Activity for Rúnatál Davino
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Question | — |
How to calculate hour angle of a moon? I am trying to construct a standing stone calendar for my world Jasmi, located at latitude 53.8 degrees South. To do this, I need the hour angle of moonrise and moonset for my world. The problem is that I have no idea how to calculate the hour angle of the Earth's moon, much less the hour angle of an... (more) |
— | over 6 years ago |
| Question | — |
How do I calculate solar altitude and hour angle from the surface of another planet? I'm trying to calculate the solar declination at the solstices, solar altitude at solar noon, and hour angles at sunrise and sunset to build a standing stone calendar at latitude 53.8 degrees South. Problem is: I have an axial tilt of 14.92 degrees, and I can't find any resources for calculating sol... (more) |
— | over 6 years ago |
| Question | — |
What rough climate and/or biome classifications would I assign to a planet with 31.1 degrees axial tilt? First, specifying format in this question I will be giving temperature ranges that sometimes appear backwards. This is because I am listing average temperature ranges from southern to northern latitudes. My landmasses are mostly located from the equator to the South pole. Therefore, my civilizations... (more) |
— | over 6 years ago |
| Question | — |
What vegetation/biome could I expect in a tropical region at an average temperature of 8-9 degrees Celsius? So, my climates are extreme due to a 31.1 degree axial tilt. The maps provided show a climate classification system based on prevailing winds and elevation. Based on Reddit user u/shagomir's Planet Calculator Pro workbook, I have an average temperature in the tropical regions of about 8.85 degrees C... (more) |
— | over 6 years ago |
| Question | — |
Given an initially high concentration of CO2 and H2O, how efficient can I conceivably make a photosynthetic reaction? I have been told that the high proportion of O2 and CH4 in my atmosphere are unsustainable unless constantly refreshed by an active process. I would like to sustain the following atmospheric composition: 75.11% N2 22.04% O2 1.38% CH4 0.83% Ne 0.21% CO2 0.18% Xe 0.11% Ar 0.09% Kr 0.04% He M... (more) |
— | over 6 years ago |
| Question | — |
Given atmospheric composition, density and scale height, planetary radius, and escape velocity, what is the lapse rate? My planet Mass = 0.602 MEarth Radius = 0.870 REarth Density = 5.04 g/cm3 vesc = 9.3 km/s Temperature = 272 K My atmosphere 74.84% N2 22.04% O2 1.38% CH4 1.25% Ar 0.27% H2O 0.11% CO2 Molecular mass = 28.88 Rspecific = 287.90 Density at sea level = 1.18 kg/m3 Pressure at sea level = 0.9... (more) |
— | over 6 years ago |
| Question | — |
How much gas can my planet retain in its atmosphere, based on its mass? My planet Jasmi is 0.602 MEarth and, according to the wonderful u/shagomir's Planet Calculator Pro spreadsheet, I need to retain enough gas for just over 5 atm of pressure at sea level for a suitable greenhouse effect for habitability. My atmospheric composition and pressure are as follows: 5.16 at... (more) |
— | almost 7 years ago |
| Question | — |
corrected projections: Is this world map realistic? I tried to use plate tectonics to inform my mountain and island chain placements 1 degree of latitude = 96.57 km. Equirectangular projections. (Yes, I need to revise the polar regions to make sure they don't get squished.) Obliquity of Jasmi: +31.1 degrees. Radius of Jasmi: 0.87 REarth Marked (too vaguely, I know,) are the equator, 31.1 degrees, 40 degrees and 58.9 degrees... (more) |
— | almost 7 years ago |
| Question | — |
What atmospheric composition do I need to sustain Earth-like temperatures at my planet's orbital distance; how close should my asteroid belt be? I need to heat my planet and I've decided that the two most plausible and controllable ways to do so are by increasing the amount of bombardment by meteoroids from a nearby asteroid belt, and by tinkering with the atmospheric composition. My planet is located 2.14 AU from a 1.71 LSol star, giving the... (more) |
— | almost 7 years ago |
| Question | — |
Is a snowball planet a necessary step in the evolution of a life-sustaining ocean planet? Still working on that world with with a 93% ocean covering. My star Xat is 1.71 LSol, and my planet Jasmi orbits at 2.14 AU. I've been warned that the resulting apparent brightness of about 37% Sol from Earth may halt my world's evolution at the dirty snowball stage; is this necessary? If so, is the... (more) |
— | almost 7 years ago |
| Question | — |
What is a plausible way to fuel highly active volcanism and seismic activity on my planet? I thought that a large, close moon might help generate enough heat and stress to raise the average temperature on my world and stave off a Snowball Earth scenario. According to this article and this article, I was incorrect. (Thanks very much for the help on that problem, though--I couldn't have done... (more) |
— | almost 7 years ago |
| Question | — |
Given an apparent solar brightness of <30% Sol from Earth, how differently would plants evolve? Though my star is 1.71 LSol, my planet orbits at about 2.14 AU. Following a back-of-the-envelope equation for apparent brightness, this gives the surface of my planet approximately 30% of Sol's light energy. It would actually be substantially less; my planet is extremely geologically and volcanically... (more) |
— | almost 7 years ago |
| Question | — |
Where to find equations to calculate tidal heating in a binary planet/planetesimal system? I'm building a very small homeworld (0.602 M$e$) with a very large moon (0.0711 M$e$) that orbit each other at a barycenter about 7.12 planetary radii (1 R = 0.870 R$e$) from the primary's center; 52.08 R from the moon's center. I'm trying to get a realistic model of geological activity on both world... (more) |
— | almost 7 years ago |