Kurzgesagt – In a Nutshell
Kurzgesagt – In a Nutshell
Embedded Files
Sources – Meet the Aliens
Sources – Meet the Aliens
Thanks to our experts:
Dr. Sanjoy Som
NASA/Blue Marble Space
Dr. Graham Lau
Blue Marble Space
Dr. Matt Caplan
Illinois State University
The planets and species in this video, with the exception of those on Earth, are fictional.
—What do real aliens look like? We know that life on earth is incredibly diverse and exists in the most strange and extreme places, from Blue Dragon sea slugs, to Aye-Ayes, or Chrysomallon snails with shells of iron. Or whatever this is supposed to be.
Life of Earth can exist in an extreme range of environments and conditions.
#McKay, Christopher (2014): “Requirements and limits for life in the context of exoplanets”, Proceedings of the National Academy of Sciences, vol.111, 35, 12628-12633
https://www.pnas.org/doi/full/10.1073/pnas.1304212111
#EOL: “Blue Dragon (Glaucus atlanticus)” (retrieved 2024)
#EOL: “Aye Ayes (Daubentoniidae)” (retrieved 2024)
#Red List: “Scaly-foot Snail (Chrysomallon squamiferum)” (retrieved 2024)
https://www.iucnredlist.org/species/103636217/103636261
#WoRMS image (2019): “Scaly-foot snail”
https://www.marinespecies.org/aphia.php?p=image&pic=130293&tid=736932
The last featured creature is Mochi, a pug dog and Kurzgesagt’s Chief Cuddles Executive
#Encyclopedia Britannica: “Pug” (retrieved 2024)
https://www.britannica.com/animal/pug
#Kurzgesagt: “Who we are” (retrieved 2024)
—This is the red dwarf star Oculus, five times smaller than our sun and a lot less bright. A bit larger than earth but orbiting its star twenty times closer, you see the ice hell of the planet Ipa. It is tidally locked, so one side is experiencing a never ending night and the other an eternal day, lit by the star’s dim glow.
Oculus and Ipa are inspired by Ross 508 and its planet Ross 508 b.
#Harakawa, Hiroki et al. (2022): “A super-Earth orbiting near the inner edge of the habitable zone around the M4.5 dwarf Ross 508”, Publications of the Astronomical Society of Japan, vol. 74, 4, 904–922
https://academic.oup.com/pasj/article/74/4/904/6623879
Red Dwarf stars are likely places for life to arise, because they are the most abundant type of star
#Encyclopedia Britannica: “Red Dwarf Star” (retrieved 2024)
https://www.britannica.com/science/red-dwarf-star
Quote: “In the Milky Way Galaxy, about three-fourths of the stars are red dwarfs. The proportion is even higher in elliptical galaxies.”
#Haqq-Misra, Jacob; Kopparapu, Ravi K.; Wolf, Eric T. (2017): ”Why do we find ourselves around a yellow star instead of a red star?”, International Journal of Astrobiology, vol. 17, 1, 77–86
https://ntrs.nasa.gov/api/citations/20190002439/downloads/20190002439.pdf
Quote:“M-dwarf stars are more numerous than other stellar types and comprise about 75% of the galactic main sequence stellar population”
They also have a relatively high chance of having rocky planets around them
#Haqq-Misra, Jacob; Kopparapu, Ravi K.; Wolf, Eric T. (2017): ”Why do we find ourselves around a yellow star instead of a red star?”, International Journal of Astrobiology, vol. 17, 1, 77–86
https://ntrs.nasa.gov/api/citations/20190002439/downloads/20190002439.pdf
Quote: “The occurrence of rocky planets in the habitable zone around M-dwarf stars is *20% (Dressing & Charbonneau 2015), similar to the occurrence rate of 22% for G- and K-dwarf stars (Petigura et al. 2013). “
They may keep their atmospheres even despite intense UV radiation that Red Dwarf stars impose on the planets that have to orbit very close to them to stay in the liquid water habitable zone.
#Badhan, Mahmuda Afrin et al. (2019): “Stellar Activity Effects on Moist Habitable Terrestrial Atmospheres Around M dwarfs”, The Astrophysical Journal, vol. 887,1
https://ntrs.nasa.gov/api/citations/20205001153/downloads/20-19.pdf
Tidal locking is common among exoplanets, and even more so among exoplanets orbiting close to their stars:
#Barnes, Rory (2017): “Tidal locking of habitable exoplanets”, Celestial Mechanics and Dynamical Astronomy, vol. 129, 509–536.
https://link.springer.com/article/10.1007/s10569-017-9783-7
For an accessible explanation of tidal locking, check:
#NASA: “Tidal Locking” (retrieved 2024)
—In the region facing the dim star directly, temperatures are warm and pleasant. The hell of ice has melted into a shallow, black ocean: the Eye of Ipa. About the size of Europe, barely 200 meters at its deepest points, churned by a never ending storm where hot air is meeting the frigid winds from the icy outskirts. But below this inhospitable chaos we find calm stability, an ecosystem in almost perfect balance.
This aspect of Ipa as an ‘eyeball planet’ is inspired by LHS 1140b:
#University of Montereal News (2024): “Found with Webb: a potentially habitable world”
https://nouvelles.umontreal.ca/en/article/2024/07/08/found-with-webb-a-potentially-habitable-world/
#University of Michigan News (2024): “Astronomers find surprising ice world in the habitable zone with JWST data” https://news.umich.edu/astronomers-find-surprising-ice-world-in-the-habitable-zone-with-jwst-data/
Quote: “Current models indicate that if LHS 1140 b has an Earth-like atmosphere, it would be a snowball planet with a bull’s-eye ocean about 4,000 kilometers in diameter, equivalent to half the surface area of the Atlantic Ocean. The surface temperature at the center of this alien ocean could even be a comfortable 20 degrees Celsius.”
#Cadieux, Charles et al. (2024): ”Transmission Spectroscopy of the Habitable Zone Exoplanet LHS 1140 b with JWST/NIRISS”, The Astrophysical Journal Letters, vol. 970, 1
https://iopscience.iop.org/article/10.3847/2041-8213/ad5afa
The depth of the ocean is only estimated to fit the narrative.
—Let’s dive in. Instead of meeting open water we splash into a floating underwater jungle. We know places like this at home: kelp forests made from seaweeds up to 65 meters long, sheltering countless smaller creatures.
Kelp forests are found frequently in shallow waters. They are a type of macroalgae:
#NOAA: “What is a kelp forest?” (retrieved 2024)
https://oceanservice.noaa.gov/facts/kelp.html
#NASA Earth Observatory (2015): “Floating Forests Revealed”
https://earthobservatory.nasa.gov/images/85023/floating-forests-revealed
The kelp in Ipa is only slightly larger than the one on Earth:
#Monterey Bay Aquarium: “Giant kelp (Macrocystis pyrifera)” (retrieved 2024)
https://www.montereybayaquarium.org/animals/animals-a-to-z/giant-kelp
Quote: “Size: Up to 100 feet (30 m); 175 feet (53 m) in ideal conditions”
—On earth we get abundant white sunlight so our plants evolved to be green, absorbing the most useful red wavelengths for photosynthesis and reflecting away the rest. But oculus shines not nearly as bright and its dim rays are even further dulled by the storm. So here plants are a deep black to make use of the weak infrared leftovers. Which also gives the Eye of Ipa its striking black colour.
Different stars emit different sorts of light, which gets absorbed by atmospheres of different compositions. Plants on the ground have to then make use of the light that filters through.
The result is a huge range of interesting ‘optimal’ plant colours, from familiar green to deep purple. For organisms sheltering underwater, there is additional filtering. Shallow sea plants may need to be black to get enough energy from a dim red dwarf star.
#Kiang, Nancy K. (2008): “The Color of Plants on Other Worlds” Scientific American
Quote: “The range of M-star temperatures makes possible a very wide variation in alien plant colors.A planet around a quiescent M star would receive about half the energy that Earth receives from our sun. Although that is plenty for living things to harvest—about 60 times more than the minimum needed for shade-adapted Earth plants— most of the photons are near-infrared. Evolution might favor a greater variety of photosynthetic pigments to pick out the full range of visible and infrared light. With little light reflected, plants might even look black to our eyes”
—Over billions of years, the jungle has occupied all possible space in the Eye. Its roots extend deep into the seabed mud, anchoring them and providing access to nutrients. They drop their seeds in the few free spaces in the mud, only death makes room for new life.
The forest in the Eye is saturated with plants, much like some tropical forests on Earth, so only the death and fall of one of them can create a disturbance from which new plants can grow.
#Martínez-Ramos, Miguel; Alvarez-Buylla, Elena; Sarukhán, José (1989): ”Tree Demography and gap dynamics in a tropical rainforest”, Ecology, vol.7, 3, 555-558
http://www.oikos.unam.mx/LECT/images/publicaciones-1990/mmreajs_1989.pdf
—Big and streamlined teardrop-shaped creatures push through the dark water. They kind of look like… fish? Just like many sea creatures on earth, their shape is optimised for the lowest drag when travelling through water. Like underwater cattle they lazily swim through the forest, grazing on leaves in peace.
Many swimming creatures like fish, dolphins and ichthyosaurs share the same basic “streamlined” body shape which minimises drag:
#Fish, Frank E. (2023): “Aquatic Locomotion: Environmental Constraints That Drive Convergent Evolution” Chapter 15 of “Convergent Evolution”
https://link.springer.com/chapter/10.1007/978-3-031-11441-0_15
Quote: “The quintessential example of evolutionary convergence is that between the shark, ichthyosaur, and dolphin. Although not closely related, the three exemplar taxa have independently evolved adaptations in morphology, physiology, and behavior that result in concomitant levels of performance that meet the requirements associated with operating in a dense, viscous, and thermally conductive marine environment. These apex marine predators display a remarkable amount of homoplasy. All three taxa have developed streamlined fusiform bodies to reduce drag when swimming.”
Other factors leading to the convergent evolution of swimming creatures include maximising thrust:
#Bale, Raul (2015): “Convergent Evolution of Mechanically Optimal Locomotion in Aquatic Invertebrates and Vertebrates” PLoS Biology, vol.13, 4
https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1002123
—Suddenly a patch of strangely looking leaves begins to move and wraps around a distracted grazer, dragging it down into hungry jaws. A predator that’s had eons to adapt its camouflage to fool its prey. But not only by imitating leaves – both hunter and prey never evolved eyes in this dark underwater murk. Instead, they battle with sounds and textures. Listen!
Some creatures give up their eyesight if they find themselves in a dark environment:
#Owen, James (2015): “How This Cave-Dwelling Fish Lost Its Eyes to Evolution” National Geographic
Some animals, like moths, use acoustic camouflage against hearing-reliant predators:
#Simon, Ralph; et al. (2023): “Acoustic camouflage increases with body size and changes with bat echolocation frequency range in a community of nocturnally active Lepidoptera” Journal of Animal Ecology, vol. 92, 12, 2363–2372
https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2656.14016
#Shah, Karina (2020): ”Earless moths have acoustic camouflage that protects them from bats” New Scientist
—There’s a whole cacophony down here. Countless species are singing to each other, sending warnings or invitations, forming a collective song. Like the noisy jungles of Earth, except Howler Monkeys and screaming pihas are replaced by chattering Seed-Eaters poking at the mud with snapping pincers, squeaking Spike-Bulbs loaded with poison and the flailing fins of starfish-shaped Grabbers hunting small prey. Beautiful and unsettling. In this stable and never changing ecosystem, their music will never end for billions of years.
The sounds of the jungle are not random! A recent field of study ‘ecoacoustics’ reveals the complexity and interactions between the sounds made by many species living together.
#Deichmann, Jessica L. et al.(2018): “It’s time to listen: there is much to be learned from the sounds of tropical ecosystems”, Biotropica, vol. 50, 5, 713–718
https://www.eva.mpg.de/documents/Wiley-Blackwell/Deichmann_Time_Biotropica_2018_2622796.pdf
Planets around Red Dwarf stars may have very stable and long-lived habitable surfaces.
#Gale, Joseph; Wandel, Amri (2017): “The Potential of Planets Orbiting Red Dwarf Stars to Support Oxygenic Photosynthesis and Complex Life”, International Journal of Astrobiology, 16, 1, 1-9
https://arxiv.org/pdf/1510.03484
Quote: “Calculations show that, depending on their mass, RDs could live over 100 billion years, much longer than the (current) age of the universe”
—You are immersed in the blinding light of the B-type star Caeruleus, shining hot and blue, orbited by a dozen lava planets burned to crisp. But we will visit the last planet: Nimbus, a gas giant very much like Neptune in size and composition – except there is a lot more water – and seething hot Caeruleus showers it with 900 times more light than Neptune. So its atmosphere is warm enough that gigantic white clouds the size of countries, are lofted by titanic warm updrafts rising from the hazy depths.
The Nimbus ecosystem is inspired in part by Carl Sagan’s work on possible ecologies floating in Jupiter.
#Sagan, Carl; Salpeter, Edwin E. (1976): “Particles, Environments, and Possible Ecologies in the Jovian Atmosphere” Astrophysical Journal Supplement Series, vol. 32, 737-755.
https://articles.adsabs.harvard.edu//full/1976ApJS...32..737S/0000737.000.html
B-type stars are blue, hot stars that are much brighter than our Sun.
#COSMOS - The SAO Encyclopedia of Astronomy: “Harvard’s Spectral Classification” (retrieved 2024)
https://astronomy.swin.edu.au/cosmos/*/Harvard+Spectral+Classification
#Morgan, Siobahn M.: “Spectral type characteristics” Astronomy course notes, University of Northern Iowa (retrieved 2024)
https://sites.uni.edu/morgans/astro/course/Notes/section2/spectralmasses.html
#Noll, Landon Curt (2022): “Stellar Classification Table - sorted by HR Class”
http://www.isthe.com/chongo/tech/astro/HR-temp-mass-table-byhrclass.html
If there's enough water and the star supplies sufficient energy, this might help create an habitable atmosphere, though many limitations exist.
#Seager, Sara et al. (2021): “Possibilities for an Aerial Biosphere in Temperate Sub Neptune-Sized Exoplanet Atmospheres”, Universe, vol.7, 6, 172
—Millions of years ago, and astonishingly quickly life emerged and evolved inside tiny water droplets deeper down in the planet. Like extremophile microbes on earth, they found ways of breathing methane and using exotic enzymes to harvest sulphur and nitrogen compounds from the air. As Caeruleus grew hotter and brighter, the higher altitudes of Nimbus became habitable and life spread. Let’s dive into the gigantic white clouds to meet it.
Neptune contains gases like H2S and CH4 , which serves as an inspiration for the atmosphere of Nimbus
#NASA: “Neptune Fact Sheet” (retrieved 2024)
https://nssdc.gsfc.nasa.gov/planetary/factsheet/neptunefact.html
#Irwin, Patrick G.J. et al. (2019): ”Probable detection of hydrogen sulphide (H2S) in Neptune’s atmosphere”, Icarus ,vol 321, 550-563
https://www.sciencedirect.com/science/article/abs/pii/S0019103518306109
These could be metabolised by extremophile organisms like those on Earth
#Brazelton, William J. (2006): “Methane- and Sulfur-Metabolizing Microbial Communities Dominate the Lost City Hydrothermal Field Ecosystem”, Applied and environmental microbiology, vol. 72, 9, 6257–6270
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1563643/
#Gwak, Joo-Han (2022): “Sulfur and methane oxidation by a single microorganism”, Proceedings of the National Academy of Sciences. vol. 119, 32
https://www.pnas.org/doi/10.1073/pnas.2114799119
Some energy generated by this process could be used to turn ambient ammonia into nitrate compounds to form proteins.
However, likely, oxygen is still needed in one form or another for organisms as complex and agile as we describe in this script
#Catling, David D. (2005): ”Why O2 Is Required by Complex Life on Habitable Planets and the Concept of Planetary “Oxygenation Time”” Astrobiology, vol.5, 3
https://faculty.washington.edu/dcatling/papers_mine/Catling2005-Astrobio.pdf
A partial solution could be achieved if these creatures use a slow methanotroph metabolism most of the time, and invest some of that energy to produce and store oxygen-rich compounds that they consume when they need to move quickly.
—Up here live quadrillions of tiny beings. A kind of cloud plankton so small they are carried on the gentlest air currents. The most common type resembles flat, four legged spiders barely a millimeter wide, tinted yellow by the sulfur they consume.
The inspiration for these creatures is phytoplankton that float on ocean currents.
#NASA Earth Observatory: “What are Phytoplankton?” (retrieved 2024) https://earthobservatory.nasa.gov/features/Phytoplankton
A small flat organism finds it much easier to float in air currents.
Many sulphur compounds are yellow
#MinDat: “Sulphur” (retrieved 2024)
https://www.mindat.org/min-3826.html
—They gain lift with wispy electrostatic threads, thinner than spider silk, pulling on the charge differences between the top and bottom of the cloud oceans. A technique Xysticus crab spiders use to travel great distances on Earth. You’re just in time for mating season. Billions of cloud plankton gather to join their threads into huge parachutes that ride updrafts for hundreds of kilometers. Here in the hot heights, they hatch their eggs before their life comes to an end. Other tiny creatures latch on, most of them predators looking to feast on fresh younglings.
Spiders can fly by exploiting the electric field present in the atmosphere.
#Berkowitz, Rachel (2022): “Airborne Spiders Drift on Multiple Silk Threads” APS Physics, vol.15, 31
https://physics.aps.org/articles/v15/31
#University of Bristol News and features (2018): “Spiders go ballooning on electric fields” https://www.bristol.ac.uk/news/2018/july/spiders-electric-fields-.html
Clouds can charge on Jupiter:
#Whitten, Robert C.; et al. (2007): ”Predictions of the electrical conductivity and charging of the cloud particles in Jupiter’s atmosphere” Journal of Geophysical research: Planets, vol. 113, E4
Plankton can reproduce sexually:
#MIZweb 2000/2004: “Reproduction in the plankton” (retrieved 2024)
https://depts.washington.edu/fhl/zoo432/plankton/plreproduction/reproduction.html
Spiders can congregate and weave together huge web mats:
#Greshko, Michael (2015):”Millions of Baby Spiders Create Giant Silken Blanket” National Geographic
—But not all life on Nimbus is tiny. The other way to stay up in the sky forever is to become a living balloon. Like the enormous Sky Whales, taller than a skyscraper, almost completely made of a wafer thin membrane. They heat up trapped gases, making them less dense than the air around them, giving them buoyancy. The bigger their gas envelope, the more lift it produces, so Sky Whales evolved to be as large as possible. Only a lumpy car-sized spherical bag of organs hangs at its bottom.
Hot air balloons make the air inside them less dense than the air outside, so they float via buoyancy.
Lighter-than-air vehicles like a hot air balloon perform better if they are larger, because of the way their lift-to-weight ratio scales.
The weight of a hot air balloon depends on its skin area, which scales with the square of size. A 10 times larger balloon is 100 times heavier. The lift comes from the volume of air inside, which scales with the cube of size. A 10 times larger balloon has 1000 times the volume and therefore 1000 times the lift. So, proportionally, a 10 times larger balloon has 1000/100: 10 times more lift to weight ratio.
—Heating up all this gas requires a lot of energy, so it is time to feed. The spherical body opens up, unfolding and lowering a huge sticky net into the white clouds. On earth the largest animals to ever exist, blue whales, feed by filtering millions of tiny krill each day. Similarly the sky whales of Nimbus filter sky plankton out of the clouds.
The largest animals in Earth’s oceans are filter-feeders:
#Schulman, Polly: ”How does a blue whale feed?” American Museum of Natural History: Giants of the Sea (retrieved 2024)
https://www.amnh.org/content/download/319438/4974264/file/part-3-text-passage-teacher-version.pdf
The Sky Whales here use a similar strategy. Their nets have to be very lightweight, so they give them a slight electrostatic charge that makes them sticky to their prey. That allows the nets to catch a much larger amount of food.
Electrostatic filters have been used to collect dust more effectively:
#Legg, Roger (2017): ”Air Conditioning System Design”
https://www.sciencedirect.com/topics/engineering/electrostatic-filter
—Most is consumed right away and burned in specialized glands to generate heat. The rest is converted into an orange and energy dense nectar for later.
The Sky Whales need to store energy between feeding times. On Earth, animals convert their food into fat, which is used later to produce energy. On Nimbus, the Sky Whales produce a nectar that’s highly enriched in sulfur. That sulfur can be reacted with the ambient hydrogen to produce hydrogen sulfide and release energy:
#NIST Chemistry WebBook: “Hydrogen sulfide” (retrieved 2024)
A sulfur-rich nectar could look yellow to orange, like sulphur minerals.
#MinDat: “Sulphur” (retrieved 2024)
https://www.mindat.org/min-3826.html
—This nectar is the most valuable resource on Nimbus. Numerous predators are looking for it, but none so hungrily as the frog sized Jet Squids, evolutionary cousins of the whales. Several of them trail each Sky Whale, waiting for it to be distracted or sleepy after a succulent meal. Jet Squids are far less efficient floaters. But they are able to superheat and expel gases in short bursts, like a rocket. Like vampiric hummingbirds, their long and pointy beaks try to pierce their prey and lap up some of the nectar inside.
Jet Squid are smaller than Sky Whales, so they have a worse lift-to-weight ratio, making them worse floaters.
Many animals on Earth use some form of jet propulsion on Earth. An example are squids that shoot out water and have even inspired new methods of jet propulsion
#Zhu, Quiang; Xiao, Quing (2022): “Physics and applications of squid-inspired jetting” Bioinspiration & Biomimetics, vol.17, 4
https://iopscience.iop.org/article/10.1088/1748-3190/ac6d37
Quote: “In the aquatic world jet propulsion is a highly successful locomotion method utilized by a variety of species. Among them cephalopods such as squids excel in their ability for high-speed swimming. This mechanism inspires the development of underwater locomotion techniques which are particularly useful in soft-bodied robots”
An even more vigorous reaction in the Bombardier beetle combines hydrogen peroxide and hydroquinone to create a spray of irritating chemicals to defend themselves with.
#Emily, Osterloff (2020): “Bombardier beetles and their caustic chemical cannon” Natural History Museum
https://www.nhm.ac.uk/discover/bombardier-beetles-and-their-caustic-chemical-cannon.html
The two concepts are combined here: the Jet Squids use a chemical reaction to produce a jet of hot air that they direct for thrust like a rocket.
Their feeding mechanism resembles that of a blood-sucking mosquitoes
#PBS (2016): “How Mosquitoes Use Six Needles to Suck Your Blood” (retrieved 2024) https://www.pbs.org/video/deep-look-mosquitoes/
—Unlike in the stable Eye Ipa, life on Nimbus is doomed. B Type stars like Caeruleus live for a few hundred million years at most and this time is coming to its end. Soon it will be burning through its fuel at an astounding rate and violently burn our gas giant. Life on Nimbus is only 600 million years old and has barely ten million years left.
The lifetime of a star depends on its mass
#Impey, Chris:”Main Sequence Lifetimes”, Teach Astronomy (retrieved 2024)
https://www.teachastronomy.com/textbook/Star-Birth-and-Death/Main-Sequence-Lifetimes/
Caeruleus’ main-sequence life is around 600 million years, which is in the expected range for a small B-type star:
t~1010/M2.5 => M=(1010/t)0.4=(1010/6.1×108)0.4~ 3 solar masses
#Morgan, Siobahn M.: Spectral type characteristics” Astronomy course notes, University of Northern Iowa (retrieved 2024)
https://sites.uni.edu/morgans/astro/course/Notes/section2/spectralmasses.html
—Orsted is a Y-class brown dwarf thirteen times more massive than Jupiter and with a magnetic field sixty times stronger. It belongs to yellow star Sturgeon, which is about to disappear behind Orsted’s shadow.
Y-class Brown Dwarfs are the coolest Brown Dwarfs
#COSMOS - The SAO Encyclopedia of Astronomy: “Brown Dwarf” (retrieved 2024)
https://astronomy.swin.edu.au/cosmos/B/Brown+Dwarf
#Hensley, Kerry (2023): ”Investigation of a Nearby, Cold, and Young Brown Dwarf” NOVA: Research highlights from the journals of the American Astronomical Society
https://aasnova.org/2023/11/29/investigation-of-a-nearby-cold-and-young-brown-dwarf/
Quote: “Brown dwarfs are assigned spectral types M, L, T, and Y, ranging from objects that just barely miss the mass cutoff to be able to fuse hydrogen into helium to those that overlap in mass with the largest planets. The coolest brown dwarfs, those in class Y, might have cloudy atmospheres similar to those of giant planets but easier to study; tiny, faint, and cool, planets are hard to pick out against the bright light of their host stars.”
Brown dwarfs can have very strong magnetic fields.
#Emspak, Jesse (2017): ”Brown dwarfs have strong magnetic fields just like real stars” New Scientist
#Reiners, Ansgar; Christensen, Ulrich A. (2010): ”A magnetic field evolution scenario for brown dwarfs and giant planets”, Astronomy & Astrophysics, vol. 522, A13
https://www.aanda.org/articles/aa/full_html/2010/14/aa14251-10/aa14251-10.html
https://arxiv.org/abs/1007.1514
The calculation of the magnetic field is made assuming that Orsted is around 109 years old, a comparable age to those of the planets in our solar system. This result could vary depending on its metallicity.
Some examples of Y-type brown dwarf and their masses:
#Legget; Sandy K.et al. (2017): “The Y-type Brown Dwarfs: Estimates of Mass and Age from New Astrometry, Homogenized Photometry, and Near-infrared Spectroscopy” The Astropysical Journal, vol. 842, 118
https://iopscience.iop.org/article/10.3847/1538-4357/aa6fb5
Sturgeon is a yellow dwarf star like our Sun.
#NASA: “Our Sun: Facts” (retrieved 2024)
https://science.nasa.gov/sun/facts/
Quote: “Our Sun is a 4.5 billion-year-old yellow dwarf star”
—But you are interested in Monnier, one of Orsted’s many moons. It should get as much sunlight as our Earth, but its 3 hour orbit around the brown dwarf means its days are extremely short. Gravity here is a mere 5% of Earth’s, so the moon can only hold onto a thin carbon dioxide atmosphere that doesn’t retain much heat. So, its average temperature is far below freezing.
Monnier has similar magnetic properties to Jupiter’s moon Io, but it orbits at the same orbital distance as Amalthea, and has approximately the size of Saturn’s Enceladus, though a much higher density.
#NASA: “Io: Facts” (retrieved 2024)
https://science.nasa.gov/jupiter/moons/io/facts/
#NASA: “Amalthea” (retrieved 2024)
https://science.nasa.gov/jupiter/moons/amalthea/
#NASA: “Encedalus” (retrieved 2024)
https://science.nasa.gov/saturn/moons/enceladus/
Since Orsted is thirteen times as heavy as Jupiter, using Kepler’s third law, we can calculate the period of Monnier from the orbital radius of Amalthea.
Monnier is as far as Earth from its star as Earth and their stars are similar, so it is irradiated more or less as much as Earth, but its atmosphere is thinner, making it colder.
At a 5% Earth’s gravity and the radius of Encedalus, the escape velocity is:
ve=sqrt(2gd)=sqrt(2×0.05×9.8×250,000)= 495 m/s
Which is slightly above CO2’s root mean square velocity even at Earth-like temperatures:
#Śmietańska, Joanna: “Root Mean Square Velocity Calculator” (used 2024)
https://www.omnicalculator.com/physics/root-mean-square-velocity
However, some amount of CO2 would need to be replenished for the atmosphere to stay stable and make up for the loss of CO2 particles at higher velocities, especially given the heating by ionization.
—As its cold night begins, a chill descends on Monnier and dry ice snows from the sky. A green, blue and red Aurora illuminates the landscape, made from star plasma caught in Orsted’s magnetic field and striking Monnier’s atmosphere.
Monnier’s interaction with Orsted is based on Io’s magnetic interaction with Jupiter.
#Schmidt , Carl et al. (2023): “Io's Optical Aurorae in Jupiter's Shadow”, The Planetary Science Journal, vol. 4
https://iopscience.iop.org/article/10.3847/PSJ/ac85b0
The color of an aurora depends on which gases are struck by the plasma. Though molecular CO2 shines mostly in the infrared, if there is enough electron radiation it can shine blue, or dissociate liberating oxygen ions that shine red and green:
#Baptista, Kim (2023): “ASU study: Satellite captures carbon dioxide aurora from space” Arizona State University News
https://news.asu.edu/20230619-asu-study-satellite-captures-carbon-dioxide-aurora-space
Quote: “High above the Earth, near 90 km, or ~56 miles, carbon dioxide becomes vibrationally excited during an aurora, emitting more infrared radiation than typically observed in the atmosphere.”
#NOAA: “Aurora Tutorial” (retrieved 2024)
https://www.swpc.noaa.gov/content/aurora-tutorial
Quote: “The most common auroral color is a pale green color at a wavelength of 557.7 nm. This is the result of atomic oxygen having been excited to the 1S, or singlet S, state. Another less common color is a deep red which is the result of atomic oxygen having been excited to the 1D, or singlet D, state. Other colors come from other molecules such as nitrogen.”
#Lilensten, Jean; et al. (2015): ”Prediction of blue, red and green aurorae at Mars”, Planetary and Space Science, vol. 115, 48-56
https://www.sciencedirect.com/science/article/abs/pii/S0032063315001300
Quote: “We show that the electron impact on CO2 produces strong emissions at 412 nm and 434 nm, i.e., in the blue part of the visible spectrum which are due to the CO2+(A) Fox–Duffendack–Barker bands. The modeling of the electron transport at Mars shows that these blue emissions as well as the emissions of the 630 nm (red) and 557.7 nm (green) lines of atomic oxygen may be observable several times during a solar cycle during strong solar events.”
—The Sturgeon system was born from a nebula saturated with metals, so iron and lead are abundant. In this frigid cold, chock-full of toxic minerals, life found unique ways to make the best of a bad situation: by using ammonia instead of water, which would freeze in the short nights. And by incorporating magnetised minerals and Orsted’s magnetic field into its biology. On Earth species like lobsters or bees have learnt to sense magnetic fields, but life on Monnier takes it to a whole other level.
Extraterrestrial life might use ammonia instead of water in freezing conditions.
#NASEM (2007): “Why Water? Toward More Exotic Habitats” Chapter in The Limits of Organic Life in Planetary Systems, COnsensus Study Report
https://nap.nationalacademies.org/read/11919/chapter/8
Multiple species on Earth have evolved magnetoreception.
#Nordmad, Gregory C.; Hochstoeger, Tobias; Keays, David A. (2017): “Magnetoreception—A sense without a receptor”, PLoS Biology, vol. 15, 10
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5695626/
#Ernst, David A.; Lohmann, Kenneth J. (2016): “Effect of magnetic pulses on Caribbean spiny lobsters: implications for magnetoreception”, Journal of Experimental Biology, vol 219, 12, 1827–1832
https://pubmed.ncbi.nlm.nih.gov/27045095/
#Liang, Chao-Hung (2016): “Magnetic Sensing through the Abdomen of the Honey bee” Scientific Reports, vol. 6, 1, 23657
https://www.nature.com/articles/srep23657
—As Sturgeon rises and its red rays filter through Orsted’s crescent, a yellow glow rushes over the horizon. The snowfall stops and temperatures quickly rise. The ground creaks and multi-colored liquids trickle out from fissures all around you: cryovolcanism just like on Jupiter’s moon Europa.
Some aspects of Monnier are based on Jupiter’s moon Io. Io’s atmosphere is known to freeze and collapse minutes after it enters Jupiter’s shadow, then sublimate back into being after it exits the shadow.
#Tsang, Constantine C.C. et al. (2016): “The collapse of Io's primary atmosphere in Jupiter eclipse”, Journal of Geophysical Research: Planets, vol.121, 8, 1400-1410
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016JE005025
Cryovolcanism is a feature of many moons of gas giants
#Fagents, Sarah A. et al. (2021): “Cryovolcanism” Chapter 5 in “Planetary Volcanism across the Solar System”
—Brittle-seeming bundles start to unspool and climb off the ground, towards the bright star. Like Arctic flowers on Earth sprouting in the short summer, these plants don’t have a minute of daytime to waste. Their blossoms are saturated with magnetic minerals, making use of the extreme magnetism and low gravity to levitate, reaching up to a kilometer into the sky. Extending the sunset for as long as possible. Hey, don’t touch them! With a loud crack, the skyflower detaches itself from the ground and drifts out of reach.
Arctic flowers endure harsh conditions and bloom rapidly once the conditions are right.
#University of Lapland, Arctic Center: “Blossoming Arctic” (retrieved 2024)
https://www.arcticcentre.org/EN/arcticregion/flora-fauna/Blossoming-Arctic
The flowers are using a weaker, biological version of our man-made magnetic levitation in a low gravity and low temperature environment.
#Chiang, Tai C. (2004): “Magnetic Levitation at Room Temperature” (retrieved 2024)
https://groups.mrl.illinois.edu/chiang/chiang/magnetic%20levitation.htm
—Suddenly you are surrounded. Hundreds of shiny critters zoom by. They look like ice-skating snails and can circle Monnier faster than the sunset. From their head they extend two long stalks that are electrically-conductive and merge up top. A magnetic kite that drags them along the surface at breathtaking speeds.The Skaters formed a symbiotic relationship with photosynthetic purple microorganisms that live in their shells. These biological solar panels produce sugars that they share with the skaters in exchange for continuous starlight. If the skaters ever stop they risk their partners to freeze and death by starvation.
The Skaters are an extreme version of Jack Sail-by-the-wind on Earth. Instead of a physical sail that’s pushed on by winds, they use magnetic kites that hatch a ride on Orsted’s magnetic field.
#OEL: “Jack Sail By The Wind (Velella velella)” (retrieved 2024)
https://www.eol.org/pages/46550209
#The Wildlife Trusts: “By-the-wind-sailor” (retrieved 2024)
https://www.wildlifetrusts.org/wildlife-explorer/marine/colonial-creatures/wind-sailor
Photosynthesising symbiosis is common in animals like sponges or sea anemones.
#Venn, Alexander A.; Loram, Jeannette E.; Douglas, Angela E. (2008): ”Photosynthetic symbioses in animals”, Journal of Experimental Botany, vol.59, 5, 1069–1080
https://academic.oup.com/jxb/article/59/5/1069/537020
—The harmonic scenery is violently interrupted as the ground splinters open and a spiked metal claw grabs a Skater and crushes it. It belongs to an animal that looks like a cross between a sea-lion and a beetle. As it devours its prey it gets covered in pink and sparkly fluids. These ambushers hide in the crystalline ground, spreading an array of electrically sensitive whiskers that they use to detect their prey and strike just as they zoom by. Like living landmines that could be buried everywhere.
The Ambushers are inspired by trap-door spiders.
#OEL: “Trap Door Spiders (Barychelidae)” (retrieved 2024)
https://www.eol.org/pages/8815
#Encyclopedia Britannica: ”Trap-door spider” (retrieved 2024)
https://www.britannica.com/animal/trap-door-spider
Magnetic triggers were used in naval mines.
#Goodeve, Peter J. (1999): “The German WWII Magnetic Mine”
https://www.chem.ucl.ac.uk/resources/history/people/goodeve_cf/magmine.html
Google Sites
Report abuse