TY - JOUR
AU - Albrecht, Sebastian
AB - Astronomical Society of the Pacific. 87 less, probably, above unit area on Mars than in our atmosphere about the same area of Mount Whitney. It is difficult to understand how so small an amount of water can keep a geometrical canal system on Mars in active operation. March, 1910. ON THE SPECTRUM OF MARS AS PHOTOGRAPHED WITH HIGH DISPERSION. By W. W. Campbell and Sebastian Albrecht. Let us recall that the solar spectrum, as viewed by terres- trial observers, is composite. Photospheric light, in passing out through the gases and vapors of the Sun's atmosphere, is selectively absorbed, with the result that many thousands of lines are introduced into the spectrum. These rays pass down through the Earth's atmosphere to the observer, and the absorption by water vapor and oxygen in the terrestrial atmosphere introduces many hundreds of additional lines, at definite points in the yellow, orange, and red regions. The observed spectrum of the Sun is in reality the spectrum of the Sun plus the spectrum of the Earth. The spectrum of the Moon, so far as our present problem is concerned, is simply this Sun-Earth spectrum. The light from Mars is photospheric light, which passes out through 
TI - ON THE SPECTRUM OF MARS AS PHOTOGRAPHED WITH HIGH DISPERSION
JF - Publications of the Astronomical Society of the Pacific
DO - 10.1086/121980
DA - 1910-04-01
UR - https://www.deepdyve.com/lp/iop-publishing/on-the-spectrum-of-mars-as-photographed-with-high-dispersion-dR21QuNxfG
SP - 87
VL - 22
IS - 131
DP - DeepDyve
ER -