches on different parts of the surface, allowing students to access and use tools on the screen, move objects and visual aids around on their desktops, and otherwise physically interact with the numbers and information on their screens. By using these screens collaboratively, the researchers say, the students are to some extent teaching themselves as those with a stronger grasp on difficult concepts pull other students forward along with them. Which of the following statements is NOT true of the public education system
Europa’s Watery under World Europa, one of Jupiter’s 63 known moons, looks bright and icy on the surface. But appearances can be deceiving: Miles within its cracked, frigid shell, Europa probably hides giant pools of liquid water. Where scientists find liquid water, they hope to find life as well. Since we can’t go diving into Europa’s depths just yet, scientists instead have to investigate the moon’s surface for clues to what lies beneath. In a new study, scientists investigated one group of strange ice patterns on Europa and concluded that the formations mark the top of an underground pool that holds as much water as the U. S. Great Lakes. Pictures of Europa, which is slightly smaller than Earth’s moon, clearly show a tangled, icy mishmash of lines and cracks known as "chaos terrains." These chaotic places cover more than half of Europa. For more than 10 years, scientists have wondered what causes the formations. The new study suggests that they arise from the mixing of vast underground stores of liquid water with icy material near the surface. For scientists who suspect that Europa also may be hiding life beneath its icy surface, the news about the new lake is exciting. "It would be great if these lakes harbored life, " Britney Schmidt, a planetary scientist who worked on the study, told Science News. "But even if they didn’t, they say that Europa is doing something interesting and active right now. " Schmidt, a scientist at the University of Texas at Austin, and her colleagues wanted to know how chaos terrains form. Since they couldn’t rocket to Europa to see for themselves, they searched for similar formations here on Earth. They studied collapsed ice shelves in Antarctica and icy caps on volcanoes in Iceland. Those features on Earth formed when liquid water mixed with ice. The scientists now suspect something similar might be happening on Europa: that as water and ice of different temperatures mingle and shift, the surface fractures. This would explain the jumbled ice sculptures. "Fracturing catastrophically disrupts the ice in the same way that it causes ice shelves to collapse on Earth, " Schmidt told Science News. She and her team found that the process could be causing chaos terrains to form quickly on Europa. The new study suggests that on this moon, elements such as oxygen from the surface blend with the deep bodies of water. That mixture may create an environment that supports life. The liquid water of an underground pool of Europa is estimated to be equivalent to the water of the U. S. Great lakes.
How the First Stars in the Universe Came into Existence How the first stars formed from this dust and gas has been a burning question for years, but a state-of-the- art computer simulation now offers the most detailed picture yet of how these first stars in the universe came into existence, researchers say. 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. The result is a detailed description of the formation of a protostar-the early stage of a massive primordial star of our universe, and the researchers’ computer simulation, which has been called a "cosmic Rosetta Stone." sets the bar for further investigation into the star formation process. The question of how the first stars evolved is so important because their formations and eventual explosions provided the seeds for subsequent stars to come into being. 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. Yoshida’s 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. "This geneal picture of star formation, and the ability to compare how stellar objects form in different time periods and regions of the universe, will eventually allow investigation into the originsof life and planets, " said Lars Hernquist, a Professor of Astronomy at Harvard University and a coauthor of this latest report. "The abundance of elements in the universe has increased as stars have accumulated, " he says, "and the formation and destruction of stars continues to spread these elements further across the universe. So when you think about it, all of the elements in our bodies originally formed from nuclear reactions in the centers of stars, long ago." 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. "Dr. Yoshida has taken the study of primordial star formation to a new level with this simulation, but it still gets us only to the halfway point towards our final goal. It is like laying the foundation of a skyscraper, " said Volker Bromm, Assistant Professor of Astronomy at the University of Texas, Austin and the author of a companion article. "We must continue our studies in this area to understand how the initially tiny protostar grows, layer by layer, to eventually form a massive star. Buthere, the physics become much more complicated and even more computational resources are needed." According to the first two paragraphs, the early universe ______.
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