A dynamic upper atmosphere of Venus as revealed by VIRTIS on Venus Express


The upper atmosphere of a planet is a transition region in which energy is transferred between the deeper atmosphere and outer space. Molecular emissions from the upper atmosphere (90–120 km altitude) of Venus can be used to investigate the energetics and to trace the circulation of this hitherto little-studied region. Previous spacecraft1 and ground-based2,3,4 observations of infrared emission from CO2, O2 and NO have established that photochemical and dynamic activity controls the structure of the upper atmosphere of Venus. These data, however, have left unresolved the precise altitude of the emission1 owing to a lack of data and of an adequate observing geometry5,6. Here we report measurements of day-side CO2 non-local thermodynamic equilibrium emission at 4.3 µm, extending from 90 to 120 km altitude, and of night-side O2 emission extending from 95 to 100 km. The CO2 emission peak occurs at 115 km and varies with solar zenith angle over a range of 10 km. This confirms previous modelling7, and permits the beginning of a systematic study of the variability of the emission. The O2 peak emission happens at 96 km ± 1 km, which is consistent with three-body recombination of oxygen atoms transported from the day side by a global thermospheric sub-solar to anti-solar circulation, as previously predicted8.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: CO 2 non-LTE emission on the day side of Venus.
Figure 2: O 2 emission in the night side upper atmosphere of Venus.
Figure 3: Apparent motions in the O 2 emission in nadir geometry during orbits 84 (above) and 96 (below).


  1. 1

    Bougher, S. W., Alexander, M. J. & Mayr, H. G. Upper atmosphere dynamics: global circulation and gravity waves. In Venus II: Geology, Geophysics, Atmosphere, and Solar Wind Environment (eds Bougher, S. W. Hunten, D. M. & Philips R. J.) 259–292 (Univ. Arizona Press, Tucson, 1997)

    Google Scholar 

  2. 2

    Connes, P. Noxon, J. F., Traub, W. A. & Carleton, N. O2 1Δ emission in the day and night airglow of Venus. Astrophys. J. Lett. 233, L29–L32 (1979)

    ADS  CAS  Article  Google Scholar 

  3. 3

    Crovisier, J. et al. Carbon monoxide emissions at 4.7μm from Venus’ atmosphere. Planet. Space Sci. 54, 1398–1414 (2006)

    ADS  CAS  Article  Google Scholar 

  4. 4

    Lellouch, E. et al. Monitoring of mesospheric structure and dynamics. In Venus II: Geology, Geophysics, Atmosphere, and Solar Wind Environment (eds Bougher, S. W. Hunten, D. M. & Philips R. J.) 295–324 (Univ. Arizona Press, Tucson, 1997)

    Google Scholar 

  5. 5

    Drossart, P. et al. Scientific goals for the observation of Venus by VIRTIS on ESA/Venus Express mission. Planet. Space Sci. 10.1016/j.pss.2007.01.03 (in the press)

  6. 6

    Lopez-Valverde, M. A., Drossart, P., Carlson, R., Mehlman, R. & Roos-Serote, M. Non-LTE infrared observations at Venus: From NIMS/Galileo to VIRTIS/Venus Express. Planet. Space Sci. 10.1016/j.pss.2007.01.008 (in the press). (2007)

  7. 7

    Roldan, C., Lopez-Valverde, M. A., Lopez-Puertas, M. & Edwards, D. P. Non-LTE infrared emissions of CO2 in the atmosphere of Venus. Icarus 147, 11–25 (2000)

    ADS  CAS  Article  Google Scholar 

  8. 8

    Crisp, D. et al. Ground-based near-infrared observations of the Venus nightside: 1.27-μm O2(1Δg) airglow from the upper atmosphere. J. Geophys. Res. 101, 4577–4594 (1996)

    ADS  CAS  Article  Google Scholar 

  9. 9

    Piccioni, G. et al. South-polar features on Venus similar to those near the north pole. Nature 10.1038/nature06209 (this issue).

  10. 10

    Titov, D. V. et al. Venus Express science planning. Planet. Space Sci. 54, 1279–1297 (2006)

    ADS  Article  Google Scholar 

  11. 11

    Lellouch, E. et al. The 2.4–45μm spectrum of Mars observed with the infrared space observatory. Planet. Space Sci. 48, 1393–1405 (2000)

    ADS  CAS  Article  Google Scholar 

  12. 12

    Picard, R. H., Wintersteiner, P. P., Hegblom, E. R. & Richards, E. Remote sensing of discrete stratospheric gravity-wave structure at 4.3-μm from the MSX satellite. Geophys. Res. Lett. 25, 2809–2812 (1998)

    ADS  Article  Google Scholar 

  13. 13

    Formisano, V., Maturilli, A., Giuranna, M., D’Aversa, E. & Lopez-Valverde, M. A. Observations of non-LTE emission at 4–5 microns with the planetary Fourier spectrometer aboard the Mars Express mission. Icarus 182, 51–67 (2006)

    ADS  Article  Google Scholar 

  14. 14

    Lopez-Valverde, M. A. & Lopez-Puertas, M. A non-local thermodynamic equilibrium radiative transfer model for infrared emissions in the atmosphere of Mars. 1. Theoretical basis and nighttime populations of vibrational states. J. Geophys. Res. 99, 13093–13115 (1994)

    ADS  Article  Google Scholar 

  15. 15

    Keating, G. M. et al. Models of Venus neutral upper atmosphere: Structure and composition. Adv. Space Res. 5, 117–171 (1985)

    ADS  CAS  Article  Google Scholar 

  16. 16

    Ohtsuki, S. et al. Ground-based observation of the Venus 1.27-μm O2 airglow. Adv. Space Res. 36, 2038–2042 (2005)

    ADS  Article  Google Scholar 

Download references


We acknowledge the work of the entire Venus Express team of ESA and Astrium, who allowed these data to be obtained. This work is supported by the national space agencies CNES and ASI, and by SFTC in the UK. J.C.G. thanks the FNRS and the PRODEX-ESA program for funding.

Author Contributions P.D. and G.P. have coordinated the work as Principal Investigators of VIRTIS. J.C.G. contributed to the O2 model, L.Z. to the O2 data selection, and M.A.L.-V. to the CO2 model. A.S.-L. and R.H. contributed to the dynamics calculation for Fig. 3. All authors contributed equally to the planning of the work, instrumental calibration and data calibration. F.W.T. and B.B. helped to finalize the paper.

Author information




Corresponding author

Correspondence to P. Drossart.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Drossart, P., Piccioni, G., Gérard, J. et al. A dynamic upper atmosphere of Venus as revealed by VIRTIS on Venus Express. Nature 450, 641–645 (2007). https://doi.org/10.1038/nature06140

Download citation

Further reading


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