3D shape of Orion A from Gaia DR2
- Autor(en)
- Josefa E. Großschedl, João Alves, Stefan Meingast, Christine Ackerl, Joana Ascenso, Hervé Bouy, Andreas Burkert, Jan Forbrich, Verena Fürnkranz, Alyssa Goodman, Alvaro Hacar Gonzalez, Gabor Herbst-Kiss, Charles J. Lada, Irati Larreina, Kieran Leschinski, Marco Lombardi, André Moitinho, Daniel Mortimer, Eleonora Zari
- Abstrakt
We use the Gaia DR2 distances of about 700 mid-infrared selected young stellar objects in the benchmark giant molecular cloud Orion A to infer its 3D shape and orientation. We find that Orion A is not the fairly straight filamentary cloud that we see in (2D) projection, but instead a cometary-like cloud oriented toward the Galactic plane, with two distinct components: A denser and enhanced star-forming (bent) Head, and a lower density and star-formation quieter ∼75 pc long Tail. The true extent of Orion A is not the projected ∼40 pc but ∼90 pc, making it by far the largest molecular cloud in the local neighborhood. Its aspect ratio (∼30:1) and high column-density fraction (∼45%) make it similar to large-scale Milky Way filaments ("bones"), despite its distance to the galactic mid-plane being an order of magnitude larger than typically found for these structures.
- Organisation(en)
- Institut für Astrophysik, Forschungsverbund Data Science
- Externe Organisation(en)
- Universidade do Porto, Université Bordeaux Montaigne, Ludwig-Maximilians-Universität München, Max-Planck-Institut für extraterrestrische Physik, University of Hertfordshire, Harvard-Smithsonian Center for Astrophysics, Università degli Studi di Milano-Bicocca, Universidade de Lisboa, University of Cambridge, Leiden University
- Journal
- Astronomy & Astrophysics
- Band
- 619
- Anzahl der Seiten
- 9
- ISSN
- 0004-6361
- DOI
- https://doi.org/10.1051/0004-6361/201833901
- Publikationsdatum
- 11-2018
- Peer-reviewed
- Ja
- ÖFOS 2012
- 103003 Astronomie, 103004 Astrophysik
- Schlagwörter
- ASJC Scopus Sachgebiete
- Astronomy and Astrophysics, Space and Planetary Science
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/d1c9963e-234a-4d00-a41c-bd886178daff