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Detection of Extraterrestrial Life. Method II- Optical Rotatory Dispersion

The object of this study is to develop polarimetric methods to detect the presence of DNA (deoxyribonucleic acid) or its congeners in soil suspensions, and through these methods determine the existence of life (as known terrestrially) on other planets. The cotton region associated with optically active organic compounds is being used to detect and characterize the compounds above. An apparatus has been designed and assembled which can measure optical rotations in systems which strongly attenuate incident-polarized, monochromatic light. This instrument was used to measure the optical rotatory dispersion spectra of nucleosides, a polynucleotide, and proteins whose optical density at 260 microns approached 1.0. This work is discussed in the final report on Contract NASR-85, Detection of Extraterrestrial Life, Method II: Optical Rotatory Dispersion. Recent work in Melpar laboratories has reaffirmed these rotatory dispersion spectra. Based upon the analysis of the optical components associated with this apparatus, however, these measurements must be considered as qualitative rather than quantitative. The reason for this is discussed in greater detail subsequently in this report. In addition, an evaluation of the theoretical and instrumental aspects of making rotatory-dispersion measurements in the cotton region has resulted in a procedure for measuring optical rotation.

LIFE DETECTOR↗

The search for extraterrestrial life.

Approaches for analyzing possible life forms on other planets, noting detection of microorganisms or enzymes, radio contact and retracing life in laboratory

LIFE DETECTOR↗

The search for extraterrestrial life: Recent developments; Proceedings of the Symposium, Boston University, MA, June 18-21, 1984

The conference presents papers on the history of the search for extraterrestrial life, the scientific rationale and methods used in the search for other planetary systems, the detection of distant planets with the Space Telescope, planetary searches using optical astrometric interferometers, and infrared spectral identification of complex organic molecules in interstellar grains. Also considered are universal protein ancestors from hydrogen cyanide and water, astronomical sources of polarized light and their role in determining molecular chirality on earth, the universal diagrams and life in the universe, the precambrian evolution of terrestrial life and a thermodynamic approach to the occurrance and appearance of galactic life forms. Papers are also presented on the Ohio Seti program, lunar reflections of terrestrial radio leakage, the multichannel spectrum analyzer, software implementation of detection algorithms for the MCSA, the Serendip II design, galactic colonization and competition in a young galactic disk, implications of ancient and future migrations, extraterrestrial intelligence, the ineviability and the possible structures of supercivilizations, planetary, interplanetary and interstellar organic matter, and universal aspects of biological evolution.

Papagiannis, M. D.↗

Extraterrestrial Life: Life on Mars - Then and Now

The recent claim to have identified possible signs of ancient life on Mars has been widely publicized and discussed. The authors conceded that none of the half-dozen pieces of evidence adduced in their paper individually provided strong support for extraterrestrial life, though they argued that the pieces added up to a case worth considering. Most - perhaps all - of the observed phenomena have counterparts in the inorganic world, so even the combination does not make a compelling case that there was ever life on Mars. Nevertheless, the importance of the problem has justified bringing the results to general attention. The paper has focussed interest on the origin and possible ubiquity of life, and on how we can design techniques capable of giving a more definitive answer to the question of whether there is, or has ever been, life elsewhere in the Universe.

Arrhenius, Gustaf↗

Reconsidering the Theological and Ethical Implications of Extraterrestrial Life

As we stand on the threshold of a new millennium, we also find ourselves at the brink of a new and exciting era in space exploration. In fact, this new era has already begun, with the successful landing and exploration of Mars by the Pathfinder mission in July 1997. Pathfinder represents an important scientific accomplishment for NASA because it demonstrated the agency's ability to successfully explore space at a relatively modest price. At the same time, Pathfinder revealed once again the genuine interest and fascination that people all over planet Earth have for space exploration. The recent Pathfinder mission to Mars was only the first in an ambitious series of NASA missions planned for exploration of Mars, Earth's nearest planetary neighbor where extraterrestrial life is a real possibility. In March 1998, the next step in this exploration takes place, when the Mars Global Surveyor--which is already in orbit around Mars--begins photographing and mapping the Martian surface. NASA plans to continue its exploration with additional landers and orbiters taking off for Mars every 26 months, when the paths of Mars and Earth bring them in closer proximity. By the year 2005, NASA hopes to launch a mission that will return martian samples to Earth. And, as early as 2011, astronauts could be rocketing from Earth for the first human landing on the Red Planet. In the distant future, there may be even more grandiose plans, including the possibility of engineering an atmosphere on Mars that could support biological life.

Randolph, Richard O.↗

Reconsidering the Theological and Ethical Implications of Extraterrestrial Life

As we stand on the threshold of a new millennium, we also find ourselves at the brink of a new and exciting era in space exploration. In fact, this new era has already begun, with the successful landing and exploration of Mars by the Pathfinder mission in July 1997. Pathfinder represents an important scientific accomplishment for NASA because it demonstrated the agency's ability to successfully explore space at a relatively modest price. At the same time, Pathfinder revealed once again the genuine interest and fascination that people all over planet Earth have for space exploration. The Pathfinder mission is just one of several recent events-both scientific and cultural-that reveal this deep and almost unquenchable curiosity about space-and the possibility that there is life "out there." In August 1996, the public was captivated with NASA's announcement that a meteorite from Mars may contain evidence of early microscopic life. Shortly after the NASA announcement, media coverage of the discovery-and public discourse concerning the discovery-turned to an examination of the theological implications of evidence for extraterrestrial, albeit unintelligent, life. To a lesser extent, public reaction to the Hale-Bopp comet in the Spring of 1996 is also suggestive of many persons' deep passion to know more about space.

Randolph, Richard O.↗

Potential targets in the search for extraterrestrial life.

Discussion of the potential for increasing understanding of the origins of terrestrial life by examination of other planets. If living organisms should be found on another planet, they could only have been transported from an inhabited planet or originated independently. The fundamental chemical and structural attributes of terrestrial organisms are so remarkably uniform that any living forms outside the terrestrial blueprint would almost certainly be regarded as alien organisms. It has been shown experimentally by various investigators that life can exist in an extremely wide range of temperatures and pressures. The presence of an atmosphere appears to be necessary.

Klein, H. P.↗