Release of volatiles from a possible cryovolcano from near-infrared imaging of Titan

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Abstract

Titan is the only satellite in our Solar System with a dense atmosphere. The surface pressure is 1.5 bar (ref. 1) and, similar to the Earth, N2 is the main component of the atmosphere. Methane is the second most important component2, but it is photodissociated on a timescale of 107 years (ref. 3). This short timescale has led to the suggestion that Titan may possess a surface or subsurface reservoir of hydrocarbons4,5 to replenish the atmosphere. Here we report near-infrared images of Titan obtained on 26 October 2004 by the Cassini spacecraft. The images show that a widespread methane ocean does not exist; subtle albedo variations instead suggest topographical variations, as would be expected for a more solid (perhaps icy) surface. We also find a circular structure 30 km in diameter that does not resemble any features seen on other icy satellites. We propose that the structure is a dome formed by upwelling icy plumes that release methane into Titan's atmosphere.

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Figure 1: Titan's map at 2.03 µm wavelength.
Figure 2: VIMS high-resolution observations.
Figure 3: High-resolution image of Fig. 2d at different wavelengths.
Figure 4: Geological interpretation of the high-resolution image.

References

  1. 1

    Lellouch, E. Atmospheric model of Titan and Triton. Ann. Geophys. 8, 653–660 (1990)

  2. 2

    Kuiper, G. P. Titan: a satellite with an atmosphere. Astrophys. J. 100, 329–332 (1944)

  3. 3

    Yung, Y. L., Allen, M. & Pinto, J. P. Photochemistry of the atmosphere of Titan: comparison between model and observations. Astrophys. J. Suppl. 55, 465–506 (1984)

  4. 4

    Lunine, J. I. Does Titan have an ocean? A review of current understanding of Titan's surface. Rev. Geophys. 31, 133–149 (1993)

  5. 5

    Lunine, J. I., Stevenson, D. J. & Yung, Y. L. Ethane ocean on Titan. Science 222, 1229–1230 (1983)

  6. 6

    Sotin, C. & Tobie, G. Internal structure and dynamics of the large icy satellites. C.R. Acad. Sci. 5, 769–780 (2004)

  7. 7

    Meier, R., Smith, B. A., Owen, T. C. & Terrile, R. J. The surface of Titan from NICMOS observations with the Hubble Space Telescope. Icarus 145, 462–473 (2000)

  8. 8

    Brown, B. et al. Observations with the Visual and Infrared Mapping Spectrometer (VIMS) during Cassini's flyby of Jupiter. Icarus 164, 461–470 (2003)

  9. 9

    Lucchita, B. K. Grooved terrains on Ganymede. Icarus 44, 481–501 (1980)

  10. 10

    Sotin, C., Head, J. W. & Tobie, G. Europa: Tidal heating of upwelling thermal plumes and the origin of lenticulae and chaos melting. Geophys. Res. Lett. 29(8), doi:10.1029/2001GL013844 (2002)

  11. 11

    Gibbard, S. G. et al. Titan's 2-µm surface albedo and haze optical depth in 1996–2004. Geophys. Res. Lett. 31, doi:10.1029/2004GL019803 (2004)

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Acknowledgements

We thank E. Mercier, D. Mège, J.-P. Combe and O. Bourgeois for discussions about interpreting the high-resolution image, and R. Wagner for help in the projection of the cubes.

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Correspondence to C. Sotin.

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Reprints and permissions information is available at npg.nature.com/reprintsandpermissions. The authors declare no competing financial interests.

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