The Milky Way's disc of classical satellite galaxies in light of Gaia DR2
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F20%3A10423388" target="_blank" >RIV/00216208:11320/20:10423388 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=02-dcMLzQL" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=02-dcMLzQL</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1093/mnras/stz3163" target="_blank" >10.1093/mnras/stz3163</a>
Alternative languages
Result language
angličtina
Original language name
The Milky Way's disc of classical satellite galaxies in light of Gaia DR2
Original language description
We study the correlation of orbital poles of the 11 classical satellite galaxies of theMilkyWay, comparing results from previous proper motions with the independent data by Gaia DR2. Previous results on the degree of correlation and its significance are confirmed by the new data. Amajority of the satellites co-orbit along theVast Polar Structure, the plane (or disc) of satellite galaxies defined by their positions. The orbital planes of eight satellites align to <20. with a common direction, seven even orbit in the same sense. Most also share similar specific angular momenta, though their wide distribution on the sky does not support a recent group infall or satellites-of-satellites origin. The orbital pole concentration has continuously increased as more precise proper motions were measured, as expected if the underlying distribution shows true correlation that is washed out by observational uncertainties. The orbital poles of the up to seven most correlated satellites are in fact almost as concentrated as expected for the best-possible orbital alignment achievable given the satellite positions. Combining the best-available proper motions substantially increases the tension with CDM cosmological expectations: <0.1 per cent of simulated satellite systems in IllustrisTNG contain seven orbital poles as closely aligned as observed. Simulated systems that simultaneously reproduce the concentration of orbital poles and the flattening of the satellite distribution have a frequency of <0.1 per cent for any number of k > 3 combined orbital poles, indicating that these results are not affected by a look-elsewhere effect. This compounds the Planes of Satellite Galaxies Problem.
Czech name
—
Czech description
—
Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
—
OECD FORD branch
10308 - Astronomy (including astrophysics,space science)
Result continuities
Project
—
Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2020
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Monthly Notices of the Royal Astronomical Society
ISSN
0035-8711
e-ISSN
—
Volume of the periodical
491
Issue of the periodical within the volume
2
Country of publishing house
GB - UNITED KINGDOM
Number of pages
18
Pages from-to
3042-3059
UT code for WoS article
000512302100109
EID of the result in the Scopus database
2-s2.0-85079627331