Astrocast.TV

Posts Tagged ‘computer models’

Astronomers have attempted to comprehend the formation of the solar system for decades. As computers have gotten more and more capable of performing millions of mathematical operations per second, our computer models of this formation process has coalesced like the planetesimals themselves. This past Wednesday, astronomers from the Hawaii Institute of Geophysics and Planetology, released results from their latest attempts to model the formation of our solar system. You can learn more about these computer models, and see animations developed from them, online now here.

In a paper to be published in Astronomy and Astrophysics, available online now here, astronomers report their results of the modeling of planet formation in a system that develops within a cluster of stars, and has a type of gravitational encounter with a neighbor. The authors note that “the majority of stars in the Galaxy are thought to have formed within stellar clusters.” So they exercised a series of computer models where they “consider the effect on both the mass accretion and the migration history as a function of encounter distance.” They conclude that “planets that undergo such encounters are expected to be more massive.” While the paper is mathematically rigorous, there are some fascinating graphics that all should find of interest.

As scientific data produces results which take them to the limits of the accuracy of the scientific models, it is inevitable that the models will need some modification, or some tweaking. Such is the case now with our models of the clustering of galaxies. In a paper released last Friday, submitted to the Royal Academy of Sciences, an international group of astronomers have announced that the most accurate data now available, with respect to the formation and clustering of galaxies, requires the current models to be modified. Although the authors note that “differences between the clustering predictions of current galaxy formation models and observations are small,” the authors find that the current data requires upgrading the existing models. New physical processes are required to explain the small differences between the observations and the models. The two processes that these astronomers placed into the current models, which made the models better fit the data included “mergers between satellite galaxies and the tidal disruption of satellites.” Learn more about the scientific process and the formation of galactic clusters online now here.

You can learn more about new computer models that simulate the merging of galaxies online now at http://xxx.lanl.gov/PS_cache/arxiv/pdf/0902/0902.3001v1.pdf However, if you are into the animations that these computer models generate, take a look at one of the four animations available online at http://www.slac.stanford.edu/~mornkr/webpics/selected_movies_GM.html Don’t forget that what you are watching is taking place over hundreds of thousands of light years (in distance) and hundreds of millions of years in time.

You hear a lot about supernovae explosions, but did you ever think what it’s like to be there when a Type II (core-collapse) supernova explodes? In a paper released today, Canadian astronomers provide the latest computer simulations of Type II supernovae. You can see their animations, which have been enhanced with the effects of the additional heating caused by neutrinos, online at http://www.cita.utoronto.ca/~fernandez/alpha_movies.html And if you wish to read about how these simulations were done, you can read their paper online at http://xxx.lanl.gov/PS_cache/arxiv/pdf/0812/0812.4574v1.pdf