OSA's Digital Library

Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 53, Iss. 9 — Mar. 20, 2014
  • pp: 1808–1819

Blue moons and Martian sunsets

Kurt Ehlers, Rajan Chakrabarty, and Hans Moosmüller  »View Author Affiliations

Applied Optics, Vol. 53, Issue 9, pp. 1808-1819 (2014)

View Full Text Article

Enhanced HTML    Acrobat PDF (1462 KB) Open Access

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



The familiar yellow or orange disks of the moon and sun, especially when they are low in the sky, and brilliant red sunsets are a result of the selective extinction (scattering plus absorption) of blue light by atmospheric gas molecules and small aerosols, a phenomenon explainable using the Rayleigh scattering approximation. On rare occasions, dust or smoke aerosols can cause the extinction of red light to exceed that for blue, resulting in the disks of the sun and moon to appear as blue. Unlike Earth, the atmosphere of Mars is dominated by micron-size dust aerosols, and the sky during sunset takes on a bluish glow. Here we investigate the role of dust aerosols in the blue Martian sunsets and the occasional blue moons and suns on Earth. We use the Mie theory and the Debye series to calculate the wavelength-dependent optical properties of dust aerosols most commonly found on Mars. Our findings show that while wavelength selective extinction can cause the sun’s disk to appear blue, the color of the glow surrounding the sun as observed from Mars is due to the dominance of near-forward scattering of blue light by dust particles and cannot be explained by a simple, Rayleigh-like selective extinction explanation.

© 2014 Optical Society of America

OCIS Codes
(010.0010) Atmospheric and oceanic optics : Atmospheric and oceanic optics
(290.0290) Scattering : Scattering
(330.0330) Vision, color, and visual optics : Vision, color, and visual optics

ToC Category:
Atmospheric and Oceanic Optics

Original Manuscript: October 21, 2013
Revised Manuscript: January 9, 2014
Manuscript Accepted: February 10, 2014
Published: March 18, 2014

Kurt Ehlers, Rajan Chakrabarty, and Hans Moosmüller, "Blue moons and Martian sunsets," Appl. Opt. 53, 1808-1819 (2014)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. H. Horvath, G. Metzig, O. Preining, and R. Pueschel, “Observation of a blue sun over New Mexico, U.S.A.,” Atmos. Environ. 28, 621–630 (1994). [CrossRef]
  2. M. Lemmon, M. Wolff, M. Smith, R. Clancy, D. Banfield, G. A. Landis, A. Ghosh, P. H. Smith, N. Spanovich, B. Whitney, P. Whelley, R. Greeley, S. Thompson, J. F. Bell, and S. W. Squyres, “Atmospheric imaging results from the Mars exploration rovers: spirit and opportunity,” Science 306, 1753–1756 (2004). [CrossRef]
  3. G. Mie, “Beiträge Zur Optik trüber Medien, speziell kolloidaler Metallösungen,” Annalen der Physik, Vierte Folge 25, 377–445 (1908).
  4. P. Debye, “Das Elektromagnetische Feld um einen Zylinder und die Theorie des Regenbogens,” Phys. Z. 9, 775–778 (1908).
  5. H. van de Hulst, Light Scattering by Small Particles (Dover, 1981).
  6. M. Tomasko, L. Doose, M. Lemmon, P. Smith, and E. Wegryn, “Properties of dust in the Martian atmosphere from the Imager on Mars Pathfinder,” J. Geophys. Res. 104, 8987–9007 (1999). [CrossRef]
  7. L. Rayleigh, “On the light from the sky, its polarization and color,” Philos. Mag. 41, 107–120, 274–279 (1929).
  8. J. Aitken, “On some phenomena connected with cloudy condensation,” in Collected Scientific Papers of John Aitken, LL.D. F.R.S. (Cambridge, 1923), pp. 279–280.
  9. S. Bishop, “The remarkable sunsets,” Nature 29, 259–260 (1884). [CrossRef]
  10. D. Kim, M. Chin, H. Yu, T. F. Eck, A. Sinyuk, A. Smirnov, and B. N. Holben, “Dust optical properties over North Africa and Arabian Peninsula derived from the AERONET Dataset,” Atmos. Chem. Phys. 11, 10733–10741 (2011). [CrossRef]
  11. J. Durward, “Blue colour of the sun and surrounding sky in a dust storm,” Q. J. R. Meteorol. Soc. 63, 54–64 (1937). [CrossRef]
  12. H. Hogg, “Blue Sun,” JR Astron. Soc. Can. 44, 241–245 (1950).
  13. http://www.jpl.nasa.gov/video/index.php?id=954 .
  14. C. Bohren and D. Huffman, Absorption and Scattering of Light by Small Particles (Wiley, 1998).
  15. P. Bouguer, Essai d’Optique, sur la gradation de la lumiere (Chez Claude Jombert, 1729).
  16. H. Moosmüller and P. Arnott, “Particle optics in the Rayleigh regime,” J. Air Waste Manage. Assoc. 59, 1028–1031 (2009). [CrossRef]
  17. H. Moosmüller, R. Chakrabarty, and W. Arnott, “Aerosol light absorption and its measurement: a review,” J. Quant. Spectrosc. Radiat. Transfer 110, 844–878 (2009). [CrossRef]
  18. M. J. Berg, C. M. Sorensen, and A. Chakrabarti, “Patterns in Mie scattering: evolution when normalized by the Rayleigh cross section,” Appl. Opt. 44, 7487–7493 (2005). [CrossRef]
  19. M. I. Mishchenko, A. A. Lacis, B. E. Carlson, and L. D. Travis, “Nonsphericity of dust-tropospheric aerosols: implications for aerosol remote-sensing and climate modeling,” Geophys. Res. Lett. 22, 1077–1080 (1995). [CrossRef]
  20. M. I. Mishchenko, L. D. Travis, R. A. Kahn, and R. A. West, “Modeling phase functions for dustlike tropospheric aerosols using a shape mixture of randomly oriented polydisperse spheroids,” J. Geophys. Res. 102, 16831–16847 (1997). [CrossRef]
  21. L. P. Mie, plot simulator, www.philiplaven.com/mieplot.htm .
  22. B. van der Pol and H. Bremmer, “The diffraction of electromagnetic waves from an electrical point source round a finite conducting sphere, with applications to radiotelegraphy and the theory of the rainbow,” Philos Mag. 24, 141–176, 825–864 (1937).
  23. H. M. Nussenzveig, “High-frequency scattering by a transparent sphere I. Direct reflection and direct transmission,” J. Math. Phys. 10, 82–124 (1969). [CrossRef]
  24. J. Lock, “Cooperative effects among partial waves in Mie scattering,” J. Opt. Soc. Am. A 5, 2032–2044 (1988). [CrossRef]
  25. E. Hovenac and J. Lock, “Assessing the contributions of surface waves and complex rays to far-field Mie scattering by use of the Debye series,” J. Opt. Soc. Am. A, 9781–795 (1992). [CrossRef]
  26. S. Hill and R. Brenner, “Morphology-dependent resonances,” in Optical Effects Associated with Small Particles, P. Barber and R. Chang, eds. (World Scientific, 1988), pp. 3–61.
  27. G. Lothian, “Blue sun and moon,” Nature 168, 1086–1087 (1951). [CrossRef]
  28. J. Bell, D. Savransky, and M. Wolff, “Chromaticity of the Martian sky as observed by the Mars Exploration Rover Pancam instruments,” J. Geophys. Res. 111, E12S05 (2006).
  29. P. Christensen, R. Morris, M. Lane, J. Bandfield, and M. Malin, “Global mapping of Martian hematite mineral deposits: remnants of water-driven processes on early Mars,” J. Geophys. Res. 106, 873–885 (2001).
  30. M. Querry, “Optical constants,” (U.S. Army Chemical Research and Development Center, 1985).
  31. M. Lane, R. Morris, and P. Christensen, “Spectral behavior of hematite at visible/near infrared and mid-infrared wavelengths,” in The Fifth International Conference on Mars, Pasadena, California, 1999.
  32. V. Hamilton, H. McSween, and B. Hapke, “Mineralogy of Martian atmospheric dust inferred from thermal infrared spectra of aerosols,” J. Geophys. Res. 110, E12006 (2005). [CrossRef]
  33. J. Pollack, D. Colburn, F. Flaser, R. Kahn, C. Carlston, and D. Pidek, “Properties and effects of dust particles suspended in the Martian atmosphere,” J. Geophys. Res., 842929–2945 (1979). [CrossRef]
  34. P. Chýlek, V. Srivastava, R. Pinnick, and R. Wang, “Scattering of electromagnetic waves by composite spherical particles: experiment and effective medium approximations,” Appl. Opt. 27, 2396–2404 (1988). [CrossRef]
  35. J. Hansen and L. Travis, “Light scattering in planetary atmospheres,” Space Sci. Rev. 16, 527–610 (1974). [CrossRef]
  36. H. Moosmüller, J. P. Engelbrecht, M. Skiba, G. Frey, R. K. Chakrabarty, and W. P. Arnott, “Single scattering Albedo of fine mineral dust aerosols controlled by iron concentration,” J. Geophys. Res.117, doi:10.1029/2011JD016909 (2012). [CrossRef]

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited