There, hydrogen -the lightest of all elements -experienced extraordinary amounts of compression, owing to the density of the clouded gases around it, and underwent nuclear fusion, or the bonding of atomic nuclei. The center of the cloud, where the greatest amount of gases gathered, was naturally the densest and most massive portion as well as the hottest. Somewhere between the center and the rim of the Milky Way, a rotating cloud of cosmic gas formed about six billion years ago, Scientists today believe that the universe began between 10 and 20 billion years ago, with an event nicknamed the "big bang," The galaxies continued (and still continue) to move outward from that center, and among them was our Milky Way. HOW IT WORKS Formation of the Sun and Planets Together, these two bodies literally define time in human experience, which has been marked by the movements of the Sun and Moon from a time before civilization began. For all its influence on human life, however, the Sun has less impact on the tides than the Moon, which is smaller but much closer. For that matter, Earth itself would not exist: our planet appears to have developed from the same cosmic cloud that formed the Sun, and without the Sun to hold it in place with its gravitational pull, Earth would go spinning off into space. Without the Sun, of course, life on Earth simply could not exist, not just because of the need for light but to an even greater degree because of the energy it supplies. “Perhaps, with a better understanding of its basic physics, we will be able to build better models to predict space weather in the future, thus allowing the implementation of protection strategies that could head off - literally - billions of dollars of damage.Earth is intimately tied to the star around which it revolves, the Sun, and the satellite that revolves around Earth itself, the Moon. “The solar corona’s dynamics can have profound impacts on Earth,” he said in a statement. The researchers then tested the hypothesis using six-dimensional computer simulations and found the magnetic field structures and coronal gas eddies generated hewed close to observations of the actual solar corona made by Nasa’s Parker Solar Probe spacecraft, which first flew through the Sun’s corona in December.Īnd beyond gaining a better understanding of solar coronal physics for its own sake, said study co-author Dr Romain Meyrand, scientists will better understand and be able to predict space weather events that can affect spacecraft near Earth. Through a phenomenon they call the helicity barrier, they theorize that the low-frequency turbulence process diverts electrons’ energy into the creation of ion-cyclotron waves, which then heat the ions. But they don’t fit observations that ions - the cores of hydrogen, helium and oxygen atoms stripped of their electrons - become superheated while electrons remain relatively cool in the corona.Ī hypothesis involving a sort of magnetic wave known as high-frequency ion-cyclotron waves can explain the differential heating between ions and electrons, but scientists haven’t found a clear source for such waves.īut in the new paper, Dr Squire and his colleagues argue that both turbulent and magnetic waves are two components of a larger, unified process of coronal heating. Hypotheses involving a form of turbulence known as low-frequency “Alfvénic” turbulence are supported by observations by spacecraft and would explain the transportation of energy outwards from the Sun. “Astrophysicists have several different ideas about how the magnetic-field energy could be converted into heat to explain the heating, but most have difficulty explaining some aspect of observations.” “We know from measurements and theory that the sudden temperature jump is related to magnetic fields which thread out of the Sun’s surface,” the lead author of the study, Jonathan Squire, said in a statement. Temperatures in the corona regularly measure more than 1 million degrees Celsius, and scientists believe that the process that generates this intense heat so far from the Sun’s core may govern how powerfully the solar wind flows from the Sun. The Sun’s surface is relatively temperate compared with the Sun’s upper atmosphere, or corona, the wispy tendrils of plasma seen around the edge of the Moon during a total eclipse and ranging from a few hundred kilometers to five million kilometers above the surface. As the outer edge of a massive ball of gas superheated by thermonuclear reactions fusing hydrogen atoms into helium atoms, the surface of the Sun is extremely hot – a blistering 6,000 degrees Celsius.
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