Activity for Arkenstein XII‭

Type	On...	Excerpt	Status	Date
Question	—	Orange Suns and Blue Jupiters I am developing a fictional planetary system in which a large gas giant planet (slightly less than the mass of Saturn), has migrated into the habitable zone during the formational years of the system, and hosts habitable moons. The star in question is a K0V Orange Dwarf, which is reasonably quiet (i... (more)	—	almost 5 years ago
Answer	—	A: What kind of star will work for my system? For a star of that mass, you are looking at a G0V to F9V main sequence star. It's luminosity, depending on age, is probably around 1.2 sol, from which you can calculate the bounds of the habitable zone. The inner edge of the zone is around 1.04 AU. The comfortable outer limit is around 1.5 AU. The... (more)	—	about 5 years ago
Answer	—	A: What is my malfunctioning AI harvesting from humans? Brain and nervous system tissue Your AI has learnt to augment its silicon-based processors with human brain tissue, which it uses to undertake cognitive tasks that traditional computer processors are ill suited for. This allows the AI hunter units to be more independent of the central AI, and to ada... (more)	—	over 5 years ago
Answer	—	A: Conditions of a more ideal version of earth In astrobiology, this concept is known as the 'Superhabitable Planet'. Such a planet would be more massive than Earth, up to about 2.5 Earth masses. This additional mass provides shallower oceans, and lower topography. Additionally, it is likely that this feature will be paired with a thicker atmosp... (more)	—	over 5 years ago
Answer	—	A: In Search of a Super-Bright, Super-Stable Star The spectrum of a main-sequence star results mainly from the surface temperature, which is controlled by the star's mass. As mass increases, the star burns hotter, and as temperature increases, more of the stellar output is in higher wavelengths such as UV. The lifespan of these stars also results f... (more)	—	over 5 years ago
Answer	—	A: ''Habitable'' planet close to a star Models suggest that a desert planet (that is to say, a planet with some polar surface water, but otherwise dominated by land), can remain habitable as close as 0.75 AU from a star with luminosity of 1 Sol (Abe et al. 2011). This is only a touch further out than Venus's orbit, which has a semi-major a... (more)	—	over 5 years ago
Question	—	Which moon is most favourable as a refuelling station? My hypothetical gas giant has five major moons. Three of those moons are icy bodies with abundant water ice and volatiles. Any of these could provide fuel for translunar spacecraft, or for spacecraft headed further afield. However, not all of these moons are created equal. One of them is much deeper... (more)	—	over 5 years ago
Answer	—	A: What sort of qualities might a tortoise-like animal the size of an argentinosaurus need to support its own body? There are two good ways to have animals become larger. The first, is cooler temperatures. Animals tend to become bulkier with shorter limbs in order to conserve body heat, see: Bergmann & Allen's Rules. Bear in mind that cold-blooded organisms like tortoises may not be able to survive in colder cond... (more)	—	over 5 years ago
Answer	—	A: Can a liquid sand ocean exist naturally? Perhaps a vast colony of lithotrophic organisms lives deep beneath the sand? Long ago, the region was a rocky plain. Then, a species of lithotrophs was introduced, and they began to consume the very rock. The resulting by-products? Sand and oxygen rich gas. Over millions of years, the lithotroph co... (more)	—	over 5 years ago
Question	—	Visibility of a Red Dwarf Companion Star An interstellar traveller stands upon the surface of an alien planet beneath the light of an unfamiliar sun. The planet upon which he stands orbits one star of a binary system in which one is a G-class yellow dwarf and the other is an M-class red dwarf. While they are indeed orbiting their common ba... (more)	—	over 5 years ago
Question	—	Feasibility of an Antimatter-Catalysed Ram Augmented Interstellar Rocket (AC-RAIR) A fictional starship that I am designing functions via a form of Bussard ramjet that uses hydrogen from the interstellar medium as reaction mass, not as fuel. In order to accelerate the propellant, the starship utilises a fictional mechanism by which it is able to convert a fraction of the baryons e... (more)	—	almost 6 years ago
Question	—	Can Aspen forests have other species of tree present? In a world dominated by steppe, the warmest regions give way into parklands dominated by stands of Aspen. My research suggests that Aspen groves may tend to exclude other species of tree, but I am not sure whether this is the case. Having not visited such a place myself, I cannot draw from experienc... (more)	—	almost 6 years ago
Answer	—	A: Terraforming via rapidly growing organisms, is it a good idea? The creation of genetically engineered microorganisms for industrial and high-tech applications such as terraforming is certainly within the realm of possibility. However, there are several hurdles that they will face. First problem: The target planet needs to have an initial environment upon which ... (more)	—	almost 6 years ago
Question	—	How big is my Giant? The hero saves the captured giant, and as a reward, the giant presents the hero with a magic ring... However, the ring is made for giant fingers, so the hero decides to wear it as an armband instead. If the ring is a suitable size to be used as an armband, and assuming the giant has human proportion... (more)	—	almost 6 years ago
Answer	—	A: What does my dragon sound like? Your Dragons communicate largely using infrasound as a means to transmit across long distances. Similarly to Elephants, Hippopotamuses, Rhinoceroses, and even Alligators, these organisms find utility in the ability to communicate with others of their species over very long distances, especially give... (more)	—	almost 6 years ago
Answer	—	A: How difficult would it be to turn the Asteroid Belt into a single body? What's the best method? With sufficient effort, this could be done. It would require the manual alteration of the orbit of each asteroid. Bear in mind that the total mass of the asteroid belt is around 4% that of the moon, and that around half of that mass is already contributed by only 4 asteroids. The remainder are tiny ... (more)	—	almost 6 years ago
Answer	—	A: Desert planet with forests at the poles Earth-like Desert planets are entirely feasible. In fact, models have suggested that such a planet could enjoy a habitable zone that extends much closer to its host star than a more aqueous one could. Such a planet could be cold enough to possess ice-caps, but that will mean your deserts are also co... (more)	—	almost 6 years ago
Answer	—	A: How can a highly advanced sub-luminal galactic empire minimise the effects of speciation? One possible solution, is that your species have abandoned sexual reproduction entirely in favour of reproducing clonally. They are all derived from a database of genomes that were at some point in the past deemed to be the most satisfactory, and since then new individuals have been gestated in artif... (more)	—	almost 6 years ago
Answer	—	A: Could a terrestrial planet have water for a core? Water cannot remain fluid at the pressures of a terrestrial planet's core. However, it doesn't need to for your setting to be viable. The planet's crust could simply possess large, deep aquifers that provide water to oases. Some good examples of large aquifers beneath a desert are Australia's Great A... (more)	—	almost 6 years ago
Answer	—	A: How can a moon have an ever-changing face? The surface of the moon is covered in an exotic lifeform with an exceedingly rapid lifecycle. Colonies of this lifeform grow to cover large portions of the lunar surface in as little as 12 hours, competing for space with surrounding colonies, before rapidly crashing as soil fertility is depleted. No ... (more)	—	almost 6 years ago
Answer	—	A: Forging with geothermal heat: Possible alternative to fire in alien species' technological progression? The biggest impediment to metalworking without fire is getting the metal to forging temperature. Even the easiest to work metals, such as lead and tin, require temperatures around 300 C and 200 C respectively. These temperatures can be attained in a campfire, but geothermal steam of that temperature... (more)	—	almost 6 years ago
Answer	—	A: Is it harder for an intelligent octopus to live on land, or a human to live in space? One major advantage that octopodes have in colonising the land, is that they can already make short stints out of the water without any specialised equipment. This is very much not true of humans in a vacuum. A question asked on Biology SE details the ability of an octopus to survive out of water, a... (more)	—	almost 6 years ago
Answer	—	A: Could Multicellular Life Evolve Sans Cryogenian? The earliest Metazoa originate between 800mya and 750mya, so anywhere from 80my to 30my prior to the beginning of the Cryogenian. The occurrence of snowball periods is likely not a factor in their appearance. In fact, it has been suggested that the Cryogenian caused a loss of diverity in the Earth's... (more)	—	almost 6 years ago
Question	—	Tolerable range of surface gravities for interplanetary colonists? Human physiology is adapted for life at 1G, but planets colonised by future humans will likely have different surface gravities. What is the range of values for surface gravity that humans can comfortably tolerate long-term? Note: I am not interested in the absolute maximum gravity that a human cou... (more)	—	almost 6 years ago
Answer	—	A: How quickly would an ecocircle propogate over an unlimited flat world? Early microbial life on such a world is almost certainly aquatic, so I'll answer this question in those terms. Earthly bacteria move at a rate between 2 and 200 microns per second, with the higher speeds being attained by organisms with specialist adaptations such as flagella. The very first cells... (more)	—	almost 6 years ago
Question	—	Can giant planets in the habitable zone have rocky moons? My question is in the context of a fictional super-Neptune that lies in the habitable zone of its host star system. Giant planets only form beyond the Frost Line of their protoplanetary disk, and can then migrate inward to establish habitable orbits. Research that I have done on the topic suggests ... (more)	—	about 6 years ago
Answer	—	A: Population Growth of an Extraterrestrial Colony Ok, lets start with a population of 10,000 colonists. I will assume that the population consists entirely of adults that have been selected to be of reproductive age, and that half the population is female. Each woman will produce between 0 and 5 offspring. Assuming that they're voluntary colonists... (more)	—	about 6 years ago
Answer	—	A: How can spacecraft manufactured on the moon be powered? Straying slightly from currently available technologies to those that are possible, but not yet achieved... The Lunar surface is rich in Helium-3, so if Helium-3 fusion propulsion is developed, there is abundant fuel for it. https://www.esa.int/OurActivities/PreparingfortheFuture/SpaceforEarth/Ener... (more)	—	about 6 years ago
Answer	—	A: What is the minimum size for the Sun? The mass of a star is directly related to how hot its surface is, which in turn, is responsible for the wavelengths of light it emits (This is called Black-Body Radiation). As a main sequence G2V star, the sun has a surface temperature of 5778 K. A smaller main sequence star will be cooler and there... (more)	—	about 6 years ago
Answer	—	A: Question about climate and geography Ok, there are a few mechanisms that could allow your planet to have continents with reasonably uniform climate. Thicker Atmosphere The thicker the atmosphere of your world, the more heat will be distributed between the equator and the poles. There will still be temperature differences, but they wil... (more)	—	about 6 years ago
Answer	—	A: Would a geologically ancient world be habitable? If the planet has reached an age where internal heat is no longer sufficient to maintain active tectonics, it will enter what is known as a "Stagnant-lid Regime". One of the first things that happens at this point, is that the global carbon cycle grinds to a halt. Volcanism is severely reduced and u... (more)	—	about 6 years ago
Answer	—	A: Habitable zone around a Blue Supergiant Ok, so using Rigel as an example: Rigel has a luminosity of 120,000 sols, so for a planet to receive the same insolation as the Earth does around the sun, it would orbit at a distance of 346.4 AU. Given a stellar mass of 23 sols, and a planetary mass of 1 Earth, the year length is 1344.09 Earth yea... (more)	—	about 6 years ago
Answer	—	A: How might a group (with an electrical engineer) restore downed power lines post-apocalypse? One of the issues with doing this is that righting the pole is not enough. They're likely working with 11kV or even 33kV lines (depending on the country, but it'll be in this ballpark), which are under high tension. They would need not only to put the pole back up, but the re-tension the lines. Witho... (more)	—	about 6 years ago
Question	—	Making a Plague Worse? Starting in 541"“542 AD, the Plague of Justinian and a series of subsequent outbreaks killed between 13-26% of the world's population. The plagues were caused by Yersinia pestis, the same microorganism that would cause the Black Death in the 14th century. However, each subsequent outbreak during this... (more)	—	about 6 years ago
Question	—	Subtropical Ridges on a Cold Planet? I am working on the realism of a fictional planet which has an average temperature lower than that of the Last Glacial Maximum (LGM), and possesses a single large supercontinent rather than distributed landmasses. My research has indicated that Hadley Cells retreated equator-ward during the LGM, whi... (more)	—	about 6 years ago
Answer	—	A: How would you go about seeding oceans of Europa with adapted Earth life? The Earth has some excellent examples of ecosystems that thrive on the underside of sea-ice in the polar regions. Convection in the Europan ocean could conceivably bring nutrients up to the base of the glacial crust, which could be exploited by modified organisms that cling to the underside. https:/... (more)	—	about 6 years ago
Answer	—	A: What would shake a galaxy and what would shake the universe? Well, since vibrations can't propagate through a vacuum, the 'shaking' would have to be something that can propagate through spacetime. Something like a Gravitational Wave fits the bill. However, any event that would create a gravitational wave strong enough to shake a galaxy would probably also cre... (more)	—	about 6 years ago
Answer	—	A: What is a hypothetical, profitable way that the core of earth could be mined? Potentially the most cost effective way to mine the core of a rocky planet would be to first hit it very hard with something that removed the crust and mantle. Once exposed, the metallic core would be accessible to mining. However, it seems relatively counterproductive to do such a thing when the so... (more)	—	almost 7 years ago
Question	—	Desert Planet Realism - Minimum possible hydrosphere My question is fairly straightforward, but answering it is proving rather difficult. The scenario is on a planet with some water. The surface is dominated by deserts, both hot and cold depending on latitude. However, the atmosphere must be breathable by humans. So the question is: What is the minim... (more)	—	almost 7 years ago