Number 48 (Story #4), September 19, 1991 by Phillip F. Schewe and Ben Stein TITAN HAS AN ANTI-GREENHOUSE EFFECT , report scientists analyzing Voyager 1 data. Saturn's largest moon has a surface pressure of 1.5 atm.; its atmosphere of nitrogen, methane, and hydrogen gives rise to a greenhouse effect which increases surface temperature by 21 K. But, the Voyager scientists note, a high-altitude haze of organic molecules, absorbent at solar wavelengths but transparent at thermal-infrared wavelengths, has a cooling effect, reducing surface temperatures by an estimated 9 K. (Science, 6 September 1991.)