Solar Physics

, Volume 290, Issue 10, pp 2617–2648 | Cite as

A Novel Technique for Measuring the Solar Radius from Eclipse Light Curves – Results for 2010, 2012, 2013, and 2015

  • Philippe Lamy
  • Jean-Yves Prado
  • Olivier Floyd
  • Patrick Rocher
  • Guillaume Faury
  • Serge Koutchmy
Article

Abstract

We report on a novel technique for measuring the solar radius during total solar eclipses that exploits light curves recorded just before and after second and third contacts. The measurements are performed by pre-programmed photometers that are deployed over the eclipse paths and are operated without supervision. The recorded light curves are compared to synthetic light curves calculated from high-accuracy ephemerides and lunar-limb profiles constructed from the topographic model of the Moon provided by the Kaguya lunar space mission. A minimization process between the two sets of curves yields the solar radius. Altogether, seventeen determinations have been obtained during the past four total eclipses with the following averages (at a wavelength of 540 nm and scaled to 1 AU): \(959.94\pm0.02~\mbox{arcsec}\) on 11 July 2010, \(960.02\pm0.04~\mbox{arcsec}\) on 13 November 2012, \(959.99\pm0.09~\mbox{arcsec}\) on 3 November 2013, and \(960.01\pm0.09~\mbox{arcsec}\) on 20 March 2015. Part of the differences between these four values may be attributed to weather conditions. Averaging the whole set of measurements yields a radius of \(959.99\pm0.06~\mbox{arcsec}\) (\(696{,}246\pm45~\mbox{km}\)), which agrees excellently well with the most recent data and supports an upward revision of the standard IAU value, as previously suggested.

Keywords

Sun Sun: diameter Sun: eclipses 

References

  1. Ajabshirzadeh, A., Koutchmy, S.: 2005, In: Danesy, D., Poedts, S., De Groof, A., Andries, J. (eds.) Proceedings of the 11th European Solar Physics Meeting “The Dynamic Sun: Challenges for Theory and Observations” 600, ESA, Noordwijk. ADS. Google Scholar
  2. Auwers, A.: 1891, Der Sonnendurchmesser und der Venusdurchmesser nach den Beobachtungen an den Heliometern der deutschen Venus-Expeditionen. Astron. Nachr. 128, 361. DOI. ADS. CrossRefADSGoogle Scholar
  3. Bazin, C., Koutchmy, S.: 2013, Helium shells and faint emission lines from slitless flash spectra. J. Advert. Res. 4, 307. DOI. ADS. CrossRefGoogle Scholar
  4. Capitaine, N., Wallace, P.T., Chapront, J.: 2003, Expressions for IAU 2000 precession quantities. Astron. Astrophys. 412, 567. DOI. ADS CrossRefADSGoogle Scholar
  5. Capitaine, N., Wallace, P.T., McCarthy, D.D.: 2003, Expressions to implement the IAU 2000 definition of UT1. Astron. Astrophys. 406, 1135. DOI. ADS. CrossRefADSGoogle Scholar
  6. Djafer, D., Thuillier, G., Sofia, S.: 2008, A comparison among solar diameter measurements carried out from the ground and outside Earth’s atmosphere. Astrophys. J. 676, 651. DOI. ADS. CrossRefADSGoogle Scholar
  7. Dunham, D.W., Thompson, J.R., Herald, D.R., Buechner, R., Fiala, A.D., Warren, W.H. Jr., et al.: 2005, SORCE Science Meeting September 14 and 16, Durango, Colorado (lasp.colorado.edu/sorce/news/2005ScienceMeeting/).
  8. Emilio, M., Leister, N.V.: 2005, Solar diameter measurements at São Paulo Observatory. Mon. Not. Roy. Astron. Soc. 361, 1005. DOI. ADS. CrossRefADSGoogle Scholar
  9. Emilio, M., Kuhn, J.R., Bush, R.I., Scholl, I.F.: 2012, Measuring the solar radius from space during the 2003 and 2006 Mercury transits. Astrophys. J. 750, 135. DOI. ADS. CrossRefADSGoogle Scholar
  10. Fienga, A., Manche, H., Laskar, J., Gastineau, M.: 2008, INPOP06: a new numerical planetary ephemeris. Astron. Astrophys. 477, 315. DOI. ADS. CrossRefADSGoogle Scholar
  11. Fok, H.S., Shum, C.K., Yi, Y., Araki, H., Ping, J., Williams, J.G., et al.: 2011, Accuracy assessment of lunar topography models. Earth Planets Space 63, 15. DOI. ADS. CrossRefADSGoogle Scholar
  12. Hauchecorne, A., Meftah, M., Irbah, A., Couvidat, S., Bush, R., Hochedez, J.-F.: 2014, Solar radius determination from Sodism/Picard and HMI/SDO observations of the decrease of the spectral solar radiance during the 2012 June Venus Transit. Astrophys. J. 783, 127. DOI. ADS. CrossRefADSGoogle Scholar
  13. Herald, D.: 2015, Occultation prediction Software, Occult v4.1.1, IOTA. www.lunar-occultations.com/iota/iotandx.htm.
  14. Hestroffer, D., Magnan, C.: 1998, Wavelength dependency of the Solar limb darkening. Astron. Astrophys. 333, 338. ADS. ADSGoogle Scholar
  15. Kilcik, A., Sigismondi, C., Rozelot, J.P., Guhl, K.: 2009, Solar radius determination from total solar eclipse observations on 29 March 2006. Solar Phys. 257, 237. DOI. ADS. CrossRefADSGoogle Scholar
  16. Kuhn, J.R., Bush, R.I., Emilio, M., Scherrer, P.H.: 2004, On the constancy of the solar diameter. II. Astrophys. J. 613, 1241. ADS. CrossRefADSGoogle Scholar
  17. Makarova, E.A., Kharitonov, A.V.: 1977, Averaged data for the limb darkening of the quiet sun – The integrated spectrum. Soviet Astron. 21, 65. ADS. ADSGoogle Scholar
  18. Meftah, M., Hauchecorne, A., Crepel, M., Irbah, A., Corbard, T., Djafer, D., Hochedez, J.-F.: 2014, The plate scale of the SODISM instrument and the determination of the solar radius at 607.1 nm. Solar Phys. 289, 1. DOI. ADS. CrossRefADSGoogle Scholar
  19. Neckel, H., Labs, D.: 1994, Solar limb darkening 1986 – 1990 (lambda 303 to 1099 nm). Solar Phys. 153, 91. DOI. ADS. CrossRefADSGoogle Scholar
  20. Pierce, A.K., Slaughter, C.D.: 1977, Solar limb darkening. I – At wavelengths of 3033 – 7297. Solar Phys. 51, 25. DOI. ADS. CrossRefADSGoogle Scholar
  21. Raponi, A., Sigismondi, C., Guhl, K., Nugent, R., Tegtmeier, A.: 2012, The measurement of solar diameter and limb darkening function with the eclipse observations. Solar Phys. 278, 269. DOI. ADS. CrossRefADSGoogle Scholar
  22. Ribes, J.C., Nesme-Ribes, E.: 1993, The solar sunspot cycle in the Maunder minimum AD1645 to AD1715. Astron. Astrophys. 76, 549. ADS. ADSGoogle Scholar
  23. Rozelot, J.P., Damiani, C., Lefebvre, S.: 2009a, Variability of the solar shape (before space dedicated missions). J. Atmos. Solar-Terr. Phys. 71, 1683. DOI. ADS. CrossRefADSGoogle Scholar
  24. Rozelot, J.P., Damiani, C., Pireaux, S.: 2009b, Probing the solar surface: The oblateness and astrophysical consequences. Astron. Astrophys. 703, 1791. DOI. ADS. ADSGoogle Scholar
  25. Scholz, M.: 2001, On the interpretation of stellar disc observations in terms of diameters. Mon. Not. Roy. Astron. Soc. 321, 347. DOI. ADS. CrossRefADSGoogle Scholar
  26. Sigismondi, C.: 2009, Guidelines for measuring solar radius with Baily beads analysis. Sci. China Ser. G 52, 1773. DOI. ADS. CrossRefGoogle Scholar
  27. Sigismondi, C., Raponi, A., Bazin, C., Nugent, R.: 2012, Towards a unified definition of solar limb during central eclipses and daily transits. Int. J. Mod. Phys. 12, 405. DOI. ADS. Google Scholar
  28. Steiner, O.: 2005, Radiative properties of magnetic elements II. Center to limb variation of the appearance of photospheric faculae. Astron. Astrophys. 430, 691. DOI. ADS. CrossRefADSGoogle Scholar
  29. Thuillier, G., Sofia, S., Haberreiter, M.: 2005, Past, present and future measurements of the solar diameter. Adv. Space Res. 35, 329. DOI. ADS. CrossRefADSGoogle Scholar
  30. Thuillier, G., Claudel, J., Djafer, D., Haberreiter, M., Mein, N., Melo, S.M.L., et al.: 2011, The shape of the solar limb: Models and observations. Solar Phys. 268, 125. DOI. ADS. CrossRefADSGoogle Scholar
  31. Wittmann, A.: 1977, The diameter of the Sun. Astron. Astrophys. 61, 225. ADS. ADSGoogle Scholar
  32. Wittmann, A.: 1980, The solar limb darkening function at 5012 A and its possible variations. Astron. Astrophys. 83, 312. ADS. ADSGoogle Scholar
  33. Wittmann, A.: 2003, Visual and photoelectric measurements of the solar diameter (1972 – 2002): Methods and results. Astron. Nachr. 324, 378. ADS. CrossRefADSGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  • Philippe Lamy
    • 1
  • Jean-Yves Prado
    • 2
  • Olivier Floyd
    • 3
  • Patrick Rocher
    • 4
  • Guillaume Faury
    • 1
    • 3
  • Serge Koutchmy
    • 5
  1. 1.Laboratoire d’Astrophysique de Marseille, UMR 7236CNRS & Aix-Marseille UniversitéMarseille cedex 13France
  2. 2.Centre National d’Etudes SpatialesToulouseFrance
  3. 3.AKKA Informatique et SystèmesToulouse cedex 1France
  4. 4.Institut de Mécanique Céleste et de Calcul des Ephémérides, UMR 8028CNRS & Observatoire de ParisParisFrance
  5. 5.Institut d’Astrophysique de Paris, UMR 7095CNRS & Université Pierre et Marie CurieParisFrance

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