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Curtain eruptions from Enceladus’ south-polar terrain


Observations of the south pole of the Saturnian moon Enceladus revealed large rifts in the south-polar terrain, informally called ‘tiger stripes’, named Alexandria, Baghdad, Cairo and Damascus Sulci. These fractures have been shown to be the sources of the observed jets of water vapour and icy particles1,2,3,4 and to exhibit higher temperatures than the surrounding terrain5,6. Subsequent observations have focused on obtaining close-up imaging of this region to better characterize these emissions. Recent work7 examined those newer data sets and used triangulation of discrete jets3 to produce maps of jetting activity at various times. Here we show that much of the eruptive activity can be explained by broad, curtain-like eruptions. Optical illusions in the curtain eruptions resulting from a combination of viewing direction and local fracture geometry produce image features that were probably misinterpreted previously as discrete jets. We present maps of the total emission along the fractures, rather than just the jet-like component, for five times during an approximately one-year period in 2009 and 2010. An accurate picture of the style, timing and spatial distribution of the south-polar eruptions is crucial to evaluating theories for the mechanism controlling the eruptions.

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Figure 1: Curtain simulations illustrating the phantom jet phenomenon.
Figure 2: Schematic illustrating the dependence of phantom jet locations on viewing angle.
Figure 3: Shadow anomalies and spreading curtains.
Figure 4: Stereographic projections of the south-polar terrain showing activity at five different times, and the average.

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  1. Porco, C. C. et al. Cassini observes the active south pole of Enceladus. Science 311, 1393–1401 (2006)

    Article  ADS  CAS  PubMed  Google Scholar 

  2. Hansen, C. J. et al. Enceladus’ water vapor plume. Science 311, 1422–1425 (2006)

    Article  ADS  CAS  PubMed  Google Scholar 

  3. Spitale, J. N. & Porco, C. C. Association of the jets of Enceladus with the warmest regions on its south-polar fractures. Nature 449, 695–697 (2007)

    Article  ADS  CAS  PubMed  Google Scholar 

  4. Hansen, C. J. et al. Water vapour jets inside the plume of gas leaving Enceladus. Nature 456, 477–479 (2008)

    Article  ADS  CAS  PubMed  Google Scholar 

  5. Spencer, J. R. et al. Cassini encounters Enceladus: background and the discovery of a south polar hot spot. Science 311, 1401–1405 (2006)

    Article  ADS  CAS  PubMed  Google Scholar 

  6. Howett, C. J. A., Spencer, J. R., Pearl, J. & Segura, M. High heat flow from Enceladus’ south polar region measured using 10–600 cm−1 Cassini/CIRS data. J. Geophys. Res. 116, E03003 (2011)

    Article  ADS  Google Scholar 

  7. Porco, C. C., DiNino, D. & Nimmo, F. How the geysers, tidal stresses, and thermal emission across the south polar terrain of Enceladus are related. Astron. J. 148, 45 (2014)

    Article  ADS  Google Scholar 

  8. Porco, C. C. et al. Cassini imaging science: instrument characteristics and anticipated scientific investigations at Saturn. Space Sci. Rev. 115, 363–497 (2004)

    Article  ADS  Google Scholar 

  9. Roatsch, T. J. et al. in Saturn from Cassini-Huygens (eds Dougherty, M. Esposito, L. & Krimigis, S. ) 763–781 (Springer, 2009).

    Book  Google Scholar 

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This work was funded by grant number NNX13AG45G of the Cassini Data Analysis and Participating Scientists Program. We thank M. Hedman, P. Thomas and C. Howett for conversations on this topic.

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Authors and Affiliations



J.N.S. devised the approach and wrote the majority of the text. T.A.H. and A.R.R. contributed substantially to the interpretation and to the text. E.E.B. and S.S.P. digitized many of the fractures and contributed to early efforts that led to the current approach.

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Correspondence to Joseph N. Spitale.

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The authors declare no competing financial interests.

Extended data figures and tables

Extended Data Figure 1 Portion of image N1602274088 showing source locations inferred from anomalous emission near Damascus Sulcus.

Diamonds are sample points inferred from the observed curtains; uncertainties are shown as circles about each displayed sample point. The inferred source locations correspond well with features that are not apparent in the base map.

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Spitale, J., Hurford, T., Rhoden, A. et al. Curtain eruptions from Enceladus’ south-polar terrain. Nature 521, 57–60 (2015).

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