A brown dwarf star having only 20-50 times the mass of Jupiter is located below and to the left of the bright star GL 229 in this image from the Hubble Space Telescope. At the 19 light year distance to GL 229, the 7.7-arcsec separation between the star and the brown dwarf corresponds to roughly the separation between Pluto and the Sun in our Solar System. The goal of the program described in this report is to detect and characterize Earth-like planets around nearby stars where conditions suitable for life might be found. For a star like the Sun located 30 light years away, the appropriate star-planet separation would be almost 100 times closer than seen here for GL 229B. Elachi, Charles and Angel, Roger and Beichman, Charles A. (Editor) and Boss, Alan and Brown, Robert and Dressler, Alan and Dyson, Freeman and Fanson, James and Ftaclas, Chris and Goad, Lawrence and Klein, Mike and Leger, Alain and Lillie, Charles and Peale, Stanton and Peterson, Deane and Reasenberg, Bob and Sandler, David and Shao, Mike and Simon, Richard and Tenerelli, Domenick Jet Propulsion Laboratory PLANETS; SOLAR SYSTEM; INFRARED INTERFEROMETERS; ASTRONOMICAL INTERFEROMETRY; SPACE EXPLORATION; STAR FORMATION; HUBBLE SPACE TELESCOPE; THERMAL RADIATION; INFRARED SPECTRA; RADIAL VELOCITY; ASTRONOMICAL PHOTOMETRY; SPACE MISSIONS; SPATIAL RESOLUTION; ADAPTIVE OPTICS...

NASA presents information about the astronomy project to map the exploration of nearby planets and orbiting stars. The project consists of a consortium of many institutions to create a space-based optical interferometer, the study of dust clouds around stars, and more. Information about support ground-based programs, supporting space missions, and other details about the project are available.

The question of the existence of other worlds and other living beings has been present in the human quest for knowledge since as far as Epicurus. For centuries this question belonged to the fields of philosophy and theology. The theoretical problem of the formation of the Solar System, and hence of other planetary systems, was tackled only during the 18th century, while the first observational attempts for a detection started less than one hundred years ago. Direct observation of an extra-solar planetary system is an extraordinarily difficult problem: extra-solar planets are at huge distances, are incredibly faint and are overwhelmed by the bright light of their own stars. With virtually no observational insight to test their models, theoreticians have remained for decades in a difficult position to make substantial progress. Yet, the field of stellar formation has provided since the 1980s both the the oretical and observational evidences for the formation of discs at the stage of star birth and for debris materials orbiting the very young stellar systems. It was tempting to consider that these left-overs might indeed later agglomerate into planetary systems more or less similar to ours. Then came observational evidences for planets outside the Solar System.

The past year has produced some of the most exciting results in the history of astronomy, particularly in the area of planets outside our solar system. Only a half-year before our meeting in Toledo, Spain, the first unambiguous detection of planet-sized masses orbiting main sequence stars were reported. Since that time, evidence for a new exo planet has been reported almost at the rate of about once per month. Some of these objects are likely to turn out to be very low-mass stars, but something like half show characteristics - Jupiter-like mass and near-zero orbital eccentricity - which appear to be unique to planets. Almost at the same time that giant planets were being discovered regularly, the two major space agencies, ESA and NASA, have iden tified searches for and detailed study of Earth-like planets as a major priority for the future. In ESA's "Horizon 2000 Plus" programme, an infrared interferometer has been proposed as a possible future Cor nerstone mission. Similarly, scientists in the US produced the "Road Map for the Exploration of Neighboring Planetary Systems (ExNPS)", which provided NASA with a long-term plan which leads also to an infrared interferometer in space to study hypothetical Earth-like worlds beyond our Solar System. Such an observatory is designed to search for the thermal emission from a family of planets, using interferometric nulling to remove the contaminating light from the central star.

Are we alone in the universe? From canals on Mars to the search for ET, the debate goes on. Lucid and accessible, this otherworldly guide chronicles the history of the 20th century obsession with extraterrestrials.