Computational Planet, Star and Galaxy Formation

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Galaxies change so slowly that they appear fixed on the sky in the form of frozen beautiful nebulae lit by billions of stars. Computer simulations enable the astronomer's dream of seeing them evolve before their very eyes. When sped up so that millions of years pass in moments galaxies are dynamic places, swirling vortices where stars are constantly being born and explosively dying.******We can now artificially generate galaxies with delicate spiral patterns of sparkling gas, dust and stars indistinguishable from those nearby in the sky. The challenge is to take things to the extreme: to model galaxies as they smash together and create giant bursts of new stars and drive material into super-massive black holes with the mass of millions of stars lurking in the middle of nearly every galaxy in the sky. These mergers are commonplace in the early universe when galaxies were far more violent places, more like storm-wracked clouds than spiral disks and saturated with levels of gas, dust and radiation far above what our Milky Way Galaxy experiences today. Understanding this violent past will help us understand the universe around us today, whose stars and very elements were mostly made billions of years earlier.******This is also our future: in a billion years our Milky Way will wrap itself around the Andromeda galaxy in a frenzy that will ultimately destroy their beautiful disks as our distant descendants watch unscathed from an aging solar sytem. Amazingly, it is quite unlikely any stars will physically collide in this process. It will however, spawn rafts of new star formation, consuming the gas of both galaxies and leaving us inside a single, great elliptical galaxy in the distant future.******Our research links together radiation, gas and dust; planets, stars and galaxies. All of them are interdependent and affect the others. Supercomputers are the tool that lets us study these processes that are too slow and too difficult to study any other way. The challenge is to produce the diversity that astronomers see on the sky using amazing new instruments tuned to see everything from nearby star and planet forming gas (The Atacama Large Millimetre Array in Chile) to dust and light from early galaxies (the upcoming Thirty Meter Telescope and the James Webb Space Telescope).