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The Milky Way as the Ultimate Extragalactic Source

Boudewijn F. Roukema
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Abstract

The GAIA satellite will observe the Galaxy and its closest satellites in great detail. This should allow (i) dating past events of dwarf galaxies merging or interacting with the Galaxy, and much improved orbital parameters of the nine dwarf spheroidals and the Magellanic Clouds and (ii) dating of active galactic nucleus (AGN) phases of the Galaxy several Gigayears in the past, by detecting coeval star formation (e.g. open star clusters) that occurred along kpc scale Galactic jets. Both predictions (i) and (ii) of past history will be highly valuable for searching for or excluding topologically lensed images of the Milky Way at high redshift.

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Boudewijn F. Roukema. 2001-06-14. The Milky Way as the Ultimate Extragalactic Source. https://arxiv.org/abs/astro-ph/0106272

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