Skip to main content Accessibility help

Structure of the Milky Way: View from the Southern Hemisphere

  • Lucas J. Hyland (a1), Simon P. Ellingsen (a1) and Mark J. Reid (a2)


The exclusive association of Class II methanol masers with high mass star formation regions and in turn spiral arms, makes them ideal tracers of spiral structure. The bright and compact nature of masers also makes them good sources for Very Long Baseline Interferometry, with their fluxes visible on some of the longest terrestrial baselines. The success of the BeSSeL (Bar and Spiral Structure Legacy) project has demonstrated the use of masers in large scale high–precision trigonometric parallax surveys. This survey was then able to precisely map the spiral arms visible from the Northern Hemisphere and recalculate the fundamental Milky Way parameters R0 and θ0. The majority of the Milky Way is visible from the Southern Hemisphere and at the present time the Australian LBA (Long Baseline Array) is the only Southern Hemisphere array capable of taking high–precision trigonometric parallax data. We present the progress–to–date of the Southern Hemisphere experiment. We will also unveil a new broadband Southern Hemisphere array, capable of much faster parallax turnaround and atmospheric calibration.



Hide All
Krishnan, V., Ellingsen, S. P., Reid, M. J., et al. 2017, MRNAS, 465, 1095
Krishnan, V., Ellingsen, S. P., Reid, M. J., et al. 2015, ApJ, 805, 129
Lovell, J. E. J., McCallum, J. N., Reid, P. B., et al. 2013, Journal of Geodesy, 87, 527
Reid, M. J., Menten, K. M., Brunthaler, A., & Moellenbrock, G. A. 2009, in Astronomy, Vol. 2010, astro2010: The Astronomy and Astrophysics Decadal Survey
Reid, M. J., Menten, K. M., Zheng, X. W., et al. 2009b, ApJ, 700, 137
Reid, M. J., Menten, K. M., Brunthaler, A., et al. 2014, ApJ, 783, 130
Reid, M. J., Dame, T. M., Menten, K. M., & Brunthaler, A., 2016, ApJ, 823, 77
Rioja, M. J., Stevens, E., Gurvits, L., et al. 1997, Vistas in Astronomy, 41, 213
Rioja, M. J., Dodson, R., Orosz, G., Imai, H., & Frey, S., 2017, AJ, 153, 105
Sun, J., Böhm, J., Nilsson, T., et al. 2014, Journal of Geodesy, 88, 449
MathJax is a JavaScript display engine for mathematics. For more information see



Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed