Every Type Of Alien That Could Actually Exist

Somewhere out there, there could be living balloons the size of cities, creatures that breathe out sand, and a whole civilization on a dead star that lives a million times faster than you. This video goes through every type of alien life science can imagine: from life built just like us, through mirror life, silicon life and microbes drifting in the acid clouds of Venus, to self-copying plasma dust, machine minds and the tiny flat cheela of a neutron star. Every alien gets an honest status: real, possible, hypothesis, disputed, thought experiment, computer simulation, educated guess or science fiction. And in every chapter Karakulya turns into that alien: a tardigrade, a crystal that coughs up sand, a living balloon, a robot, a pancake. Every number in this video is checked against the sources below. A few comparisons are our own rounded calculations from published values: Earth's crust has hundreds of times more silicon than carbon; a planet with no star should cool to about minus 240 °C; while you watch this video, a cheela would live through about twenty years. Which one do you think we'll find first? Tell me in the comments. #space #aliens #astrobiology 0:00 Intro: balloons, sand and a dead star 0:18 Life like us 1:07 The survivors 1:58 Our Martian cousins 2:47 Mirror life 3:38 Silicon life 4:31 Ammonia life 5:22 Cloud life 6:21 The floaters 7:22 Life in the dark 8:13 Plasma life 9:00 Machine life 9:54 Life on a dead star 10:48 Which one will we find first? Sources Water and carbon in the human body: https://en.wikipedia.org/wiki/Body_water At least 300 million potentially habitable planets (Bryson et al.): https://arxiv.org/abs/2010.14812 Tardigrades survive open space, FOTON-M3 2007 (Jönsson et al.): https://www.sciencedaily.com/releases... Strain 121 grows at 121 °C: https://en.wikipedia.org/wiki/Strain_121 Extremophiles: https://en.wikipedia.org/wiki/Extremo... Perseverance's potential biosignature, Cheyava Falls (NASA, 2025): https://www.nasa.gov/news-release/nas... Hurowitz et al. 2025, Nature: https://www.nature.com/articles/s4158... Bacteria survive 3 years outside the space station (Kawaguchi et al. 2020): https://www.frontiersin.org/journals/... Homochirality: life's left and right hands: https://en.wikipedia.org/wiki/Homochi... Pasteur sorts mirror crystals, 1848: https://en.wikipedia.org/wiki/Louis_P... Mirror life and the 2024 warning in Science: https://en.wikipedia.org/wiki/Mirror_... Silicon, ammonia and neutron-star life (Haldane 1954, Drake 1973): https://en.wikipedia.org/wiki/Hypothe... Bacteria make carbon-silicon bonds (Kan et al. 2016, Caltech): https://www.caltech.edu/about/news/br... Diatoms build glass shells: https://ucmp.berkeley.edu/chromista/d... Venus's Earth-like cloud layer: https://www.universetoday.com/article... Life in the Clouds of Venus? (Morowitz & Sagan 1967): https://www.nature.com/articles/21512... Phosphine on Venus, ALMA reanalysis (Greaves et al.): https://arxiv.org/abs/2010.14305 Amino acids in concentrated sulfuric acid (Seager et al. 2024): https://arxiv.org/abs/2401.01441 Sinkers, floaters and hunters (Sagan & Salpeter 1976): https://www.planetary.org/blogs/guest... The 1952 Miller-Urey experiment: https://en.wikipedia.org/wiki/Miller%... Life-sustaining planets in interstellar space (Stevenson 1999): https://lindecenter.caltech.edu/news/... Free-floating planets per star (Sumi et al. 2023): https://arxiv.org/abs/2303.08280 Hydrothermal vent ecosystems: https://en.wikipedia.org/wiki/Hydroth... Plasma dust forms DNA-like helices (Tsytovich et al. 2007): https://www.sciencedaily.com/releases... Intelligent aliens are likely machines (Seth Shostak): https://www.space.com/34713-intellige... Neutron stars: https://en.wikipedia.org/wiki/Neutron... Dragon's Egg (Robert L. Forward, 1980): https://en.wikipedia.org/wiki/Dragon%...