Life on the Surface of Venus?

  title={Life on the Surface of Venus?},
  author={C. Sagan},
IT is said (for example, refs. 1–3) that our knowledge of the surface of the cloud covered planet Venus is extremely fragmentary and ambiguous; that there are alternative non-thermal explanations of the microwave emission; that, even if the surface is hot, the polar regions may be cold enough to support life, or sufficiently high mountains may exist, and so on. It seems appropriate to relate some of this speculation to continuing work on the physical environment of Venus. 
Ice Caps on Venus?
The data on Venus obtained by Mariner V and Venera 4 are interpreted as evidence of giant polar ice caps holding the water that must have come out of the volcanoes with the observed carbon dioxide,Expand
Infrared spectra of Venus
A historical account of observations of Venus and their interpretation is given. The major constituent of the atmosphere on Venus (CO2) was detected spectroscopically forty years ago, and minorExpand
The Trouble with Venus
Venus is the closest planet. Its surface has never been seen at optical frequencies; nevertheless we now know with at least fair reliability, and in some cases with remarkable accuracy, its surfaceExpand
Venus, an Astrobiology Target.
The proximity of Venus to Earth, guidance for exoplanet habitability investigations, and access to the potential cloud habitable layer and surface for prolonged in situ extended measurements together make the planet a very attractive target for near term astrobiological exploration. Expand
The Coming Search for Life on Mars
According to modern astronomy, planetary systems and the conditions suitable for life are considered to be of common occurrence in the universe, and the planet Mars is of special interest, and its physical parameters do not exclude the possibility that microorganisms may exist on that planet. Expand
Habitability of the Solar System
After Miller (1953) tested the idea of Urey (1952) about the synthesis of prebiotic molecules from inorganic compounds such as methane, water, and hydrogen, it was clear that abiotic matter couldExpand
Life on the Edge and Astrobiology: Who Is Who in the Polyextremophiles World?
Life exists in almost every ecological niche on Earth, and the majority of living organisms thrive in “normal” or “common” conditions. These are the environments that we are familiar with from ourExpand
Can the biogenicity of Europa's surfical sulfur be tested simultaneously with penetrators and ion traps?
(1) The Abdus Salam ICTP, Applied Physics Scientific Section, Trieste, Italy (, +390-40-22 41 63), (2) Institutode Estudios Avanzados, Caracas 1015A, Republica Bolivariana de Venezuela.,Expand
Vegetative life on Venus? Or investigations with algae which grow under pure CO2 in hot acid media at elevated pressures
Algae grown in pure CO2 under pressure with an acidic nutrient medium at elevated temperatures and one species found in hot-springs was observed to grow, suggesting that if the planet Venus has acidic polar seas, they may harbor photosynthetic life. Expand
Detection of simplest amino acid glycine in the atmosphere of the Venus
Amino acids are considered to be prime ingredients in chemistry, leading to life. Glycine is the simplest amino acid and most commonly found in animal proteins. It is a glucogenic and non-essentialExpand


Life in the Clouds of Venus?
WHILE the surface conditions of Venus make the hypothesis of life there implausible, the clouds of Venus are a different story altogether. As was pointed out some years ago1, water, carbon dioxideExpand
Radio observations of Venus and the interpretations
The radio observations of Venus are reviewed and compared with theoretical microwave spectra computed for a variety of models of the Venusian environment. The models considered are (a) a CO2-N2Expand
Structure of the lower atmosphere of Venus
Abstract If the centimeter microwave emission from Venus arises from its surface, the radar reflectivities and microwave brightness temperatures give mean darkside surface temperatures of about 640°Expand
Abstract : Measurements of the brightness distribution and differential polarization over the surface of the planet Venus have been made at a wavelength of 10.6 cm with two element interferometersExpand
The microwave phase effect of Venus
The disk-integrated brightness temperature of Venus between 8 mm and 10 cm has been observed to vary with phase angle, the lowest temperature occuring just after inferior conjuction. We apply theExpand
The ionospheric model of the Venus microwave emission: An obituary
Abstract In the ionospheric model of Venus, the observed microwave radiation is attributed to free-free emission of electrons in a dense Cytherean ionosphere. The present paper discusses theExpand
Anisotropic nonconservative scattering and the clouds of Venus
Expressions have been obtained in a modified Schuster-Schwarzschild approximation describing the monochromatic transmissivity, reflectivity, and absorptivity of a cloud layer characterized by anExpand
Microwave Absorption in Models of the Atmosphere of Venus.
  • W. Ho
  • Geology, Chemistry
  • 1966
Coefficients of induced absorption in model atmospheres contaming CO2, N2, A, and Ne, needed to calculate the properties of the lower atmosphere of Venus from the radio observations on the assumptionExpand
An analysis of the Mariner 2 microwave observations of Venus
Mariner 2 limb darkening measurements of Venus at microwave range, discussing peak brightness temperature and opacity models