81 questions with no upvoted or accepted answers
3k views

### How soon can the first stars form?

Introduction In our universe, the cosmic microwave background was formed approximately 400,000 years after the Big Bang. It was hot, but within a few million years after the Big Bang, it would no ...
244 views

### Weather with extreme seasons

Assuming the axial tilt of the Earth was increased to roughly 30°, and the orbital eccentricity roughly doubled(0.03 as opposed to 0.016) so that the average temperature stayed the same, but the ...
80 views

### Reasonable atmosphere for an Earth-like planet orbiting a K dwarf star (including abiotic oxygen)

I would like for my planet to be close to Earth’s size (so similar gravity), with much of the surface covered by water, containing atmospheric oxygen from abiotic processes (the photocatalytic ...
49 views

### What should an inactive planet's topology be for nutrient circulation?

I'm trying to engineer an Earth mass planet built initially out of pure silicon dioxide (silica). So basically, imagine a glass sphere slightly larger than Earth somewhere in the Goldilocks zone, ...
260 views

### How do I determine the physical size of a quartz crystal of a given shape and vibrational mode needed to approximate a specific resonant frequency?

So, one of my D&D characters has a cut/relief-carved quartz crystal amulet (medallion shaped) that's both an arcane focus (crystal) and a holy symbol (amulet), and I thought it would be a good ...
150 views

### How light can a quadruped's legs and relevant muscles be in proportion to their body without losing function?

Dragon? Only possible with Magic? No. Dragon: big, strong, hard-to-kill, flies. Marden: 25% of total mass IS dedicated to flight. Problem! Hard-to-kill? Small hitbox. All organs in ribcage, even a ...
93 views

### What blood pigment type is immune to ammonia poisoning?

I am designing a world in which the biological solvent is an ammonia-water mixture and need help finding out which blood pigments (Hemoglobin, Hemocyanin etc.) would be immune to the negative effects ...
118 views

### Is my topology/are my climate zones alright?

This is my first try at worldbuilding, and I need some feedback. I've filled in what I hope are realistic climate zones, ocean currents and topology for this current state of the world, all done in ...
142 views

### How would a K3 civilization collect the majority of the universes available mass in the form of Intracluster gas?

My story at its final stages is based around K3 civilizations whose technologies are within the known laws of physics and for plot reasons have managed to control all superclusters and lone galaxies ...
100 views

### In the orthogonal series, when finding the 4-force between two charges would the entire world line of each need to be taken into account?

Four-Velocity is the derivative of four-position with respect to proper time, four-acceleration is the derivative of four-velocity with respect to proper time, and four-force is equal to rest mass ...
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### Could a universe with 3 or more $U(1)$ charges that are all equivalent to each other be self consistent?

In alternate universe there are at least 3 $U(1)$ charges. An elementary fermion can have a value of $±1$, or $0$ for any of these types of charge. The value an elementary fermion has for one of ...
201 views

### Binary Star System Build - Alpha Centauri

I'm not sure if this site or Astronomy would be better, but I figured I would try here instead. I am attempting to create a [semi]plausible star system in Alpha Centauri for a series. The system was ...
204 views

### Spinning up the Moon: does it survive the event?

The year is 2xxx. A large asteroid is spotted on a collision course with Earth. The more time it passes, the more it is clear that the impact cannot be avoided. But when most of humanity is starting ...