DOI QR코드

DOI QR Code

THE RED COLOR OF MARS FROM OPTICAL SPECTRA

  • Received : 2014.11.30
  • Accepted : 2015.06.30
  • Published : 2015.09.30

Abstract

Colors have been derived from the observed optical spectrum of Mars and Jupiter. It is known that the planets and the Moon emit reflected sunlight and thus their spectra are similar to the spectrum of solar radiation. The question was then why is the color of Mars different from that of other planets, i.e. red, although it would share the same spectrum of reflected sunlight. Can one derive color from the spectrum? Therefore, we observed the optical spectra of the scattered sunlight in day time for the Moon and Mars using a 1-D array spectrograph on the 12-inch reflecting telescope in the Korea Science Academy of KAIST in Busan, Korea. We adopted the International Commission on Illumination (CIE) in 1931 of three spectral sensitivity peaks for the human eye in short, medium and long wavelengths in visible light. The observed spectra were imposed on CIE sensitivities and the color detected by the human eye was derived. The Mars spectrum represents red color and the Moon white. It is a similar color to that which a human would see. This result means that color is easily derived from astronomical spectra. The appearance of the planets surface can be determined for Mars, which is the result of iron oxide.

Keywords

References

  1. Guild, J., 1931, The Colorimetric Properties of the Spectrum, Philosophical Transactions of the Royal Society of London, A230, 149
  2. Harris, A. C. & Weatherall, I. L., 1990, Objective Evaluation of Colour Variation in the Sand-burrowing Beetle Chaerodes Trachyscelides White (Coleoptera: Tenebrion-idae) by Instrumental Determination of CIE LAB Values, Journal of the Royal Society of New Zealand, 20, 3
  3. Smith, V. C. & Pokorny, J., 1975, Spectral Sensitivity of the Foveal Cone Photopigments Between 400 and 500 nm, Vision Research, 15, 161 https://doi.org/10.1016/0042-6989(75)90203-5
  4. Song, I., 2015, Handy Spectrograph and Its Application in Astronomical Education, in this proceeding.