The Spiral Structure of the Outer Milky Way in Hydrogen
Abstract
We produce a detailed map of the perturbed surface density of neutral hydrogen in the outer Milky Way disk, demonstrating that the Galaxy is a non-axisymmetric multiarmed spiral. Spiral structure in the southern half of the Galaxy can be traced out to at least 25 kiloparsecs, implying a minimum radius for the gas disk. Overdensities in the surface density are coincident with regions of reduced gas thickness. The ratio of the surface density to the local median surface density is relatively constant along an arm. Logarithmic spirals can be fit to the arms with pitch angles of 20° to 25°.
Get full access to this article
View all available purchase options and get full access to this article.
References and Notes
1
H. C. van de Hulst, C. A. Muller, J. H. Oort, Bull. Astron. Inst. Neth.12, 117 (1954).
2
F. Kerr, G. Westerhout, in Galactic Structure, vol. 5 of Stars and Stellar Systems, A. Blaauw, M. Schmidt, Eds. (Univ. Chicago Press, Chicago, IL, 1965), pp. 167–202.
3
A. P. Henderson, P. D. Jackson, F. J. Kerr, Astrophys. J.263, 116 (1982).
4
D. Malin, Am. Astron. Soc. Photo Bull.16, 10 (1977).
5
P. M. W. Kalberla et al., Astron. Astrophys.440, 775 (2005).
6
D. Hartmann, W. B. Burton, Atlas of Galactic Neutral Hydrogen (Cambridge Univ. Press, Cambridge, 1997).
7
E. Bajaja et al., Astron. Astrophys.440, 767 (2005).
8
E. M. Arnal, E. Bajaja, J. J. Larrarte, R. Morras, W. G. L. Pöppel, Astron. Astrophys. Suppl. Ser.142, 35 (2000).
9
M. J. Reid, Annu. Rev. Astron. Astrophys.31, 345 (1993).
10
R. P. Olling, M. R. Merrifield, Mon. Not. R. Astron. Soc.297, 943 (1998).
11
E. S. Levine, L. Blitz, C. Heiles, Astrophys. J.643, 881 (2006).
12
N. M. McClure-Griffiths, J. M. Dickey, B. M. Gaensler, A. J. Green, Astrophys. J.607, L127 (2004).
13
J. S. Miller, Astrophys. J.151, 473 (1968).
14
Y. Xu, M. J. Reid, X. W. Zheng, K. M. Menten, Science311, 54 (2006); published online 7December 2005.
15
W. B. Burton, Astron. Astrophys.10, 76 (1971).
16
M. A. Tuve, S. Lundsager, Astron. J.77, 652 (1972).
17
C. Yuan, Astrophys. J.158, 871 (1969).
18
N. H. Dieter, Astron. Astrophys.12, 59 (1971).
19
G. R. Knapp, S. D. Tremaine, J. E. Gunn, Astron. J.83, 1585 (1978).
20
J. P. Vallée, Astron. J.130, 569 (2005).
21
W. W. Morgan, A. E. Whitford, A. D. Code, Astrophys. J.118, 318 (1953).
22
Y. M. Georgelin, Y. P. Georgelin, Astron. Astrophys.49, 57 (1976).
23
R. J. Wainscoat, M. Cohen, K. Volk, H. J. Walker, D. E. Schwartz, Astrophys. J. Suppl. Ser.83, 111 (1992).
24
We thank P. Kalberla for providing a copy of the LAB HI survey and J. Peek, C. Laver, and T. Robishaw for helpful advice regarding plots. E.S.L. and L.B. were supported by NSF grant AST 02-28963. C.H. was supported by NSF grant AST 04-06987.
(0)eLetters
eLetters is a forum for ongoing peer review. eLetters are not edited, proofread, or indexed, but they are screened. eLetters should provide substantive and scholarly commentary on the article. Embedded figures cannot be submitted, and we discourage the use of figures within eLetters in general. If a figure is essential, please include a link to the figure within the text of the eLetter. Please read our Terms of Service before submitting an eLetter.
Log In to Submit a ResponseNo eLetters have been published for this article yet.
Information & Authors
Information
Published In
Science
Volume 312 | Issue 5781
23 June 2006
23 June 2006
Copyright
American Association for the Advancement of Science.
Article versions
You are viewing the most recent version of this article.
Submission history
Received: 7 April 2006
Accepted: 22 May 2006
Published in print: 23 June 2006
Authors
Metrics & Citations
Metrics
Article Usage
Altmetrics
Citations
Cite as
- E. S. Levine et al.
Export citation
Select the format you want to export the citation of this publication.
Cited by
- Building an Acceleration Ladder with Tidal Streams and Pulsar Timing, The Astrophysical Journal Letters, 945, 2, (L32), (2023).https://doi.org/10.3847/2041-8213/acba15
- A Three-dimensional Map of the Milky Way Using 66,000 Mira Variable Stars, The Astrophysical Journal Supplement Series, 264, 1, (20), (2023).https://doi.org/10.3847/1538-4365/acad7a
- Evidence for Population-dependent Vertical Motions and the Long-lived Nonsteady Lopsided Milky Way Warp, The Astrophysical Journal, 943, 2, (88), (2023).https://doi.org/10.3847/1538-4357/acab5b
- Two-point Correlation Function Studies for the Milky Way: Discovery of Spatial Clustering from Disk Excitations and Substructure, The Astrophysical Journal, 942, 1, (41), (2023).https://doi.org/10.3847/1538-4357/ac9ccc
- Redetermination of the Parameters of the Galactic Spiral Pattern from Classical Cepheids, Astronomy Letters, 48, 10, (568-577), (2023).https://doi.org/10.1134/S106377372209002X
- A new resonance-like feature in the outer disc of the Milky Way, Astronomy & Astrophysics, 670, (A10), (2023).https://doi.org/10.1051/0004-6361/202244605
- Bayesian inference of three-dimensional gas maps, Astronomy & Astrophysics, 671, (A54), (2023).https://doi.org/10.1051/0004-6361/202243326
- Interstellar Absorption and Dust Scattering, Handbook of X-ray and Gamma-ray Astrophysics, (1-39), (2023).https://doi.org/10.1007/978-981-16-4544-0_93-1
- Local Spiral Structure Traced by Red Clump Stars, The Astrophysical Journal, 931, 1, (72), (2022).https://doi.org/10.3847/1538-4357/ac67a6
- Estimation of the Parameters of the Spiral Pattern in the Galaxy Based on a Sample of Classical Cepheids, Astronomy Letters, 48, 2, (126-137), (2022).https://doi.org/10.1134/S1063773722010017
- See more
Loading...
View Options
Check Access
Log in to view the full text
AAAS login provides access to Science for AAAS Members, and access to other journals in the Science family to users who have purchased individual subscriptions.
- Become a AAAS Member
- Activate your AAAS ID
- Purchase Access to Other Journals in the Science Family
- Account Help
Log in via OpenAthens.
Log in via Shibboleth.
More options
Register for free to read this article
As a service to the community, this article is available for free. Login or register for free to read this article.
Buy a single issue of Science for just $15 USD.