Abstract
Active galactic nuclei (AGNs) display many energetic phenomena—broad emission lines, X-rays, relativistic jets, radio lobes—originating from matter falling onto a supermassive black hole. It is widely accepted that orientation effects play a major role in explaining the observational appearance of AGNs. Seen from certain directions, circum-nuclear dust clouds would block our view of the central powerhouse1,2. Indirect evidence suggests that the dust clouds form a parsec-sized torus-shaped distribution. This explanation, however, remains unproved, as even the largest telescopes have not been able to resolve the dust structures. Here we report interferometric mid-infrared observations that spatially resolve these structures in the galaxy NGC 1068. The observations reveal warm (320 K) dust in a structure 2.1 parsec thick and 3.4 parsec in diameter, surrounding a smaller hot structure. As such a configuration of dust clouds would collapse in a time much shorter than the active phase of the AGN3, this observation requires a continual input of kinetic energy to the cloud system from a source coexistent with the AGN.
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Acknowledgements
This Letter is based on observations carried out at the European Southern Observatory, Paranal, Chile, in the framework of the VLTI science demonstration program. MIDI could not have been built without contributions from many people, including E. J. Bakker, P. Ballester, S. Beckwith, P. Biereichel, A. Böhm, W. D. Cotton, S. Damstra, A. Glindemann, B. Grimm, J. de Jong, N. Haddad, H. Hanenburg, T. Henning, N. Housen, S. Hippler, W. Laun, S. Ligori, R. Lenzen, B. Lopez, O. von der Lühe, R. J. Mathar, J. Meisner, S. Morel, W. Morr, U. Neumann, R.-R. Rohloff, P. Schuller, N. Salm, C. Storz, A. Wallander and K. Wagner. We thank ESO staff at Garching, Santiago de Chile, and Cerro Paranal (Chile), for operating MIDI.
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Jaffe, W., Meisenheimer, K., Röttgering, H. et al. The central dusty torus in the active nucleus of NGC 1068. Nature 429, 47–49 (2004). https://doi.org/10.1038/nature02531
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DOI: https://doi.org/10.1038/nature02531
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