Transit spectroscopy of temperate Jupiters with ARIEL: a feasibility study


Several temperate Jupiters have been discovered to date, but most of them remain to be detected. In this note, we analyse the expected infrared transmission spectrum of a temperate Jupiter, with an equilibrium temperature ranging between 350 and 500 K. We estimate its expected amplitude signal through a primary transit, and we analyse the best conditions for the host star to be filled in order to optimize the S/N ratio of its transmission spectrum. Calculations show that temperate Jupiters around M stars could have an amplitude signal higher than 10−4 in primary transits, with revolution periods of a few tens of days and transit durations of a few hours. In order to enlarge the sampling of exoplanets to be observed with ARIEL (presently focussed on objects warmer than 500 K), such objects could be considered as additional possible targets for the mission.

This is a preview of subscription content, log in to check access.

Fig. 1
Fig. 2.
Fig. 3.
Fig. 4.


  1. 1.

    Bolton, S.J., et al.: Jupiter’s interior and deep atmosphere: the initial pole-to-pole passes with the Juno spacecraft. Science. 356, 6340–6344 (2017)

    Article  Google Scholar 

  2. 2.

    Clanton, C., Gaudi, B.S.: Synthetizing exoplanet demographics from radial velocity and microlensing surveys. II. The frequency of planets orbiting M-dwarfs. Astrophys. J. 791, 91 (2014) (23pp)

    ADS  Article  Google Scholar 

  3. 3.

    Encrenaz, T., et al.: The atmospheric composition and structure of Jupiter and Saturn from ISO observations: what have we learnt? Plan. Space Sci. 47, 1225–1242 (1999)

    ADS  Article  Google Scholar 

  4. 4.

    Gillon, M., et al.: Seven temperate terrestrial planets around the nearby utra-cool dwarf star TRAPPIST-1. Nature. 542, 456–460 (2017)

    ADS  Article  Google Scholar 

  5. 5.

    Grevesse, N., Asplund, M., Sauval, A.J.: The new solar chemical composition. EAS Publ. Ser. 17, 21–30 (2005)

    Article  Google Scholar 

  6. 6.

    Henry, T., Walkowicz, L.M., Barto, T.C., Golimowsky, D.A.: Astron. J. 123, 2002–2009 (2002)

    ADS  Article  Google Scholar 

  7. 7.

    Kasting, J.F., Whitmire, D.P., Reynolds, R.T.: Habitable zones around main-sequence stars. Icarus. 101, 108–128 (1993)

    ADS  Article  Google Scholar 

  8. 8.

    Lainey, V.: Quantification of tidal parameters from solar system data. Celest. Mech. Dyn. Astron. 126, 145–156 (2016)

    ADS  Article  Google Scholar 

  9. 9.

    Léger, A., et al.: Transiting exoplanets from the CoRoT space mission. VIII CoRoT-7 b: the first super-earth with measured radius. Astron. Astrophys. 506, 287–302 (2009)

    ADS  Article  Google Scholar 

  10. 10.

    Morley, C.V., et al.: Neglected clouds in T and Y dwarf atmospheres. Astrophys. J. 756, 172 (2012) (17pp)

    ADS  Article  Google Scholar 

  11. 11.

    Murray, C.D., Dermott, S.F.: Solar system dynamics. Cambride University Press, Cambridge (2000)

    Google Scholar 

  12. 12.

    Owen, T., Encrenaz, T.: Compositional constraints on giant planet formation. Plan. Space Sci. 54, 1188–1196 (2006)

    ADS  Article  Google Scholar 

  13. 13.

    Owen, T., McKellar, A.R.W., Encrenaz, T., et al.: A study of the 1.56-μm band of NH3 on Jupiter and Saturn. Astron. Astrophys. 54, 291–295 (1977) 61, 147-147

    ADS  Google Scholar 

  14. 14.

    Pollack, J.B., et al.: Formation of the giant planets by concurrent accretion of solids and gas. Icarus. 124, 62–85 (1996)

    ADS  Article  Google Scholar 

  15. 15.

    Rajpurohit, A.S., Reylé, C., Allard, F., et al.: Astron. Astrophys. 556, A15 (2013)

    Article  Google Scholar 

  16. 16.

    Reylé, C., Scholz, R. D., Schultheis, M. et al.: Optical spectroscopy of high proper motion stars: new M dwarfs within 10 pc and the closest pair of subdwarfs. Month. Not. R. Astron. Soc. 373, 705–714 (2016)

  17. 17.

    Robin, A., Reylé, C., Luri, X., et al.: Mem. S. A. It. 85, 560 (2014)

    ADS  Google Scholar 

  18. 18.

    Rowe, J.F., Matthews, J.M., Seager, S., et al.: The very low albedo of an extrasolar planet: MOST space-based photometry of HD 209458. Astrophys. J. 689, 1345–1353 (2008)

    ADS  Article  Google Scholar 

  19. 19.

    Schneider, J., Deldieu, C., Le Sidaner, P., et al.: Defining and cataloguing exoplanets: the database. Astron. Astrophys. 532, A79 (2011)

    Article  Google Scholar 

  20. 20.

    Sudarsky, D., Burrows, A., Pinto, P.: Albedos and reflection spectra of extrasolar giant planets. Astrophys. J. 588, 1121–1148 (2000)

    ADS  Article  Google Scholar 

  21. 21.

    Tinetti, G. et al.: The EChO Mission Proposal – a candidate for the ESA M3 mission (2011)

  22. 22.

    Tinetti, G., Encrenaz, T., Coustenis, A.: Spectroscopy of planetary atmospheres in our galaxy. Astron. Astrophys. Rev. 21, 63 (2013)

    ADS  Article  Google Scholar 

  23. 23.

    Tinetti, G. et al.: The ARIEL Mission Proposal – a candidate for the ESA M4 mission (2015)

  24. 24.

    Zingales, T., Tinetti, G., Pillitteri, I. et al.: The ARIEL mission reference sample. Experimental Astronomy (2017, in press)

Download references


We acknowledge support from the French National Research Agency (ANR) project (contract ANR-16-CE31-0005-03). G.T acknowledges support from the ERC Project Exolights (id. 617119).

Author information



Corresponding author

Correspondence to Thérèse Encrenaz.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Encrenaz, T., Tinetti, G. & Coustenis, A. Transit spectroscopy of temperate Jupiters with ARIEL: a feasibility study. Exp Astron 46, 31–44 (2018).

Download citation


  • Exoplanets
  • Transit spectroscopy
  • Infrared spectroscopy