{"id":19063,"date":"2025-08-02T16:41:34","date_gmt":"2025-08-02T14:41:34","guid":{"rendered":"https:\/\/www.oavda.it\/uncategorized\/astronomia-da-fantascienza-8"},"modified":"2026-05-18T15:40:36","modified_gmt":"2026-05-18T13:40:36","slug":"astronomia-da-fantascienza-8","status":"publish","type":"post","link":"https:\/\/www.oavda.it\/en\/news-en\/astronomia-da-fantascienza-8","title":{"rendered":"Astronomia da fantascienza \ud83d\udc49 -8"},"content":{"rendered":"<h3><span style=\"color: #ffcc00\">*Sci-fi Astronomy, edited by Camilla Pianta*<\/span><\/h3>\n<h2><span style=\"color: #ffcc00\"><b><em>Diaspora<\/em>, the twilight of Earth in the echo of gravitational waves \ud83d\udcab<\/b><\/span><b><\/b><\/h2>\n<h3><em><span style=\"color: #ffcc00\"><b>What if a neutron star collision happened in our galactic backyard?<\/b><\/span><\/em><\/h3>\n<h3><span style=\"color: #c0c0c0\"><strong>COUNTDOWN TO APRIL 2026, THE CENTENARY OF SCIENCE FICTION: -8<\/strong><\/span><\/h3>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/0\/03\/Flag_of_Italy.svg\/960px-Flag_of_Italy.svg.png\" alt=\"File:Flag of Italy.svg\" width=\"20\" height=\"13\" \/>\u00a0 <em><a href=\"https:\/\/www.oavda.it\/editoriale\/centenario-della-fantascienza\">Clicca qui<\/a> per la versione italiana di questo articolo<\/em><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-weight: 400\">By one o\u2019clock in the afternoon, the gravitational waves from Lacerta had intensified to a hundred times their usual strength. There was no need to wait for the final data from the outermost TERAGO detectors to filter out interference: the signal was arriving directly from the Bullialdus crater in real time. The pulse from Lac G-1, accelerating steadily, was now strong enough to overwhelm every other celestial source of gravitation. The waves were visibly shortening \u2014 each cycle becoming narrower than the last \u2014 and the two most recent peaks were separated by only fifteen minutes, a clear indication that the neutron stars had already crossed the two-hundred-thousand-kilometre threshold. Within an hour, the distance between them would be halved; a few minutes later, it would vanish entirely. Yatima had hoped that the system\u2019s evolution might slow, but the gleisners\u2019 extrapolations, growing ever steeper, proved accurate.<\/span><span style=\"font-weight: 400\"><br \/>\n<\/span><span style=\"font-weight: 400\"><br \/>\n<\/span><i><span style=\"font-weight: 400\">Diaspora<\/span><\/i><span style=\"font-weight: 400\"> by the Australian writer <span style=\"color: #99ccff\"><strong>Greg Egan<\/strong><\/span> is one of the most ambitious and radical novels of hard science fiction, a narrative that combines scientific rigour and philosophical speculation in a complex post-human future. Egan imagines a humanity fragmented into three distinct evolutionary strands: the <\/span><i><span style=\"font-weight: 400\">statics<\/span><\/i><span style=\"font-weight: 400\">, beings still bound to traditional biological bodies; the <\/span><i><span style=\"font-weight: 400\">gleisners<\/span><\/i><span style=\"font-weight: 400\">, minds transferred into mobile robotic bodies; and the <\/span><i><span style=\"font-weight: 400\">polises<\/span><\/i><span style=\"font-weight: 400\">, virtual cities that host disembodied intelligences such as Yatima, the protagonist \u2014 an artificial consciousness emerging from stochastic mutations in a pre-existing digital genotype. For the inhabitants of the <\/span><i><span style=\"font-weight: 400\">polises<\/span><\/i><span style=\"font-weight: 400\">, science is an immersive, first-hand experience, because they literally enter the mathematical models they construct, perceiving spacetime and extra dimensions as though they were real landscapes. In this way, knowledge of the universe becomes an integral part of their identity.<\/span><\/p>\n<p><span style=\"font-weight: 400\">However, the estimates produced by artificial intelligences, based on an incomplete understanding of gravitational mechanisms in extreme regimes, prove tragically wrong when, in 2996, a catastrophic and unexpected event devastates the Earth: the binary neutron-star system Lac G-1, located about one hundred light-years away, collapses into a single hypermassive star one million years earlier than predicted. Accompanying the merger is the release of a gamma-ray burst powerful enough to strip the ozone from the stratosphere and ravage the entire terrestrial ecosystem, marking the onset of an unprecedented crisis. TERAGO, the lunar observatory designed to detect gravitational waves with the highest possible precision, manages to record the event in real time, but still too late to allow intervention or preparation. Egan writes that, in the coalescence phase of the two neutron stars, gravitational waves of increasing frequency and intensity are emitted, reaching peak at the moment of merger in line with the findings of actual operational detectors \u2014 such as LIGO, Virgo and KAGRA<\/span><span style=\"font-weight: 400\">.<\/span><\/p>\n<figure id=\"attachment_17398\" aria-describedby=\"caption-attachment-17398\" style=\"width: 764px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/diaspora-ega-urania-2003-anobii.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-17398\" src=\"https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/diaspora-ega-urania-2003-anobii.jpg\" alt=\"\" width=\"764\" height=\"400\" srcset=\"https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/diaspora-ega-urania-2003-anobii.jpg 1200w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/diaspora-ega-urania-2003-anobii-300x157.jpg 300w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/diaspora-ega-urania-2003-anobii-1024x536.jpg 1024w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/diaspora-ega-urania-2003-anobii-768x402.jpg 768w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/diaspora-ega-urania-2003-anobii-24x13.jpg 24w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/diaspora-ega-urania-2003-anobii-36x19.jpg 36w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/diaspora-ega-urania-2003-anobii-48x25.jpg 48w\" sizes=\"auto, (max-width: 764px) 100vw, 764px\" \/><\/a><figcaption id=\"caption-attachment-17398\" class=\"wp-caption-text\">The cover art for the Italian edition of <i data-path-to-node=\"4,0\" data-index-in-node=\"42\">Diaspora<\/i> by Greg Egan was created by Franco Brambilla, one of the contemporary masters in this field. Source: <a href=\"https:\/\/www.anobii.com\/it\/books\/diaspora\/018ab2669a64c840d7\">https:\/\/www.anobii.com\/it\/books\/diaspora\/018ab2669a64c840d7<\/a><\/figcaption><\/figure>\n<p><span style=\"font-weight: 400\">According to <strong><span style=\"color: #99ccff\">Albert Einstein<\/span><\/strong>\u2019s general theory of relativity, gravitational waves are ripples in spacetime \u2014 the fabric that permeates the universe and can be deformed under the influence of mass and energy \u2014, perturbations that travel at the speed of light, compressing and stretching spacetime as they pass. They are produced by the merger of compact (enormously massive) objects, such as neutron stars or black holes, in tight binary systems (systems in which the separation between the two components is very small). For a binary system of compact objects to emit gravitational waves, its overall mass distribution must be asymmetric, the total moment of inertia must not be conserved, and the rotational motion of its components must be accelerated. In practical terms, the two bodies must rotate in a manner that is not perfectly symmetric with respect to their common centre of mass, with motion that accelerates and continually alters the mass distribution within the system.<\/span><\/p>\n<p><span style=\"font-weight: 400\">The evolution of a compact binary system can ideally be divided into three phases: inspiral, merger and ringdown. During the inspiral phase, the two components slowly spiral towards one another as they lose energy in the form of gravitational waves. This process causes a gradual orbital decay: the orbit shrinks, the orbital velocity increases, and so do the frequency and amplitude of the gravitational signal. The typical emission frequency ranges from a few tens to a few hundreds of hertz, and its exact value depends on the orbital frequency of the binary system \u2014 that is, how quickly the two objects orbit around the centre of mass: the closer and faster they are, the greater the higher the oscillation rate. The gravitational signal therefore acquires a characteristic profile known as a <\/span><i><span style=\"font-weight: 400\">chirp<\/span><\/i><span style=\"font-weight: 400\">, since the resulting sound exhibits the rising frequency typical of a chirping noise. For the mathematical description of the inspiral phase, post-Newtonian approximations are employed: a series of corrections to the equations of classical physics that progressively introduce relativistic effects into the system\u2019s dynamics.<\/span><\/p>\n<p><span style=\"font-weight: 400\">The situation changes dramatically during the merger phase, when the two bodies come into contact and then coalesce: this is a strongly non-linear regime in which post-Newtonian approximations fail, and Einstein\u2019s field equations must be solved numerically through hydrodynamical simulations. This stage represemts the point of maximum gravitational-wave emission, with the signal attaining its peak amplitude exactly as Egan predicted. Notably, the matter ejected following the merger of neutron stars undergoes the r-process (rapid neutron capture), promoting the synthesis of heavy elements such as gold, platinum and uranium. The radioactive decay of the nuclei of these elements initiate a <\/span><i><span style=\"font-weight: 400\">kilonova<\/span><\/i><span style=\"font-weight: 400\">, a thermal glow visible in the infrared and optical bands. Other electromagnetic phenomena associated with the merger of binary neutron stars, induced by the amplification of their magnetic fields to intensities of the order of 10<sup>16<\/sup>-10<sup>17 <\/sup>Gauss, include relativistic jets and short gamma-ray bursts<\/span><span style=\"font-weight: 400\">.<\/span><\/p>\n<figure id=\"attachment_17450\" aria-describedby=\"caption-attachment-17450\" style=\"width: 800px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/e29_2.png\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-17450\" src=\"https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/e29_2.png\" alt=\"\" width=\"800\" height=\"439\" srcset=\"https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/e29_2.png 800w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/e29_2-300x165.png 300w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/e29_2-768x421.png 768w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/e29_2-24x13.png 24w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/e29_2-36x20.png 36w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/e29_2-48x26.png 48w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><\/a><figcaption id=\"caption-attachment-17450\" class=\"wp-caption-text\">A typical gravitational wave signal produced by a merging black hole binary. The inspiral phase can be described by a post-Newtonian series expansion, while the final part of the ringdown phase can be described using linear perturbation theory (the blue parts of the signal). The merger and the initial ringdown, however, exhibit non-linear spacetime dynamics (the orange part of the signal). Credit: Top, Kip Thorne; bottom, B. P. Abbott et al. (LIGO Scientific Collaboration and Virgo Collaboration), \u201cObservation of gravitational waves from a binary black hole merger\u201d, <em>Phys. Rev. Lett.<\/em> 116, 061102 (2016); adapted by APS\/Carin Cain. Source: <a class=\"ng-star-inserted\" href=\"https:\/\/physics.aps.org\/articles\/v16\/29\" target=\"_blank\" rel=\"noopener\" data-hveid=\"0\" data-ved=\"0CAAQ_4QMahgKEwiP3dLGvsKUAxUAAAAAHQAAAAAQ3QE\">https:\/\/physics.aps.org\/articles\/v16\/29<\/a><\/figcaption><\/figure>\n<p><span style=\"font-weight: 400\">Depending on the total mass and the type of stars in the system, the outcome of the merger may be either a black hole surrounded by a hot, dense accretion disc, or a hypermassive and unstable neutron star, which may collapse into a black hole after a few milliseconds or persist for longer, while still emitting gravitational waves at an almost constant frequency. Specifically, if the sum of the masses of the two neutron stars exceeds the critical threshold of approximately 2.5\u20133 solar masses \u2014 considering that the mass of a single neutron star lies between 1.2 and 2.3 solar masses \u2014, the formation of a black hole is inevitable, and the system enters the ringdown phase, dominated by quasi-normal modes (a set of exponentially decaying oscillations characteristic of the newly formed black hole).<\/span><\/p>\n<p><span style=\"font-weight: 400\">The gravitational waves radiated during all these phases contain valuable information about the physical parameters of the objects involved, including mass, spin (intrinsic angular momentum), distance, orbital inclination, and, in the case of neutron stars, even their internal structure.<\/span><\/p>\n<p><span style=\"font-weight: 400\">The detection of gravitational signals entails substantial technical difficulties. To this end, interferometers such as LIGO (Laser Interferometer Gravitational-Wave Observatory), Virgo and KAGRA (Kamioka Gravitational Wave Detector) make use of laser beams that travel along two perpendicular arms extending for several kilometres. Gravitational waves imperceptibly alter the lengths of these arms, changing the phase difference between the two beams. These variations are of the order of <\/span><i><span style=\"font-weight: 400\">10<\/span><\/i><i><span style=\"font-weight: 400\">-21<\/span><\/i> <span style=\"font-weight: 400\">m and require seismic isolation, thermal control and ultra-high vacuum conditions for accurate measurement, without interference from background noise. LIGO, with two twin facilities located in the United States \u2014 Livingston, Louisiana, and Hanford, Washington \u2014, has conducted three observing runs: O1 (September 2015 \u2013 January 2016), O2 (November 2016 \u2013 August 2017) and O3 (April 2019 \u2013 March 2020). From the O2 run onwards, LIGO operated in synergy with Virgo, the European interferometer situated near Pisa. This collaboration improved localisation of gravitational-wave sources via triangulation of signals recorded simultaneously at multiple points on Earth.<\/span><\/p>\n<p><span style=\"font-weight: 400\">The first direct detection of gravitational waves came in September 2015, coinciding with the start of the O1 run. The event, GW150914, saw two black holes of roughly 36 and 29 solar masses merge to form a final black hole of about 62 solar masses. In August 2017, close to the end of the O2 run, LIGO and Virgo recorded GW170817, the first observed merger of two neutron stars. Initially spotted through gravitational waves, the event was soon associated with the short gamma-ray burst GRB 170817 and\u00a0 with electromagnetic signals across the entire spectrum, from X-rays to radio waves, thus inaugurating the era of multi-messenger astronomy.<\/span><\/p>\n<p><span style=\"font-weight: 400\">In 2020, the activation of the Japanese interferometer KAGRA, built in an underground laboratory in the Kamioka district and equipped with cryogenically cooled mirrors, provided significant support to the O3 run. The LIGO\u2013Virgo\u2013KAGRA network was therefore able to identify a large number of compact-object mergers with great reliability.<\/span><\/p>\n<figure id=\"attachment_17401\" aria-describedby=\"caption-attachment-17401\" style=\"width: 600px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-17401\" src=\"https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1.jpg\" alt=\"\" width=\"600\" height=\"600\" srcset=\"https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1.jpg 1536w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1-300x300.jpg 300w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1-1024x1024.jpg 1024w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1-150x150.jpg 150w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1-768x768.jpg 768w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1-316x316.jpg 316w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1-511x511.jpg 511w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1-24x24.jpg 24w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1-36x36.jpg 36w, https:\/\/www.oavda.it\/wp-content\/uploads\/2025\/08\/LIGO-KAGRA-VIRGO-Facilities-NW-1536x1536-1-1536x1536-1-48x48.jpg 48w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/a><figcaption id=\"caption-attachment-17401\" class=\"wp-caption-text\">The gravitational wave detectors of the LVK collaboration. From top left, clockwise: LIGO (Hanford); KAGRA; LIGO (Livingston); Virgo. Source: <a class=\"ng-star-inserted\" href=\"https:\/\/www.ego-gw.it\/blog\/2023\/05\/24\/i-rivelatori-di-onde-gravitazionali-stanno-iniziando-un-nuovo-periodo-osservativo-in-cui-esploreranno-i-segreti-delluniverso\/\" target=\"_blank\" rel=\"noopener\" data-hveid=\"0\" data-ved=\"0CAAQ_4QMahgKEwiP3dLGvsKUAxUAAAAAHQAAAAAQ-AE\">https:\/\/www.ego-gw.it\/blog\/2023\/05\/24\/i-rivelatori-di-onde-gravitazionali-stanno-iniziando-un-nuovo-periodo-osservativo-in-cui-esploreranno-i-segreti-delluniverso\/<\/a><\/figcaption><\/figure>\n<p><span style=\"font-weight: 400\">Future projects for gravitational-wave detection include the Einstein Telescope and the Cosmic Explorer, terrestrial interferometers \u2014 the former European and the latter American \u2014 tasked with observing sources at very high redshift and testing general relativity and cosmology. These will be complemented by LISA (Laser Interferometer Space Antenna), a space-based interferometer engineered by ESA and NASA, which will enable even more detailed investigation of the primordial gravitational universe. Our researcher <span style=\"color: #99ccff\"><strong>Matteo Calabrese<\/strong><\/span> is working on preparatory studies for the LISA mission.<\/span><\/p>\n<p><span style=\"font-weight: 400\">Although we cannot be certain of its global effects, a gravitational wave originating one hundred light-years from Earth would probably not bring about disastrous consequences for the planet\u2019s climate or geology: its interaction with matter would in fact be minimal, and the caused spacetime distortion measurable only by the most sensitive interferometers. By contrast, a gamma-ray burst at the same distance could inflict irreparable damage, releasing an energy of approximately 10<sup>50<\/sup> erg \u2014 that is, about 10<sup>8 <\/sup>times the Sun\u2019s annual output \u2014 focused into a narrow cone over just a few seconds. If, as hypothesised by Egan in <\/span><i><span style=\"font-weight: 400\">Diaspora<\/span><\/i><span style=\"font-weight: 400\">, the Earth lay along the jet axis, it would be fully exposed to the gamma rays, which would ionise the stratosphere and destroy almost all of the ozone present. This would allow the immediate penetration of solar ultraviolet radiation, particularly harmful to DNA and biological organisms, against which ozone normally acts as a shield; without this natural filter, the Earth would hence be rendered uninhabitable for living beings. Only the artificial intelligences of the <\/span><i><span style=\"font-weight: 400\">polises<\/span><\/i><span style=\"font-weight: 400\"> could survive, given that they are devoid of physical bodies and isolated from the external world, with which they interact solely on a digital level.<\/span><\/p>\n<p><span style=\"font-weight: 400\">Gravitational waves are silent messengers of remote cataclysms; nevertheless, if one were to occur \u201cjust\u201d one hundred light-years from us, that silence could become deafening: only a handful of well-collimated gamma rays could annihilate life as we know it. Thankfully, this threat is mitigated by the absence of any binary system of compact objects in the Earth\u2019s immediate vicinity. By comparing observational data from events like GW170817 with the conjectures formulated by Egan in <\/span><i><span style=\"font-weight: 400\">Diaspora<\/span><\/i><span style=\"font-weight: 400\">, one can appreciate the power of science fiction literature to anticipate scenarios that have not yet occurred, but remain physically plausible. It is in this space of possibility, between calculation and imagination, that hope is nurtured for discoveries that could revolutionise our vision of the cosmos<\/span><span style=\"font-weight: 400\">.<\/span><\/p>\n<p><em>Nus, 2 August 2025 &#8211; English version published on 18 May 2026<\/em><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"text-decoration: underline;color: #ffcc00\"><b>Astroglossary<\/b><\/span><\/p>\n<p><span style=\"font-weight: 400\"><strong>m<\/strong>: metre<\/span><span style=\"font-weight: 400\"><br \/>\n<\/span><span style=\"font-weight: 400\"><strong>s<\/strong>: second<\/span><span style=\"font-weight: 400\"><br \/>\n<\/span><span style=\"font-weight: 400\"><strong>hz<\/strong>: hertz, unit of measurement for frequency<\/span><span style=\"font-weight: 400\"><br \/>\n<\/span><span style=\"font-weight: 400\"><strong>G<\/strong>: gauss, unit of measurement of the magnetic field in the CGS system, corresponding to 10<sup>-4<\/sup> T, the symbol for the tesla<\/span><span style=\"font-weight: 400\"><br \/>\n<\/span><span style=\"font-weight: 400\"><strong>erg<\/strong>: unit of measurement of energy in the CGS system, equivalent to 10\u207b\u2077 J, symbol for the joule<\/span><span style=\"font-weight: 400\"><br \/>\n<\/span><span style=\"font-weight: 400\"><strong>light-year<\/strong>: distance traveled by light in a year in a vacuum, corresponding to <\/span><span style=\"font-weight: 400\">9,46 <em>\u00d7<\/em> <\/span><span style=\"font-weight: 400\">10<\/span><span style=\"font-weight: 400\"><sup>12<\/sup><\/span><span style=\"font-weight: 400\"> km<\/span><span style=\"font-weight: 400\"><br \/>\n<\/span><span style=\"font-weight: 400\"><strong>solar mass<\/strong>: massa of the star Sun, corresponding to <\/span><span style=\"font-weight: 400\">1,9885 <em>\u00d7<\/em> <\/span><span style=\"font-weight: 400\">10<\/span><span style=\"font-weight: 400\"><sup>30<\/sup><\/span><span style=\"font-weight: 400\"> kg<\/span><\/p>\n<p><span style=\"text-decoration: underline;color: #ffcc00\"><b>References<\/b><\/span><\/p>\n<p><a href=\"https:\/\/www.mondourania.com\/urania\/u1441-1460\/urania1460.htm\">Greg Egan, <em>Diaspora<\/em><span style=\"font-weight: 400\">, translated by Riccardo Valla, Urania n. 1460, Edizioni Mondadori, 2003<\/span><\/a>, in Italian<\/p>\n<p><a href=\"https:\/\/www.isfdb.org\/cgi-bin\/title.cgi?1399\">Internet Speculative Fiction Database: Greg Egan, <em>Diaspora<\/em>, every edition<\/a><\/p>\n<p><a href=\"https:\/\/www.gregegan.net\/DIASPORA\/04\/04.html\">Greg Egan, &#8220;Gravitational Waves from Binary Neutron Stars&#8221;, with explanations, calculations, and animations by the author, 1997-1998<\/a><\/p>\n<p><a href=\"https:\/\/arxiv.org\/abs\/0903.4877\"><span style=\"font-weight: 400\">Scott A. Hughes, &#8220;Gravitational waves from merging compact binaries&#8221;, <em>Ann.Rev.Astron.Astrophys.<\/em> <strong>47<\/strong>, pp. 107-157, 2009<\/span><\/a> (arxiv)<\/p>\n<p><a href=\"https:\/\/www.media.inaf.it\/2017\/10\/16\/nuova-era-universo\/\">Comunicato congiunto ASI INAF INFN, &#8220;Una nuova era per l&#8217;osservazione dell&#8217;universo&#8221;, 2017<\/a>, in Italian<\/p>\n<p id=\"title\"><a href=\"https:\/\/svs.gsfc.nasa.gov\/12740\/\">NASA Scientific Visualization Studio, &#8220;Doomed Neutron Stars Create Blast of Light and Gravitational Waves&#8221;, 2017<\/a>; video also on <a href=\"https:\/\/www.youtube.com\/watch?v=x_Akn8fUBeQ\">YouTube<\/a><\/p>\n<p><a href=\"https:\/\/arxiv.org\/abs\/1607.03540\"><span style=\"font-weight: 400\">Luca Baiotti and Luciano Rezzolla, &#8220;Binary neutron-star mergers: a review of Einstein&#8217;s richest laboratory&#8221;, <em>Rep. Prog. Phys.<\/em>\u00a0<b>80<\/b> 096901, 2017<\/span><\/a> (arxiv)<\/p>\n<p><a href=\"https:\/\/accademiadellacrusca.it\/it\/contenuti\/la-nuova-astronomia--multimessaggera\/6203\">INFN e Accademia della Crusca, &#8220;La nuova astronomia \u00e8 \u201cmultimessaggera\u201d &#8211; L\u2019Istituto Nazionale di Fisica Nucleare e L\u2019Accademia della Crusca hanno concordato la terminologia corretta&#8221;, 2018<\/a>, in Italian<\/p>\n<p><a href=\"https:\/\/astrobiology.nasa.gov\/news\/how-deadly-would-a-nearby-gamma-ray-burst-be\/\"><span style=\"font-weight: 400\">Aaron Gronstal, &#8220;<\/span><\/a><a href=\"https:\/\/astrobiology.nasa.gov\/news\/how-deadly-would-a-nearby-gamma-ray-burst-be\/\"><span style=\"font-weight: 400\">How deadly would a nearby gamma-ray burst be?&#8221;, Astrobiology at NASA<\/span><\/a><\/p>\n<p><a href=\"https:\/\/web.oapd.inaf.it\/mapelli\/lecture1_mapelli.pdf\">Michela Mapelli, &#8220;Gravitational waves for dummies &amp; observational facts&#8221;, slides for a lesson at the University of Padua, 2020<\/a><\/p>\n<p><a href=\"https:\/\/arxiv.org\/abs\/2410.19145\"><span style=\"font-weight: 400\">T. A. Callister, &#8220;Observed gravitational-wave populations&#8221;, preprint di un capitolo del volume <em>Encyclopedia of Astrophysics, 1st ed. <\/em>(Editor-in-Chief Ilya Mandel, Section Editor Jeff Andrews) con pubblicazione annunciata da Elsevier a settembre 2025<\/span><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>\ud83d\udc49 <em><a href=\"https:\/\/www.oavda.it\/editoriale\/centenario-della-fantascienza\">Click here<\/a> for other articles of the series Sci-fi Astronomy, edited by Camilla Pianta<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>*Sci-fi Astronomy, edited by Camilla Pianta* Diaspora, the twilight of Earth in the echo of gravitational waves \ud83d\udcab What if a neutron star collision happened in our galactic backyard? COUNTDOWN TO APRIL 2026, THE CENTENARY OF SCIENCE FICTION: -8 \u00a0 Clicca qui per la versione italiana di questo articolo &nbsp; By one o\u2019clock in the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":17409,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[327,322,330],"tags":[],"class_list":["post-19063","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-iniziative-archivio","category-news-en","category-sci-fi-astronomy"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v26.8 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Astronomia da fantascienza \ud83d\udc49 -8 - Osservatorio Astronomico della Regione Autonoma Valle d&#039;Aosta<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.oavda.it\/en\/news-en\/astronomia-da-fantascienza-8\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Astronomia da fantascienza \ud83d\udc49 -8 - Osservatorio Astronomico della Regione Autonoma Valle d&#039;Aosta\" \/>\n<meta property=\"og:description\" content=\"*Sci-fi Astronomy, edited by Camilla Pianta* Diaspora, the twilight of Earth in the echo of gravitational waves \ud83d\udcab What if a neutron star collision happened in our galactic backyard? 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