Extraterrestrial astronomy

Radio-astronomy searches (Project Ozma) for communications from intelligent extraterrestrial beings have been carried out at this frequency see Interstellar Communication, A. G. W. Cameron, etL, Benjamin, New York, 1963 Communication With Extraterrestrial Inteltt-genee, C. Sagan, ed. MIT Press, 1973. 

Superherodyne spectrometers are now not common in laboratory microwave experiments, but superheterodyne detection plays a major role in radio astronomy, as we shall see later. The reasons are obvious one cannot modulate the energy levels of extraterrestrial molecules, and a radio telescope collects radiant energy at all frequencies simultaneously. One does not have a primary monochromatic source of radiation, as in laboratory experiments. 

AMANDA has yet to observe an extraterrestrial neutrino source, but she has demonstrated the cost-effectiveness and robustness of the technique. The detector is very versatile it addresses many different neutrino physics subjects and sets the most stringent upper limits on Galactic and extragalactic neutrino fluxes. The improved search for diffuse fluxes, which has ruled out several predictions, along with the extended four-year search for point sources has started to constrain the enormous parameter space that exist in many models of neutrino production. The reported experimental limits on the diffuse neutrino flux are less than an order of magnitude above the Waxman-Bahcall bound ( Waxman and Bahcall, 1999). As more of the data on tape is analyzed, AMANDA sensitivities will continue to improve. This is a very exciting time in neutrino astronomy and we look forward to neutrino astrophysics with next generation of neutrino telescopes. 

The conclusion of the hfe and reason existence out of our planet is known to be hypothetical. These questions were discussed by the thinkers of antique Greece and New Era. Nowadays the problem of extraterrestrial civilizations is developed by special sciences, first of all, astronomy. A characteristic featirre of modem exploring the problem of plirrality (habitability) of cosmic worlds, unlike the post-Copemicus period, is the emergence of special scientific works rather than physiophilosophical ones. It is interesting that this research is focused on the problem of communication... 

Ghyba, Ghristopher. The New Search for Life in the Universe. Astronomy 38, no. 5 (May, 2010) 34-39. A well-illustrated article written for the nonscientist describing the fundamentals of the science of astrobiology and the search for extraterrestrial life. 

The jansky, a unit of radio power flux used in radio astronomy, was named for Karl G. Jansky, who is first credited with discovering extraterrestrial radio signals. 

Shostak, Seth. Listening for a Whisper. Astronomy 32, no. 9 (September, 2004) 34-39. Avery brief overview of how radio telescopes are used in the search for extraterrestrial intelligence. 

Throughout most of history, space was inaccessible to humans. The only way to study extraterrestrial objects was through observation. Astronomy began with these simple observations. In the seventeenth century, people began to use telescopes to view the sky, and physics and chemistry began to be important in interpreting their observations. In the nineteenth century, scientists discovered the existence of cosmic rays and learned the nature of meteorites, but the study of space remained largely limited to observations from the surface of the Earth. 

The somewhat controversial field of the search for extraterrestrial intelligence has been treated in [7.104 7.105]. Radio astronomy tools have been used, but very recently the search has been extended to a search for po ible laser flashes from distant objects. The flrst two space craft to leave the solar system (Pioneer 10 and 11, launched in 1972 and 1973, respectively) carried a plaque with the frequencies of the 14 strongest pulsars, expressed with the hydrogen hfs frequency as a base, and with indications of their relative directions with regard to our solar system, as a sign of our own inteUigence [7.106] ... 

This instrument is presently being built by an international European consortium of scientific institutes, the Max Planck Institute for Astronomy (Heidelberg, Germany), the Astronomical Observatory of Torino (Italy) and the Max Planck-Institute for Extraterrestrial Physics (Munidi, Germany). CONICA has two filter wheels with each 20 filter positions (which can be combined to form numerous filter combinations) and detectors of at least 256 pixels. Detectors, filters and other items can be changed within seconds. Masks, filters, cold stops, grisms, polarization analysers, camera selection and detector selection, all can be chosen independently. 

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