The Hubble Space Telescope (HST) has operated continuously since 1990. During that time, four space shuttle-based service missions were launched, three of which added major observational capabilities. A fifth â€" SM-4 â€" was intended to replace key telescope systems and install two new instruments. The loss of the space shuttle Columbia, however, resulted in a decision by NASA not to pursue the SM-4 mission leading to a likely end of Hubble's useful life in 2007-2008. This situation resulted in an unprecedented outcry from scientists and the public. As a result, NASA began to explore and develop a robotic servicing mission; and Congress directed NASA to request a study from the National Research Council (NRC) of the robotic and shuttle servicing options for extending the life of Hubble. This report presents an assessment of those two options. It provides an examination of the contributions made by Hubble and those likely as the result of a servicing mission, and a comparative analysis of the potential risk of the two options for servicing Hubble. The study concludes that the Shuttle option would be the most effective one for prolonging Hubble's productive life.

Some vols. include supplemental journals of "such proceedings of the sessions, as, during the time they were depending, were ordered to be kept secret, and respecting which the injunction of secrecy was afterwards taken off by the order of the House".

The search for life in the solar system and beyond has to date been governed by a model based on what we know about life on Earth (terran life). Most of NASA's mission planning is focused on locations where liquid water is possible and emphasizes searches for structures that resemble cells in terran organisms. It is possible, however, that life exists that is based on chemical reactions that do not involve carbon compounds, that occurs in solvents other than water, or that involves oxidation-reduction reactions without oxygen gas. To assist NASA incorporate this possibility in its efforts to search for life, the NRC was asked to carry out a study to evaluate whether nonstandard biochemistry might support life in solar system and conceivable extrasolar environments, and to define areas to guide research in this area. This book presents an exploration of a limited set of hypothetical chemistries of life, a review of current knowledge concerning key questions or hypotheses about nonterran life, and suggestions for future research.

The Hubble Space Telescope has produced the most stunning images of the cosmos humanity has ever seen. It has transformed our understanding of the universe around us, revealing new information about its age and evolution, the life cycle of stars, and the very existence of black holes, among other startling discoveries. But it took an amazing amount of work and perseverance to get the first space telescope up and running. The Universe in a Mirror tells the story of this telescope and the visionaries responsible for its extraordinary accomplishments. Robert Zimmerman takes readers behind the scenes of one of the most ambitious scientific instruments ever sent into space. After World War II, astronomer Lyman Spitzer and a handful of scientists waged a fifty-year struggle to build the first space telescope capable of seeing beyond Earth's atmospheric veil. Zimmerman shows how many of the telescope's advocates sacrificed careers and family to get it launched, and how others devoted their lives to Hubble only to have their hopes and reputations shattered when its mirror was found to be flawed. This is the story of an idea that would not die--and of the dauntless human spirit. Illustrated with striking color images, The Universe in a Mirror describes the heated battles between scientists and bureaucrats, the perseverance of astronauts to repair and maintain the telescope, and much more. Hubble, and the men and women behind it, opened a rare window onto the universe, dazzling humanity with sights never before seen. This book tells their remarkable story. A new afterword updates the reader on the May 2009 Hubble service mission and looks to the future of astronomy, including the prospect of a new space telescope to replace Hubble.