<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto">Very, very interesting. I’m not well versed enough with the science to make any conjecture, however the Science Fantasy part of my brain is going wild. <br><br><div dir="ltr">SR Ballard</div><div dir="ltr"><br><blockquote type="cite">On Aug 26, 2021, at 9:53 AM, John Grigg via extropy-chat <extropy-chat@lists.extropy.org> wrote:<br><br></blockquote></div><blockquote type="cite"><div dir="ltr"><div dir="ltr"><p style="font-family:"Open Sans",Arial,sans-serif;margin:0px 0px 1em;padding:0px;border:0px;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-stretch:inherit;line-height:1.5;vertical-align:baseline;color:rgb(51,51,51)"><font size="4">"Aliens could place a large satellite in a stable orbit around a black hole and then collect X-ray energy using something akin to solar panels, study coauthor Tomotsugu Goto, also of National Tsing Hua University, told Live Science. </font></p><div id="gmail-bordeaux-static-slot-8" style="font-family:"Open Sans",Arial,sans-serif;margin:auto;padding:0px;border:0px;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-stretch:inherit;line-height:inherit;vertical-align:baseline;color:rgb(51,51,51);display:flex"></div><p style="font-family:"Open Sans",Arial,sans-serif;margin:0px 0px 1em;padding:0px;border:0px;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-stretch:inherit;line-height:1.5;vertical-align:baseline;color:rgb(51,51,51)"><font size="4">They might also build a ring-like structure around the black hole or totally surround it with platforms, much like in Freeman Dyson's original proposal, Goto added, though each of these would be increasingly complex and challenging to construct.</font></p><div id="gmail-bordeaux-static-slot-7" style="font-family:"Open Sans",Arial,sans-serif;margin:auto;padding:0px;border:0px;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-stretch:inherit;line-height:inherit;vertical-align:baseline;color:rgb(51,51,51);display:flex"></div><p style="font-family:"Open Sans",Arial,sans-serif;margin:0px 0px 1em;padding:0px;border:0px;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-stretch:inherit;line-height:1.5;vertical-align:baseline;color:rgb(51,51,51)"><font size="4">In either case, a black hole could radiate up to 100,000 times more energy than a star like the sun, meaning that a celestial species would have a lot of power to work with, the researchers wrote in a paper published July 1 in the journal <a href="https://academic.oup.com/mnras/article-abstract/506/2/1723/6312510" class="gmail-hawk-link-parsed" style="font-family:inherit;margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;line-height:inherit;vertical-align:baseline;color:rgb(2,108,162);text-decoration-line:none"><u style="font-family:inherit;margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;line-height:inherit;vertical-align:baseline">Monthly Notices of the Royal Astronomical Society</u></a>. </font></p><div id="gmail-bordeaux-static-slot-6" style="font-family:"Open Sans",Arial,sans-serif;margin:auto;padding:0px;border:0px;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-stretch:inherit;line-height:inherit;vertical-align:baseline;color:rgb(51,51,51);display:flex"></div><p style="font-family:"Open Sans",Arial,sans-serif;margin:0px 0px 1em;padding:0px;border:0px;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-stretch:inherit;line-height:1.5;vertical-align:baseline;color:rgb(51,51,51)"><font size="4">After being absorbed and used, the energy from a cosmic object would have to be reradiated or else it would build up and eventually melt the Dyson sphere, as Dyson noted <a href="https://science.sciencemag.org/content/131/3414/1667" class="gmail-hawk-link-parsed" style="font-family:inherit;margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;line-height:inherit;vertical-align:baseline;color:rgb(2,108,162);text-decoration-line:none"><u style="font-family:inherit;margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;line-height:inherit;vertical-align:baseline">in his 1960 paper</u></a>. This energy would be shifted to longer wavelengths, so a Dyson sphere around a black hole might give off an unexplainable energy signature in the ultraviolet or infrared, the researchers said. </font></p><div id="gmail-bordeaux-static-slot-5" style="font-family:"Open Sans",Arial,sans-serif;margin:auto;padding:0px;border:0px;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-stretch:inherit;line-height:inherit;vertical-align:baseline;color:rgb(51,51,51);display:flex"></div><p style="font-family:"Open Sans",Arial,sans-serif;margin:0px 0px 1em;padding:0px;border:0px;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-stretch:inherit;line-height:1.5;vertical-align:baseline;color:rgb(51,51,51)"><font size="4">Several instruments, including NASA's space-based Wide-field Infrared Survey Explorer (WISE) and the Pan-STARRS telescope in Hawaii, have cataloged billions of objects during their detailed surveys of the night sky, Goto said. Should Dyson spheres around black holes actually exist, it's possible that their telltale signs have already been recorded by such detectors, he added."</font></p><div><font size="4"><a href="https://www.livescience.com/alien-dyson-spheres-suck-black-hole-energy.html">https://www.livescience.com/alien-dyson-spheres-suck-black-hole-energy.html</a></font><br></div></div>
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