Posts tagged astronomy
I have a captured planet/moon orbiting HD 37124 c, known as HD 37124 c m XVIII, and I was wondering: since the moon has 1.7 Earth masses, 1.1 Earth radii, a density of 7.038 g/cm^3 and a gravitatio...
Globular clusters are old, dense groups of stars that tend to have relatively few metals (in this case meaning any elements heavier than helium). Clusters near the galactic core tend to have more m...
I'm creating a fictional planet that orbits a gas giant (a lot like Jupiter). I'm working out all the issues listed here and here. But what I'm really having trouble with is the size of the tide. ...
In my fictional world I have selected all parameters to maximize the Hills Sphere of my planet. The planet has three times Earth's mass and it is located in 2 AU from its star that's 1.4 times more...
Most of the planets that we know of have a sidereal day (rotational period) that is shorter or on the same order of magnitude as their sidereal year (orbital period), the latter being the case in t...
Basically I want to know what would happen to a planet if half of it was destroyed using explosives, does the answer depend on the size/gravity of the planet and what would be the result on the env...
In a few science-fiction books I've read, the world that the story takes place on doesn't have a sun, but does have a "sun belt," where (instead of a regular sun) the world is lit by a stretch of s...
Imagine a space cataclysm, where the Earth is hit by a deadly wave sterilizing all life of the bright side, but the dark side is more or less intact (at least the atmosphere and life are still in p...
Would it be possible to move Ganymede into Mars' orbit causing them to fuse together like the two proto moons of earth? The new planet "Marmede" would have a mass equal to 13.2 % of Earth. Ho...
Lets assume we humankind can not only wormhole the spacecraft, but planets and moons. So, what would've happened to Earth if we pulled Europa to be Mars's third moon? What if we moved Titan in betw...
So the design of the planetary system in the previous question goes on, following some of the precious suggestions and reference links, I somehow made the model work. I've been digging for similar ...
In the latest Artifexian video, he talked about terrestrial moons, bringing up great ways they could and would exist. But the video ended with an interesting concept, Horseshoe Habitable Moons. F...
Setting: Western world nation, Earth as we know it, May 2016, Gregorian calendar. Eccentric billionaire, large multinational corporation or similar; lots of money, and ability to enlist the help of...
There are plenty of threats out there that could terminate all life on our little planet in varying amounts of time (Solar flares, meteors and supernovas to name a few). Are there any disasters th...
I know that on a binary planet you would have planetary eclipses (basically like a solar or lunar eclipse but with planets instead of moons). If there also is a moon, things would be much more comp...
For those unfamiliar, An impact winter is a hypothesized period of prolonged cold weather due to the impact of a large asteroid or comet on the Earth's surface. (Wikipedia) In my world I want...
When I was observing the Moon yesterday, I asked myself: What would happen if a meteoroid impacted the Moon on the more clear part of the Moon which we can see, leaving a crater of the size like t...
I am working on a novel of a fantasy world on another planet. I am not too concerned with scientific accuracy, as again, it's fantasy, but I am not interested in supernatural things for my world. T...
Is there any software tool for quickly prototyping a planetary system? Ideally this should: Allow for placement of planets of different sizes and masses around a star. Allow for examination of th...
Consider a dual-star system, with the distances between S (larger star) and J (smaller star) similar to Sun"“Jupiter. A planet P rotates around J on a 90-degree ecliptic and is Earth-like otherwise...
It is estimated that in about five billion years, our sun will enter its red giant stage. During that phase it will expand and completely engulf Mercury, Venus and possible Earth. Earth will either...
Suppose there's a planet that has similar characteristics of Earth and can provide life, suddenly shatters in many pieces and scattered over the system. A small but very dense object is attached in...
Given Earth's current level of technology, space- and ground- based astronomical tools, etc., to what extent would it be possible to locate the Milky Way from a somewhat distant galaxy, say, in ano...
The Halo video game's extended universe book Halo: Evolutions describes the Battle of Psi Serpentis, in which a superjovian planet is converted into a brown dwarf via massive nuclear bombardment of...
The story begins in classic disaster film style. A small rogue black hole is approaching our Solar System. It isn't going to get close enough to destroy everything, but it will agitate our Sun, ca...
Let there be an earth-sized planet with a rotational period of just over 3 hours and 38 minutes described by David Hammen here . On this oblate spheroid, with nights lasting for an hour and 49ish m...
From Earth, we can detect extrasolar planets by a number of methods; primary are detecting the wobble in a star's motion caused by a large orbiting planet, and the dimming of the star's light as th...
EDIT: Question has been altered significantly in terms of design (originally having been a 'what-if'). This should (hopefully) accommodate more grounded and specific answers. Science often prefers...
Right now the Earth rotates around the y-axis so East and West replace one another. What would the affect be on Earth's seasons if it rotated on either other axis? The first is the Z axis, pointi...
Would it theoretically be possible for a solar eclipse to occur within a few days or even a few hours after a total lunar eclipse? The star, moon, and planet from which the event is being observed...
There is a system of one star and something like an asteroid belt around it. But the distance between asteroids is much less than usual, with some perhaps within nine kilometers of each other, and...
Say an early human civilization is arising on an earth-like planet (Earth, in fact) with one notable difference to the sky: a small ring of debris orbiting the planet. Assume the ring is clearly vi...
I want to have planet with as deep an ocean as plausibly possible. How deep can I go given these restrictions? Planet must be in habitable zone of a star Generally, planet should support life Siz...
I have two interstellar civilizations, both of which are extremely advanced and within a few thousand light years of earth. They go to war and make some stars explode in the process. The Combatan...
What would be the possible and definite effects of two galaxies colliding with each other? (Milky Way & Andromeda) Long-term and short-term effects are both important. I'd like to know becaus...
All life we know of to date (presumably) formed on a rocky planet (more precisely: earth). Fiction has been written about life in more exotic locations. Though as far as I know, these lifeforms wer...
A modern day Earth nation is at war with another. That other nation is extremely advanced but they are also pacifists. Instead of killing peoples their gun rounds and shells have the effect of worm...
Let's assume that a human colony was established on an exoplanet, dozens of light years from another inhabited planet, with the expectation that no one"”not even the colonists' far-future descendan...
Suppose we have a binary star system and a planet at the L4 or L5 point of the orbit of one of the stars around the other. The planet is thus illuminated by the two stars from the same distance and...
Are there realistic circumstances that a planet would be accelerated (either artificially or naturally) to the speed at which relic radiation becomes so blue-shifted that the planet is illuminated ...
I'm trying to picture life on a planet sized moon of a huge planet in a one-star stellar system. It would be tidally locked, which could do some interesting things. It has an iron/nickel core for t...
I'd like to be able to see from my Earth-like planet, a very bright nebula that can even be seen during the daytime. I question, however, whether that is possible, because in order for it to be co...
I've been imagining an RPG universe consisting of eight solar systems orbiting around a black hole in a finite universe with an edge, and I'm wondering what the night sky would look like to beings ...
I'm working on a bit of world building, and I was curious if it seemed to much more experienced worldbuders than I that including a collision with Halley's Comet in 1835 or 1910 as a major plot wo...
Background In my story, HD 28185 star system harbors life. One of them is an earthlike planet called Aucafidus, located at L4 of HD 28185 d (Subralis). In-universe, Subralis is white-blue in color...
Background In my story, HD 28185 star system harbors life. One of them is a jovian HD 28185 d (Subralis), located around 1AU of this sun-like star. In-universe, Subralis is approximately 132,000 k...
Note: I am aware of a previous question Physiological effects of living on a world close to a black hole As I understand it, that question refers specifically to a planet that is in a non-ideal ...
Setting: we have a fantasy world which is a planet with much of the same conditions that can be seen on Earth, but with the difference that it is orbited by a moon with a mean diameter of 3 500 km....
Time travel on movies and tv always say they were able to tell the year by looking at the stars. But how? For example Voyager goes back in 1996 and Ensign Kim says astrometrics puts them in the ye...
I found this on Wikipedia. I'm aiming for the fastest climate change possible without that much advanced notice, e.g. perhaps a regional sized asteroid scientists miss or are too distracted to cat...