Interstellar material has been discovered in our solar system, but researchers continue to hunt for where it came from and how it got here. A new study led by Western astrophysicists Cole Gregg and Paul Wiegert recommends Alpha Centauri—the next closest solar system to ours—is a great place to start, highlighting how and why it’s a prime target.
The findings were published March 6 in The Planetary Science Journal.
Interstellar objects are astronomical material, like asteroids or comets, not gravitationally bound to a star. They can come from other solar systems and be thrown into interstellar space by collisions or be slingshotted by a planet or star’s gravity.
Asteroids that orbit close to the Earth inevitably cause us some anxiety due to the even remote possibility of a collision. But their proximity also offers ample opportunities to learn more about the universe. Ryugu, a 900-meter diameter asteroid in the Apollo belt, has recently proven useful in our search for signs of life’s precursors elsewhere in our solar system.
A team of researchers at Kyoto University have found evidence of salt minerals in samples recovered from Ryugu during the initial phase of Japan’s Hayabusa2 mission. The discovery of these deposits, containing sodium carbonate, halite, and sodium sulfates, suggest that liquid saline water once existed within a parent body of Ryugu.
Before examining the samples, the team expected that sample grains returned from the asteroid might contain substances not generally found in meteorites. They anticipated that these could be highly water-soluble materials, which readily react with moisture in Earth’s atmosphere and are difficult to detect unless examined in their pristine state as preserved in the vacuum of space.
Technology may one day grant us a Utopia in which virtually all tasks are performed by robots and artificial intelligence. In such a post-scarcity civilization, people may have difficulty finding a purpose to existence. Today we will explore how this may come about, what the consequences of this existential threat might be, and what purposes people may find for themselves in such a future.
Join this channel to get access to perks: / @isaacarthursfia. Visit our Website: http://www.isaacarthur.net. Join Nebula: https://go.nebula.tv/isaacarthur. Support us on Patreon: / isaacarthur. Support us on Subscribestar: https://www.subscribestar.com/isaac-a… Group: / 1,583,992,725,237,264 Reddit: / isaacarthur Twitter: / isaac_a_arthur on Twitter and RT our future content. SFIA Discord Server: / discord Listen or Download the audio of this episode from Soundcloud: Episode’s Audio-only version: / purpose Episode’s Narration-only version: / purpose-narration-only Credits: Post-Scarcity Civilizations: Purpose ep 140 Season 4, Episode 26 Writers: Isaac Arthur Editors: A.T. Long Darius Said Dillon Olander Jerry Guern Justin Dixon Mark Warburton Matthew Acker Matthew Campbell Producer: Isaac Arthur Cover Artist: Jakub Grygier https://www.artstation.com/jakub_grygier Graphics Team Jeremy Jozwik Justin Dixon Ken York Kristijan Tavcar Narrator Isaac Arthur Music Manager: Luca De Rosa — lucaderosa2@live.com Music: Dracovallis, “Cynthia” https://dracovallis.bandcamp.com/ Stellardrone, “Breathe In The Light” https://stellardrone.bandcamp.com Kai Engel, “Endless Story About Sun and Moon” https://www.kai-engel.com/ Chris Zabriskie, “A New Day in a New Sector” http://chriszabriskie.com Kai Engel, “Morbid_Imagination” https://www.kai-engel.com/ Aerium, “The Islands moved while I was asleep” / @officialaerium Lombus, “Cosmic Soup” https://lombus.bandcamp.com Brandon Liew, “Into the Storm” • Video. Facebook Group: / 1583992725237264 Reddit: / isaacarthur. Twitter: / isaac_a_arthur on Twitter and RT our future content. SFIA Discord Server: / discord.
Listen or Download the audio of this episode from Soundcloud: Episode’s Audio-only version: / purpose. Episode’s Narration-only version: / purpose-narration-only.
Credits: post-scarcity civilizations: purpose. ep 140 season 4, episode 26
Humanity came close to extinction 800,000 years ago. Only 1,280 of our ancestors survived.
A recent study published in Science suggests that a catastrophic “ancestral bottleneck” reduced the global population to just 1,280 breeding individuals, wiping out 98.7% of the early human lineage.
This population crash, lasting about 117,000 years, likely resulted from extreme climate shifts, prolonged droughts, and dwindling food sources.
Using a groundbreaking genetic analysis method called FitCoal, researchers analyzed modern human genomes to trace this dramatic decline, potentially explaining a gap in the African and Eurasian fossil record.
Despite the near-extinction, this bottleneck may have played a crucial role in shaping modern humans. Scientists believe it contributed to a key evolutionary event—chromosome fusion—which may have set Homo sapiens apart from earlier hominin species, including Neanderthals and Denisovans. The study raises intriguing questions about how this small population survived, possibly through early fire use and adaptive intelligence. Understanding this ancient crisis helps scientists piece together the story of human evolution and the resilience that allowed our species to thrive against all odds.
2024 YR4 is no longer a danger for Earth, and a (small) chance of a lunar impact could provide great science data.
“We are all rooting for the Moon!” Richard Binzel (MIT) is referring to the asteroid 2024 YR4, which for a few weeks had remained at the second-highest-rated probability of potential Earth impact of any asteroid discovered. Now, although its impact probability has fallen to virtually zero for Earth, it still has a slight chance of impacting the Moon on December 22, 2032.
The year one hundred two thousand twenty-three. A giant meteorite the size of Pluto is approaching the Solar System. It flies straight to Earth. But as the meteorite crosses Saturn’s orbit, a swarm of miner probes approaches it. The scan revealed no minerals on the object, so the searches returned with nothing. Meanwhile, the Space Security Center in Alaska military personnel are setting up a laser. The Solar System witnesses a sudden flare and nothing remains of the dwarf-sized meteorite. Now, unless hydrogen miners on Jupiter post videos of another annihilation on social media… This is what the world will look like when humanity finally becomes a Type Two civilization on the Kardashev scale. We’ll have almost infinite energy reserves, the ability to prepare for interstellar flights, or to instantly destroy any threat. But will humanity really be safe? And what can ruin a Type Two civilization?
“Retrocausality” by Antonella Vannini and Ulisse Di Corpo Book Link: https://amzn.to/3X6UGhx. “Time Loops: Precognition, Retrocausation, and the Unconscious” by Eric Wargo Book Link: https://amzn.to/4bdmWVV “Psychology and Retrocausality: How the Future Determines Love, Memory, Evolution, Learning, Depression, Death, and What It Means to Be Human” by Mark Hatala Book Link: https://amzn.to/4k7kdBj.
The exploration of retrocausality challenges classical views of time and causality, suggesting that effects can precede their causes, influencing our understanding of quantum mechanics, consciousness, and free will. Retro causality offers potential resolutions to issues like non-locality in quantum physics by allowing communication between particles to travel backward in time, which could eliminate the need for higher dimensional configuration spaces and reconcile quantum theory with special relativity. Experimental investigations into retro-causality involve analyzing subtle effects, such as heart rate variations, and require careful methodologies to distinguish genuine retrocausal phenomena from experimental artifacts, while theoretical frameworks explore how retrocausality might address paradoxes and be compatible with concepts like time symmetry. Thinkers in physics and philosophy are increasingly considering retrocausality as a potential framework to address foundational issues, including the measurement problem and the reconciliation of quantum mechanics with general relativity, potentially impacting our comprehension of time, causality, and the nature of reality itself. Discussions around retrocausality extend into areas like decision theory, existential risk, and the nature of consciousness, with some researchers exploring goal-oriented approaches and the potential for retrocausality to enhance artificial intelligence and our understanding of human cognition. Some notable scientists involved: • Roger Penrose is noted for his views aligning with retrocausal concepts and his work on the science of consciousness with Stuart Hameroff. • Yakir Aharonov is cited regarding time in quantum mechanics and weak value amplification. • Ruth Kastner is mentioned in the context of retrocausality and the transactional interpretation of quantum mechanics. • Hu Price’s work is at the center of the study of existential risk. • Ken Wharton is a professor of physics and astronomy working on time-symmetric and causally neutral models of physics. • Matthew Leifer is mentioned regarding block universe ontological models and frameworks for theories with retrocausality. • Daniel Rohrlich is mentioned for his work on fundamental aspects of quantum mechanics and his views on retrocausality. • Richard Feynman is mentioned in the context of interaction with the absorber as the mechanism of radiation. • Simon Shnoll is mentioned for his work showing that the assumption of normal distribution is only mathematical, and that in life sciences and also in physics it is false. • David Lucas is mentioned in the context of trapped-ion processing modules.
What if the “magic” of tomorrow is just science we don’t yet understand? In this episode, we explore the wildest speculative technologies—faster-than-light travel, Dyson Spheres, teleportation, wormholes, and more. Could these breakthroughs redefine our future or explain the Fermi Paradox? Find out as we dive into the impossible! Watch my exclusive video Big Alien Theory https://nebula.tv/videos/isaacarthur–… Nebula using my link for 40% off an annual subscription: https://go.nebula.tv/isaacarthur Get a Lifetime Membership to Nebula for only $300: https://go.nebula.tv/lifetime?ref=isa… Use the link gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $30. Visit our Website: http://www.isaacarthur.net Join Nebula: https://go.nebula.tv/isaacarthur Support us on Patreon: / isaacarthur Support us on Subscribestar: https://www.subscribestar.com/isaac-a… Facebook Group: / 1,583,992,725,237,264 Reddit: / isaacarthur Twitter: / isaac_a_arthur on Twitter and RT our future content. SFIA Discord Server: / discord Credits: Impossible Technologies: The Clarketech Compendium Episode 486a; February 16, 2025 Written, Produced & Narrated by: Isaac Arthur Editors: Ludwig Luska, Thomas Owen, Lukas Konecny Graphics: Jeremy Jozwik, Ken York YD Visual, Mihail Yordanov, Sergio Botero Select imagery/video supplied by Getty Images Music Courtesy of Epidemic Sound http://epidemicsound.com/creator Phase Shift, “Forest Night” Chris Zabriskie, “Unfoldment, Revealment”, “A New Day in a New Sector”, “Oxygen Garden” Stellardrone, “Red Giant”, “Billions and Billions” Lombus, “Hydrogen Sonata” “Cosmic Soup” Segments/Breaks 0:00 Intro 2:00 Defining Clarketech 5:00 Fermi Paradox & Implications 7:59 Ascension Machines & Apotheosis 10:53 Anti-Gravity 13:00 Attotech 14:57 Dark Matter Manipulation 17:02 Disintegration Devices 21:07 Dyson Sphere 25:52 Big Alien Theory 27:17 Entropy Manipulation 32:37 Faster-than-Light Travel (FTL) 35:06 Femtotech 38:36 Field Nullifiers & Amplifiers 41:17 Hammerspace 43:59 Kugelblitz Black Holes 47:36 Magmatter 50:02 Mass Manipulation 52:05 Matter-to-Energy Conversion 56:31 Negative Matter & Mass 58:07 Neutronium 59:47 Parallel Universes & Alternate Realities 1:01:47 Perpetual Motion Machine 1:05:06 Photogravitics & Photoneutrino Devices 1:07:32 Probability Manipulation 1:08:33 Reactionless Drive 1:10:08 SFIA Intermission 1:10:46 Slow Time Fields 1:12:52 Subverse Creation 1:14:11 Technological Suppression Zones 1:16:40 Teleportation & Gateways 1:18:14 Tachyon Tech 1:20:32 Time Manipulation 1:23:27 Utility Fog & Smart Matter 1:27:06 Wormholes 1:28:39 Zero Point Energy 1:30:20 Outro.
