Warped and Hooked : Mapping the Magellanic Clouds in Three Dimensions Using Red Clump Stars
(2026) In Astrophysical Journal 1003(1).- Abstract
The Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) are the Milky Way’s nearest interacting galaxy pair, offering a unique laboratory for studying tidal effects on galactic disks. Despite extensive survey efforts, the 3D geometry of the Magellanic Clouds, particularly the putative warp of the LMC, remains poorly constrained due to incompleteness in their crowded centers and the low stellar density of their peripheries, which demand wide-field coverage. Using red clump (RC) stars as standard candles, corrected for age- and metallicity-dependent population effects with empirically calibrated color–magnitude relations and spatially resolved star formation histories, we construct the most detailed distance map of the... (More)
The Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) are the Milky Way’s nearest interacting galaxy pair, offering a unique laboratory for studying tidal effects on galactic disks. Despite extensive survey efforts, the 3D geometry of the Magellanic Clouds, particularly the putative warp of the LMC, remains poorly constrained due to incompleteness in their crowded centers and the low stellar density of their peripheries, which demand wide-field coverage. Using red clump (RC) stars as standard candles, corrected for age- and metallicity-dependent population effects with empirically calibrated color–magnitude relations and spatially resolved star formation histories, we construct the most detailed distance map of the Magellanic system to date. Based on ∼2.3 million RC stars from Gaia Data Release 3 combined with modern reddening maps, we measure median heliocentric distances of 50.62 ± 2.32 kpc for the LMC (to ∼23°) and 60.75 ± 2.85 kpc for the SMC (to ∼12°). The maps reveal substructures including the LMC Northern Arm, southern hooks, the Magellanic Bridge, and SMC peripheral overdensities, with refreshed distance estimates. Fitting the LMC disk within 7° yields a global inclination of (Formula presented) i=25.°32±0.°10 and a line-of-nodes position angle of (Formula presented) θ=142.°34±0.°21. Most strikingly, we find the LMC periphery is warped azimuthally into a U-shaped structure reaching a vertical amplitude of ∼7 kpc at a radius of ∼15 kpc. In future work, we will perform detailed comparisons with live N-body simulations to assess possible formation scenarios for the LMC warp.
(Less)
- author
- Oden, Slater J.
; Nidever, David L.
; Povick, Joshua
LU
; Massana, Pol
; Choi, Yumi
; van der Marel, Roeland P.
; Cioni, Maria Rosa L.
; Sakowska, Joanna
; Olsen, Knut A.G.
; Cullinane, Lara
; Horta, Danny
; Almeida, Andres
; Carballo-Bello, J. A.
; Crnojević, D.
; Ferguson, P. S.
; Martínez-Vázquez, C. E.
; Medina, G. E.
; Mutlu-Pakdil, B.
; Navabi, M.
; Pace, A. B.
; Riley, A. H.
LU
; Stringfellow, Guy S.
; Vivas, A. K.
and James, David J.
(Less) - organization
- publishing date
- 2026-05-20
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Dwarf galaxies (416), Magellanic Clouds (990), Red giant clump (1370), Stellar populations (1622), Stellar structures (1631)
- in
- Astrophysical Journal
- volume
- 1003
- issue
- 1
- article number
- 9
- publisher
- American Astronomical Society
- external identifiers
-
- scopus:105038412012
- ISSN
- 0004-637X
- DOI
- 10.3847/1538-4357/ae5c9e
- language
- English
- LU publication?
- yes
- id
- 32e66ab7-e93a-45ae-8b98-f1834b4dedf4
- date added to LUP
- 2026-07-09 15:19:18
- date last changed
- 2026-07-09 15:19:36
@article{32e66ab7-e93a-45ae-8b98-f1834b4dedf4,
abstract = {{<p>The Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) are the Milky Way’s nearest interacting galaxy pair, offering a unique laboratory for studying tidal effects on galactic disks. Despite extensive survey efforts, the 3D geometry of the Magellanic Clouds, particularly the putative warp of the LMC, remains poorly constrained due to incompleteness in their crowded centers and the low stellar density of their peripheries, which demand wide-field coverage. Using red clump (RC) stars as standard candles, corrected for age- and metallicity-dependent population effects with empirically calibrated color–magnitude relations and spatially resolved star formation histories, we construct the most detailed distance map of the Magellanic system to date. Based on ∼2.3 million RC stars from Gaia Data Release 3 combined with modern reddening maps, we measure median heliocentric distances of 50.62 ± 2.32 kpc for the LMC (to ∼23°) and 60.75 ± 2.85 kpc for the SMC (to ∼12°). The maps reveal substructures including the LMC Northern Arm, southern hooks, the Magellanic Bridge, and SMC peripheral overdensities, with refreshed distance estimates. Fitting the LMC disk within 7° yields a global inclination of (Formula presented) i=25.°32±0.°10 and a line-of-nodes position angle of (Formula presented) θ=142.°34±0.°21. Most strikingly, we find the LMC periphery is warped azimuthally into a U-shaped structure reaching a vertical amplitude of ∼7 kpc at a radius of ∼15 kpc. In future work, we will perform detailed comparisons with live N-body simulations to assess possible formation scenarios for the LMC warp.</p>}},
author = {{Oden, Slater J. and Nidever, David L. and Povick, Joshua and Massana, Pol and Choi, Yumi and van der Marel, Roeland P. and Cioni, Maria Rosa L. and Sakowska, Joanna and Olsen, Knut A.G. and Cullinane, Lara and Horta, Danny and Almeida, Andres and Carballo-Bello, J. A. and Crnojević, D. and Ferguson, P. S. and Martínez-Vázquez, C. E. and Medina, G. E. and Mutlu-Pakdil, B. and Navabi, M. and Pace, A. B. and Riley, A. H. and Stringfellow, Guy S. and Vivas, A. K. and James, David J.}},
issn = {{0004-637X}},
keywords = {{Dwarf galaxies (416); Magellanic Clouds (990); Red giant clump (1370); Stellar populations (1622); Stellar structures (1631)}},
language = {{eng}},
month = {{05}},
number = {{1}},
publisher = {{American Astronomical Society}},
series = {{Astrophysical Journal}},
title = {{Warped and Hooked : Mapping the Magellanic Clouds in Three Dimensions Using Red Clump Stars}},
url = {{http://dx.doi.org/10.3847/1538-4357/ae5c9e}},
doi = {{10.3847/1538-4357/ae5c9e}},
volume = {{1003}},
year = {{2026}},
}