@booklet {28359,
	title = {Constraints on the structure and seasonal variations of Triton{\textquoteright}s atmosphere from the 5 October 2017 stellar occultation and previous observations},
	year = {2022},
	month = {2022/01/1},
	pages = {arXiv:2201.10450},
	abstract = {A stellar occultation by Neptune{\textquoteright}s main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of which yielded a central flash detection. We aimed at constraining Triton{\textquoteright}s atmospheric structure and the seasonal variations of its atmospheric pressure since the Voyager 2 epoch (1989). We also derived the shape of the lower atmosphere from central flash analysis. We used Abel inversions and direct ray-tracing code to provide the density, pressure, and temperature profiles in the altitude range $\sim$8 km to $\sim$190 km, corresponding to pressure levels from 9 {\mu}bar down to a few nanobars. Results. (i) A pressure of 1.18$\pm$0.03 {\mu}bar is found at a reference radius of 1400 km (47 km altitude). (ii) A new analysis of the Voyager 2 radio science occultation shows that this is consistent with an extrapolation of pressure down to the surface pressure obtained in 1989. (iii) A survey of occultations obtained between 1989 and 2017 suggests that an enhancement in surface pressure as reported during the 1990s might be real, but debatable, due to very few high S/N light curves and data accessible for reanalysis. The volatile transport model analysed supports a moderate increase in surface pressure, with a maximum value around 2005-2015 no higher than 23 {\mu}bar. The pressures observed in 1995-1997 and 2017 appear mutually inconsistent with the volatile transport model presented here. (iv) The central flash structure does not show evidence of an atmospheric distortion. We find an upper limit of 0.0011 for the apparent oblateness of the atmosphere near the 8 km altitude.},
	keywords = {Astrophysics - Earth and Planetary Astrophysics},
	url = {https://ui.adsabs.harvard.edu/abs/2022arXiv220110450M},
	author = {Marques Oliveira, J. and Sicardy, B. and Gomes-J{\'u}nior, A. R. and Ortiz, J. L. and Strobel, D. F. and Bertrand, T. and Forget, F. and Lellouch, E. and Desmars, J. and B{\'e}rard, D. and Doressoundiram, A. and Lecacheux, J. and Leiva, R. and Meza, E. and Roques, F. and Souami, D. and Widemann, T. and Santos-Sanz, P. and Morales, N. and Duffard, R. and Fern{\'a}ndez-Valenzuela, E. and Castro-Tirado, A. J. and Braga-Ribas, F. and Morgado, B. E. and Assafin, M. and Camargo, J. I. B. and Vieira-Martins, R. and Benedetti-Rossi, G. and Santos-Filho, S. and Banda-Huarca, M. V. and Quispe-Huaynasi, F. and Pereira, C. L. and Rommel, F. L. and Margoti, G. and Dias-Oliveira, A. and Colas, F. and Berthier, J. and Renner, S. and Hueso, R. and P{\'e}rez-Hoyos, S. and S{\'a}nchez-Lavega, A. and Rojas, J. F. and Beisker, W. and Kretlow, M. and Herald, D. and Gault, D. and Bath, K. -L. and Bode, H. -J. and Bredner, E. and Guhl, K. and Haymes, T. V. and Hummel, E. and Kattentidt, B. and Kl{\"o}s, O. and Pratt, A. and Thome, B. and Avdellidou, C. and Gazeas, K. and Karampotsiou, E. and Tzouganatos, L. and Kardasis, E. and Christou, A. A. and Xilouris, EM and Alikakos, I. and Gourzelas, A. and Liakos, A. and Charmandaris, V and Jel{\'\i}nek, M. and {\v S}trobl, J. and Eberle, A. and Rapp, K. and G{\"a}hrken, B. and Klemt, B. and Kowollik, S. and Bitzer, R. and Miller, M. and Herzogenrath, G. and Frangenberg, D. and Brandis, L. and P{\"u}tz, I. and Perdelwitz, V. and Piehler, G. M. and Riepe, P. and von Poschinger, K. and Baruffetti, P. and Cenadelli, D. and Christille, J. -M. and Ciabattari, F. and Di Luca, R. and Alboresi, D. and Leto, G. and Zanmar Sanchez, R. and Bruno, P. and Occhipinti, G. and Morrone, L. and Cupolino, L. and Noschese, A. and Vecchione, A. and Scalia, C. and Lo Savio, R. and Giardina, G. and Kamoun, S. and Barbosa, R. and Behrend, R. and Spano, M. and Bouchet, E. and Cottier, M. and Falco, L. and Gallego, S. and Tortorelli, L. and Sposetti, S. and Sussenbach, J. and Van Den Abbeel, F. and Andr{\'e}, P. and Llibre, M. and Pailler, F. and Ardissone, J. and Boutet, M. and Sanchez, J. and Bretton, M. and Cailleau, A. and Pic, V. and Granier, L. and Chauvet, R. and Conjat, M. and Dauvergne, J. L. and Dechambre, O. and Delay, P. and Delcroix, M. and Rousselot, L. and Ferreira, J. and Machado, P. and Tanga, P. and Rivet, J. -P. and Frappa, E. and Irzyk, M. and Jabet, F. and Kaschinski, M. and Klotz, A. and Rieugnie, Y. and Klotz, A. N. and Labrevoir, O. and Lavandier, D. and Walliang, D. and Leroy, A. and Bouley, S. and Lisciandra, S. and Coliac, J. -F. and Metz, F. and Erpelding, D. and Nougayr{\`e}de, P. and Midavaine, T. and Miniou, M. and Moindrot, S. and Morel, P. and Reginato, B. and Reginato, E. and Rudelle, J. and Tregon, B. and Tanguy, R. and David, J. and Thuillot, W. and Hestroffer, D. and Vaudescal, G. and Baba Aissa, D. and Grigahcene, Z. and Briggs, D. and Broadbent, S. and Denyer, P. and Haigh, N. J. and Quinn, N. and Thurston, G. and Fossey, S. J. and Arena, C. and Jennings, M. and Talbot, J. and Alonso, S. and Rom{\'a}n Reche, A. and Casanova, V. and Briggs, E. and Iglesias-Marzoa, R. and Abril Ib{\'a}{\~n}ez, J. and D{\'\i}az Mart{\'\i}n, M. C. and Gonz{\'a}lez, H. and Maestre Garc{\'\i}a, J. L. and Marchant, J. and Ordonez-Etxeberria, I. and Martorell, P. and Salamero, J. and Organero, F. and Ana, L. and Fonseca, F. and Peris, V. and Brevia, O. and Selva, A. and Perello, C. and Cabedo, V. and Gon{\c c}alves, R. and Ferreira, M. and Marques Dias, F. and Daassou, A. and Barkaoui, K. and Benkhaldoun, Z. and Guennoun, M. and Chouqar, J. and Jehin, E. and Rinner, C. and Lloyd, J. and El Moutamid, M. and Lamarche, C. and Pollock, J. T. and Caton, D. B. and Kouprianov, V. and Timerson, B. W. and Blanchard, G. and Payet, B. and Peyrot, A. and Teng-Chuen-Yu, J. -P. and Fran{\c c}oise, J. and Mondon, B. and Payet, T. and Boissel, C. and Castets, M. and Hubbard, W. B. and Hill, R. and Reitsema, H. J. and Mousis, O. and Ball, L. and Neilsen, G. and Hutcheon, S. and Lay, K. and Anderson, P. and Moy, M. and Jonsen, M. and Pink, I. and Walters, R. and Downs, B.}
}
