Searching for Extragalactic Exoplanetary Systems: The Curious Case of BD+20 2457

  title={Searching for Extragalactic Exoplanetary Systems: The Curious Case of BD+20 2457},
  author={H{\'e}lio D. Perottoni and Jo{\~a}o A. S. Amarante and Guilherme Limberg and Helio J. Rocha-Pinto and Silvia Rossi and Friedrich Anders and Lais Borbolato},
  journal={The Astrophysical Journal Letters},
Planets and their host stars carry a long-term memory of their origin in their chemical compositions. Thus, identifying planets formed in different environments improves our understating of planetary formation. Although restricted to detecting exoplanets within the solar vicinity, we might be able to detect planetary systems that formed in small external galaxies and later merged with the Milky Way. In fact, Gaia data have unequivocally shown that the Galaxy underwent several significant minor… 
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  • A. Helmi
  • Physics
    Annual Review of Astronomy and Astrophysics
  • 2020
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