Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Mid-infrared images of β Pictoris and the possible role of planetesimal collisions in the central disk


When viewed in optical starlight scattered by dust, the nearly edge-on debris disk surrounding the A5V star β Pictoris (distance 19.3 pc; ref. 1) extends farther than 1,450 au from the star2. Its large-scale complexity has been well characterized, but the detailed structure of the disk's central 200-au region has remained elusive. This region is of special interest, because planets may have formed there during the star's 10–20-million-year lifetime3,4, perhaps resulting in both the observed tilt of 4.6 degrees relative to the large-scale main disk5,6 and the partial clearing of the innermost dust7,8,9. A peculiarity of the central disk (also possibly related to the presence of planets) is the asymmetry in the brightness of the ‘wings’9,10, in which the southwestern wing is brighter and more extended at 12 µm than the northeastern wing. Here we present thermal infrared images of the central disk that imply that the brightness asymmetry results from the presence of a bright clump composed of particles that may differ in size from dust elsewhere in the disk. We suggest that this clump results from the collisional grinding of resonantly trapped planetesimals or the cataclysmic break-up of a planetesimal.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Get just this article for as long as you need it


Prices may be subject to local taxes which are calculated during checkout

Figure 1: β Pic mid-infrared images.
Figure 2: SW flux divided by NE flux versus distance from star.
Figure 3: The residual emission.
Figure 4: Disk spectral energy distributions.
Figure 5: Model distributions for the NE side of disk.


  1. Crifo, F., Vidal-Madjar, A., Lallement, R., Ferlet, R. & Gerbaldi, M. β Pictoris revisited by Hipparcos. Star properties. Astron. Astrophys. 320, L29–L32 (1997)

    ADS  Google Scholar 

  2. Larwood, J. D. & Kalas, P. G. Close stellar encounters with planetesimal disks: the dynamics of asymmetry in the β Pictoris system. Mon. Not. R. Astron. Soc. 323, 402–416 (2001)

    Article  ADS  Google Scholar 

  3. Barrado y Navascués, D., Stauffer, J. R., Song, I. & Caillault, J.-P. The age of Beta Pictoris. Astrophys. J. 520, L123–L126 (1999)

    Article  ADS  Google Scholar 

  4. Zuckerman, B., Song, I., Bessell, M. S. & Webb, R. A. The β Pictoris moving group. Astrophys. J. 562, L87–L90 (2001)

    Article  ADS  Google Scholar 

  5. Heap, S. et al. Space telescope imaging spectrograph coronagraphic observations of β Pictoris. Astrophys. J. 539, 435–444 (2000)

    Article  ADS  Google Scholar 

  6. Mouillet, D., Larwood, J. D., Papaloizou, J. C. B. & Lagrange, A. M. A planet on an inclined orbit as an explanation of the warp in the β Pictoris disc. Mon. Not. R. Astron. Soc. 292, 896–904 (1997)

    Article  ADS  Google Scholar 

  7. Telesco, C. M., Becklin, E. E., Wolstencroft, R. D. & Decher, R. Resolution of the circumstellar disk of β Pictoris at 10 and 20 µm. Nature 335, 51–53 (1988)

    Article  ADS  Google Scholar 

  8. Backman, D. E., Gillett, F. C. & Witteborn, F. C. Infrared observations and thermal models of the β Pictoris dust disk. Astrophys. J. 385, 670–679 (1992)

    Article  ADS  Google Scholar 

  9. Lagage, P. O. & Pantin, E. Dust depletion in the inner disk of Beta Pictoris as a possible indicator of planets. Nature 369, 628–630 (1994)

    Article  ADS  Google Scholar 

  10. Pantin, E., Lagage, P. O. & Artymowicz, P. Mid-infrared images and models of the β Pictoris dust disk. Astron. Astrophys. 327, 1123–1136 (1997)

    ADS  Google Scholar 

  11. Weinberger, A. J., Becklin, E. E. & Zuckerman, B. The first spatially resolved mid-infrared spectroscopy of β Pictoris. Astrophys. J. 584, L33–L37 (2003)

    Article  ADS  CAS  Google Scholar 

  12. Wahhaj, Z. et al. The inner rings of β Pictoris. Astrophys. J. 584, L27–L31 (2003)

    Article  ADS  Google Scholar 

  13. Okamoto, Y. K. et al. An extrasolar planetary system revealed by planetesimal belts in β Pictoris. Nature 431, 660–662 (2004)

    Article  ADS  CAS  Google Scholar 

  14. Li, A. & Greenberg, J. M. A comet dust model for the β Pictoris disk. Astron. Astrophys. 331, 291–313 (1998)

    ADS  Google Scholar 

  15. Ozernoy, L. M., Gorkavyi, N. N., Mather, J. C. & Taidakova, T. A. Signatures of exosolar planets in dust disks. Astrophys. J. 537, L147–L151 (2000)

    Article  ADS  CAS  Google Scholar 

  16. Sicardy, B., Beaugé, C., Ferraz-Mello, S., Lazzaro, D. & Roques, F. Capture of grains into resonances through Poynting-Robertson drag. Celest. Mech. Dyn. Astron. 57, 373–390 (1993)

    Article  ADS  Google Scholar 

  17. Dermott, S. F., Jayaraman, S., Xu, Y. L., Gustafson, B. & Liou, J. C. A circumsolar ring of asteroidal dust in resonant lock with the Earth. Nature 369, 719–723 (1994)

    Article  ADS  Google Scholar 

  18. Wyatt, M. C. et al. How observations of circumstellar disk asymmetries can reveal hidden planets: pericenter glow and its application to the HR4796 disk. Astrophys. J. 527, 918–944 (1999)

    Article  ADS  Google Scholar 

  19. Wyatt, M. C. Resonant trapping of planetesimals by planet migration: debris disk clumps and Vega's similarity to the Solar System. Astrophys. J. 598, 1321–1340 (2003)

    Article  ADS  Google Scholar 

  20. Lagrange-Henri, A. M., Vidal-Madjar, A. & Ferlet, R. The β Pictoris circumstellar disk. VI. Evidence for material falling on to the star. Astron. Astrophys. 190, 275–282 (1988)

    ADS  CAS  Google Scholar 

  21. Beust, H., Vidal-Madjar, A., Ferlat, R. & Lagrange-Henri, A. M. Cometary-like bodies in the protoplanetary disk around β Pictoris. Astrophys. Space Sci. 212, 147–157 (1994)

    Article  ADS  CAS  Google Scholar 

  22. Wyatt, M. C. & Dent, W. R. F. Collisional processes in extrasolar planetesimal discs—dust clumps in Fomalhaut's debris disc. Mon. Not. R. Astron. Soc. 334, 589–607 (2002)

    Article  ADS  Google Scholar 

  23. Brandeker, A., Liseau, R., Olofsson, G. & Fridlund, M. The spatial structure of the β Pictoris gas disk. Astron. Astrophys. 413, 681–691 (2004)

    Article  ADS  CAS  Google Scholar 

  24. Dominik, C. & Decin, G. Age dependence of the Vega phenomenon: theory. Astrophys. J. 598, 626–635 (2003)

    Article  ADS  CAS  Google Scholar 

  25. Hartmann, W. K. & Davis, D. R. Satellite-sized planetesimals and lunar origin. Icarus 24, 504–515 (1975)

    Article  ADS  Google Scholar 

  26. Dermott, S. F., Kehoe, T. J. J., Durda, D. D., Grogan, K. & Nesvorný, D. in Asteroids, Comets, and Meteors 2002 (ed. Warmbein, B.) ESA SP-500, 319–322 (Publications Division, Noordwijk, 2002)

    Google Scholar 

  27. Kenyon, S. J. & Bromley, B. C. Detecting the dusty debris of terrestrial planet formation. Astrophys. J. 602, L133–L136 (2004)

    Article  ADS  Google Scholar 

  28. Van Paradijs, J., Telesco, C. M., Kouveliotou, C. & Fishman, G. J. 10 micron detection of the hard x-ray transient GRO J0422+32: free-free emission from an x-ray-driven accretion disk wind? Astrophys. J. 429, L19–L23 (1994)

    Article  ADS  Google Scholar 

Download references


We dedicate this paper to the memory of our colleague F. Gillett, infrared astronomy pioneer and co-discoverer of circumstellar debris disks. We thank K. Hanna, J. Julian and R. Piña for contributions to the success of T-ReCS; F. Varosi for assistance with data reduction; the Gemini Observatory staff in Chile, particularly M.-C. Hainaut-Rouelle, for technical assistance; and D. Simons of Gemini Observatory for support. This paper is based on observations (programme number GS-2003B-14) obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Particle Physics and Astronomy Research Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil) and CONICET (Argentina). This research was funded in part by an NSF grant to C.M.T.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Charles M. Telesco.

Ethics declarations

Competing interests

The authors declare that they have no competing financial interests.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Telesco, C., Fisher, R., Wyatt, M. et al. Mid-infrared images of β Pictoris and the possible role of planetesimal collisions in the central disk. Nature 433, 133–136 (2005).

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI:

This article is cited by


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing