Mars; Airglow; Mars Express; nitric oxide; nightside; variability; altitude; intensity
Abstract :
[en] Limb observations with the SPICAM ultraviolet spectrometer on board the Mars
Express orbiter revealed ultraviolet nightglow emission in the delta (190–240 nm) and
gamma (225–270 nm) bands of nitric oxide. This emission arises from radiative recombination
between O(3P) and N(4S) atoms that are produced on the day side and form excited NO
molecules on the night side. In this study, we analyze the night limb observations obtained
during the MEX mission. In particular, we describe the variability of the emission
brightness and its peak altitude. We examine possible correlations with latitude, local time,
magnetic field strength or solar activity. We show that the altitude of maximum emission
varies between 55 and 92 km while the brightness is in the range 0.2 to 10.5 kR. The
total vertical emission rate ranges from 8 to 237 R with an average value of 36 ± 52 R. The
observed topside scale height of the emission profile varies between 3.8 and 11.0 km,
with a mean value of 6 ± 1.7 km. We use a chemical-diffusive atmospheric model where
the eddy coefficient, whose value in the Mars thermosphere is uncertain, is a free
parameter to match the observed peak altitude of the emission. The model solves the
continuity equation for O(3P), N(4S), and NO using a finite volume method on a
one-dimensional grid. We find that the downward flux of N atoms at 100 km varies by two
orders of magnitude, ranging from 10E7 to 10E9 atoms cm-2 s-1.
Research center :
Laboratoire de Physique Atmosphérique et Planétaire
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Cox, Cédric ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)
Saglam, Adem ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)
Gérard, Jean-Claude ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)
Bertaux, Jean-Loup
Gonzalez-Galindo, Francesco
Leblanc, François
Reberac, Aurélie
Language :
English
Title :
Distribution of the ultraviolet nitric oxide Martian night airglow: Observations from Mars Express and comparisons with a one-dimensional model
Alternative titles :
[fr] Distribution de l'airglow ultraviolet de NO sur la face nuit de Mars: Observations de la sonde Mars Express et comparaison avec un modèle unidimensionnel
Publication date :
14 August 2008
Journal title :
Journal of Geophysical Research
ISSN :
0148-0227
eISSN :
2156-2202
Publisher :
American Geophysical Union, Washington, United States - District of Columbia
Angelats i Coll, M., F. Forget, M. A. López-Valverde, and F. González-Galindo (2005), The first Mars thermospheric general circulation model: The Martian atmosphere from the ground to 240 km, Geophys. Res. Lett., 32, L04201, doi:10.1029/2004GL021368.
Atreya, S. K., and Z. G. Gu (1994), Stability of the Martian atmosphere: Is heterogeneous catalysis essential?, J. Geophys. Res., 99, 13,133-13,145.
Banks, P. M., and G. Kockarts (1973), Aeronomy, Part B, Elsevier, New York.
Bertaux, J.-L., et al. (2005), Nightglow in the upper atmosphere of Mars and implications for atmospheric transport, Science, 307, 566-569.
Campbell, I. M., and B. A. Thrush (1966), Behavior of carbon dioxide and nitrous oxide in active nitrogen, Trans. Faraday Soc., 62, 3366-3374.
Campbell, I. M., and C. N. Gray (1973), Rate constants for O(3P) recombination and association with N (4S), Chem. Phys. Lett., 18(4), 607-609.
Cohen-Sabban, J., and A. Vuillemin (1973), Ultra-violet nighiglow spectrum from 1900 Å to 3400 Å, Astrophys. Space Sci., 24, 127-132.
Dalgarno, A., J. F. Babb, and Y. Sun (1992), Radiative association in planetary atmospheres, Planet. Space Sci., 40, 243-246.
Feldman, P. D., H. W. Moos, J. T. Clarke, and A. L. Lane (1979), Identification of the UV nightglow from Venus, Nature, 279, 221-222.
Forget, F., F. Hourdin, R. Fournier, C. Hourdin, and O. Talagrand (1999), Improved general circulation models of the Martian atmosphere from the surface to above 80 km, J. Geophys. Res., 104, 24,155-24,175.
Fox, J. L. (1994), Rate coefficient for the reaction N+NO, J. Geophys. Res., 99, 6273-6276.
Fox, J. L. (1996), The Martian thermosphere/ionosphere at high and low solar activities, Adv. Space Res., 17, 203-218.
Gérard, J.-C., A. I. F. Stewart, and S. W. Bougher (1981), The altitude distribution of the Venus ultraviolet airglow and implications on vertical transport, Geophys. Res. Lett., 8, 633-636.
Groth, W., D. Kley, and U. Schurath (1971), Rate constant for the infrared emission of the NO(C2II → A2∑ +) transition, J. Quant. Spectrosc. Radiat. Transfer., 11, 1475-1480.
Kahn, R. (1990), Ice haze, snow, and the Mars water cycle, J. Geophys. Res., 95, 14,677-14,693.
Kong, T. Y., and M. B. McElroy (1977), The global distribution of O3 On Mars, Planet. Space Sci., 25, 839-857.
Krasnopolsky, V. A. (1993), Photochemistry of the Martian atmosphere (mean conditions), Icarus, 101, 313-332.
Krasnopolsky, V. A. (2002), Mars' upper atmosphere and ionosphere at low, medium, and high solar activities: Implications for evolution of water, J. Geophys. Res., 107(E12), 5128, doi:10.1029/2001JE001809.
Krasnopolsky, V. A. (2006), Photochemistry of the Martian atmosphere: Seasonal, latitudinal, and diumal variations, Icarus, 185, 153-170.
Krasnopolsky, V. A., and V. A. Parshev (1979), Ozone and photochemistry of the Martian lower atmosphere, Planet Space Sci., 27, 113-120.
Leblanc, F., J. Y. Chaufray, J. Lilensten, O. Witasse, and J.-L. Bertaux (2006), Martian dayglow as seen by the SPICAM UV spectrograph on Mars Express, J. Geophys. Res., 111, E09S11, doi:10.1029/2005JE002664.
Liu, S. C., and T. M. Donahue (1976), The regulation of hydrogen and oxygen escape from Mars, Icarus, 28, 231-246.
McElroy, M. B., and T. M. Donahue (1972), Stability of the Martian atmosphere, Science, 177, 986-988.
Nair, H., M. Allen, A. D. Anbar, Y. L. Yung, and R. T. Clancy (1994), A photochemical model of the Martian atmosphere, Icarus, 111, 124-150.
Newman, S. M., I. C. Lane, A. J. Orr-Ewing, D. A. Newnham, and J. Ballard (1999), Integrated absorption intensity and Einstein coefficients for the O2 a1Δ g-X3∑g- (0, 0) transition: A comparison of cavity ringdown and high resolution Fourier transform spectroscopy with a long-path absorption cell, J. Chem. Phys., 110, 10,749-10,757.
Purucker, M., D. Ravat, H. Frey, C. Voorhies, T. Sabaka, and M. Acuña (2000), An altitude-normalized magnetic map of Mars and its interpretation, Geophys. Res. Lett., 27, 2449-2452.
Shimazaki, T. (1989), Photochemical stability of CO2 in the Martian atmosphere: Reevaluation of the eddy diffusion coefficient and the role of water vapor, J. Geomagn. Geoelectr., 41, 273-301.
Stewart, A. I., D. E. Anderson, L. W. Esposito, and C. A. Barth (1979), Ultraviolet spectroscopy of Venus: Initial results from the Pioneer orbiter, Science, 203, 777-779.
Stewart, A. I. F., J.-C. Gerard, D. W. Rusch, and S. W. Bougher (1980), Morphology of the Venus ultraviolet night airglow, J. Geophys. Res., 85, 7861-7870.
Von Zahn, U., K. H. Fricke, H. J. Hoffmann, and K. Pelka (1979), Venus: Eddy coefficients in the thermosphere and in the inferred helium content of the lower atmosphere, Geophys. Res. Lett., 6, 337-340.
Yung, Y. L., and W. B. Demore (1982), Photochemistry of the stratosphere of Venus: Implications for atmospheric evolution, Icarus, 51, 199-247.
Yung, Y. L., J. S. Wen, J. P. Pinto, M. Allen, K. K. Pierce, and S. Paulson (1988), HDO in the Martian atmosphere: Implications for the abundance of crustal water, Icarus, 76, 146-159.