* Astronomy

Blobrana · L

RE: Asteroseismology

Blobrana · L

Stars may be many light-years away but the sounds they produce can give scientists insights into their size, age and whether habitable Earth-like planets are nearby.
The study of star sounds, called asteroseismology, helps scientists working with the Kepler Space Telescope in their hunt for life in the depths of the Universe.
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Blobrana · L

Kepler's surprise: The sounds of the stars

Data from NASA's Kepler space telescope have revolutionized the search for planets outside the Solar System - and are now doing the same for asteroseismology.
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Blobrana · L

Title: Asteroseismology of red giants as a tool for studying stellar populations: first steps
Authors: Andrea Miglio

The detection of solar-like oscillations in G and K giants with the CoRoT and Kepler space-based satellites allows robust constraints to be set on the mass and radius of such stars. The availability of these constraints for thousands of giants sampling different regions of the Galaxy promises to enrich our understanding on the Milky Way's constituents. In this contribution we briefly recall which are the relevant constraints that red-giant seismology can currently provide to the study of stellar populations. We then present, for a few nearby stars, the comparison between radius and mass determined using seismic scaling relations and those obtained by other methods.

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Blobrana · L

Structure of stars revealed by 'music' they emit

The sounds emitted by stars light years away from Earth have been captured by British astronomers using Nasa's Kepler space telescope.
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Blobrana · L

Astrophysicists probing the heart of a star

Two teachers from the Department of physics, Gilles Fontaine and Pierre Brassard and a third from the University of Toulouse and graduate of the UdeM Stéphane Charpinet made a world first measurement of a stars core rotational speed. So far, such information was known only for our own Sun. The work of the team was published in the September 24 nature issue.

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Blobrana · L

Title: The Current Status of Asteroseismology
Authors: C. Aerts, J. Christensen-Dalsgaard, M. Cunha, D.W.Kurtz

Stellar evolution, a fundamental bedrock of modern astrophysics, is driven by the physical processes in stellar interiors. While we understand these processes in general terms, we lack some important ingredients. Seemingly small uncertainties in the input physics of the models, e.g., the opacities or the amount of mixing and of interior rotation, have large consequences for the evolution of stars. The goal of asteroseismology is to improve the description of the interior physics of stars by means of their oscillations, just as global helioseismology led to a huge step forward in our knowledge about the internal structure of the Sun. In this paper we present the current status of asteroseismology by considering case studies of stars with a variety of masses and evolutionary stages. In particular, we outline how the confrontation between the observed oscillation frequencies and those predicted by the models allows us to pinpoint limitations of the input physics of current models and improve them to a level that cannot be reached with any other current method.

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