Universo marzo-abril 2023

MARZO-ABRIL 2023 ASTRO PUBLISHING El riesgo de contactar con una ci- vilización peligrosa en varios as- pectos, combinado con las dificul- tades técnicas y la onerosidad de emprender “conversaciones” con otros planetas, es la base de una de las soluciones más clásicas a la paradoja de Fermi: todo el mun- do escucha pero nadie transmite. Este escenario sería probable so- bre todo si el número de civiliza- ciones tecnológicas fuera mínimo, ya que si fueran muy numerosas, es poco probable que todas adop- taran la misma política aislacio- nista. Aunque nos situemos en el te- rreno de la especulación, según los conocimientos actuales el es- cenario que prevé una marcada rareza de civilizaciones tecnológi- cas parece el más razonable, así como el más tranquilizador para nosotros que apenas nos asoma- mos ahora a la galaxia. De ser así, nuestras débiles señales electro- magnéticas no tienen casi nin- guna posibilidad de llegar a un aparato receptor extraterrestre. La cuestión no es sólo un ejercicio mental o, a lo sumo, una diserta- ción filosófica. Dependiendo de cómo se evalúen las probabilida- des de un contacto, la propen- sión a financiar programas SETI cambia considerablemente. To- memos el ejemplo más sensacio- nal, Breakthrough Listen, puesto en marcha en enero de 2016 por el multimillonario ruso-israelí Yuri Milner con 100 millones de dóla- res a repartir en 10 años. Se trata de un programa que pretende buscar cualquier señal de radio y láser procedente del millón de es- trellas más cercanas y de las 100 galaxias más próximas. Las obser- vaciones finalizarán en 2026, y es demasiado fácil apostar por el re- sultado negativo de esta inicia- tiva: no parece haber ninguna razón válida para que alguien to- ET, are you out there? — The question of intelligent life on other worlds Is there anybody out there? Are other intelligent life forms lurking in outer space – or are they already here? This calm, intelligent and witty survey of the history of humankind’s search for extraterrestrial life brilliantly outlines the historical, fictional, speculative and emerging scientific opinions on what alien life might be like. The fast-moving narrative examines facts, dispels myths and focuses on the possibilities lurking in space. In a popular and easy-to-read style, the author uses cu- rrent research to speculate what life is like on exoplanets, how we might communicate with it, and what Earth might seem like to visitors. Is anybody out there? Are we alone? Or is the universe teeming with intelligent life? Can we expect extraterrestrial civilizations to be common? Oc- casional? Rare? In this wide-ranging Assessment, historian/writer W. H. Collier explores the probabilities of the existence of extra- terrestrial, technological life based on the latest scientific find- ings. Collier undertakes a thorough analysis of just what it would take for technological societies to arise on other planets. From quantifying the number of habitable planets, to examining the genesis and development of life on this planet, to grappling with the emergence of intelligence in our own species, Collier leaves no stone unturned. Are we alone? — Humankind’s search for extraterrestrial civilizations Earth revolves around one of billions of stars in the Milky Way, which is but one of billions of galaxies in the known universe. With odds like this, it seems likely that humankind is not alone. The cutting edge of science promises to provide clues to a de- finitive answer, and steady progress is being made by some of the world’s brightest minds. Are We Alone? is a book for the curious that explores complex concepts in an accessible man- ner. From single-celled organisms to the superintelligent beings of science fiction lore, Are We Alone? examines the intriguing forms that life could take and the conditions required for it to exist beyond earthly confines. First contact — Scientific breakthroughs in the hunt for life beyond Earth Science reporter Marc Kaufman takes readers around the globe, into space, and miles below Earth’s surface to show how the search for life on other planets is changing the way humans think about their own history, about what it means to be human, and about what, exactly, life is. First Contact is the first book to bring together recent developments across many com- peting branches of science, from microbiology to geochemistry, physics, and astronomy, all racing to verify what was once deemed impossible. Kaufman demystifies the key points behind the rigorous science and advanced technology that is edging ever closer to the most important discovery of modern times.