Questions tagged [galactic]

For questions about galaxies (massive, gravitationally-bound groups of stars) or objects and systems that span a similarly large scale.

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9 answers
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How does an explorer civilization survive the Dark Forest Scenario?

The Dark Forest hypothesis is one put forth by author Liu Cixin in a novel named thus, which essentially revolves around three primary assumptions: There is life everywhere throughout the galaxy - ...
controlgroup's user avatar
  • 3,238
4 votes
2 answers
592 views

Would an increase in star density affect the "Goldilocks Zone"?

Let's say that there's a solar system that matches the description of Sol exactly, save for the fact that it's 20,000 light years closer/farther to the galactic center. Would the zone of one ...
Jarren_Takar's user avatar
14 votes
4 answers
3k views

How stable would a rogue star system be?

By some means, artificial or naturally occuring, a human inhabited star system has been flung from the Milky Way. Prior to being ejected from the galaxy, the system bears at least one Earth-like ...
WasatchWind's user avatar
  • 3,207
8 votes
3 answers
2k views

Detectability of a Type III Civilization with a specific set of conditions

Conditions: The civilization is in a galaxy which is not the Milky Way. For the purposes of this question, assume the target galaxy is 0.5 Mpc away. The civilization has elected, for whatever reason ...
JBH's user avatar
  • 122k
9 votes
8 answers
3k views

Stopping Milkdromeda, for Aesthetic Reasons

Basically, there is a human civilization controlling the milky-way and an alien civilization controlling Andromeda. They are communicating and have decided, for some reason, that, though the ...
skout's user avatar
  • 2,068
4 votes
2 answers
702 views

How Much of the Universe Could Humanity Conquer?

Imagine that less than a million years from now, probably in the hundreds of thousands, humanity has spread throughout the galaxy. There are afew aliens here and there, but that is insignificant, they ...
skout's user avatar
  • 2,068
4 votes
1 answer
185 views

Could machines survive in the galactic center?

Let's say a super advanced robot "species" that are programmed to roam the galaxy and explore. They build gigantic structures similar to Dyson spheres, and ensure that they will survive to ...
Mishima's user avatar
  • 999
14 votes
12 answers
3k views

How to map arms of the galaxy?

Some background: My interstellar civilization(s) have fled our home Solar System, spreading throughout the nearby systems in the Orion Arm. They possess FTL, but for plot reasons, they have only just ...
The Commander's user avatar
-3 votes
1 answer
125 views

How long would it take to run out of “space” in storytelling for an average sized galaxy? [closed]

I know that the average galaxy has over 400 billion stars and most stars have planets around it so it seems foolish to think the writers would ever run out of planets. It’s just for the suspension of ...
Max's user avatar
  • 61
-3 votes
2 answers
104 views

what cosmic event could teleport a solar system? [closed]

In a project I am mulling over, humanity now inhabits the dense core region of a globular cluster. They did not colonise this cluster; some cosmic event actually teleported the sun, moon and earth (...
user98816's user avatar
  • 8,583
2 votes
4 answers
235 views

What configuration should the worlds of a long lasting galactic empire take in the galaxy?

I have come across many galaxy maps showing the dominion/borders of one empire or another in different works of fiction. The first that comes to mind is WH40k for which the galaxy map of the different ...
Abanob Ebrahim's user avatar
6 votes
2 answers
140 views

How large can the main disk of spiral galaxies get? [closed]

I'm asking how large (by which specifically I mean diameter in light-years, though a rough estimate of the number of stars would be appreciated) can the main body of the spiral galaxy get. I'm ...
Ushumgallu's user avatar
8 votes
5 answers
531 views

Galactic 'geographic' features, how could they impact galactic colonization efforts?

I have been wondering how galactic features could impact interstellar civilizations in the process of colonizing a galaxy (either andromeda or the milky way). According to this video these features, ...
JuimyTheHyena's user avatar
9 votes
3 answers
962 views

Can a larger mass of stellar engines move a galaxy's dark matter?

There have been ideas about moving galaxies, if all of the needed stars and black holes become stellar/black hole engines but due to the 1:5 ratio of matter and dark matter there will not be enough ...
Alan Davies's user avatar
1 vote
1 answer
112 views

Could galactic tides power FTL travel?

I came across galactic tides while trying to find a new concept for FTL travel for a SF novel. Further research suggests it was just a coincidence, that nobody has ever suggested any possible ...
TheSpidermonkey22's user avatar
6 votes
2 answers
308 views

Conditions at the 10AU border of an Active Galactic Nucleus

Imagine that a ordinary human being was suddenly teleported to a distance 10AU from the center of the Milky Way. What would happen to them (in terms of things like pressure, temperature, radiation, ...
Saucy McBeef's user avatar
-1 votes
1 answer
137 views

How Would it Affect the Galactic Economy if One Planet Controlled 99%+ of the Galaxy's Gold and Silver? [closed]

The Planet Aurea has by far the most gold and silver out of any planet of the entire galaxy (thanks to two mountain ranges it has, one around the size of the US portion of the Rocky Mountains made ...
The Weasel Sagas's user avatar
3 votes
4 answers
353 views

How to Create the Galactic Habitable Zone

Our galaxy consists of a wide number of stars, anywhere from 100 to 400 billion stars, with just as many number of what are known as "habitable zones", in which liquid surface water is ...
JohnWDailey's user avatar
  • 14.6k
4 votes
2 answers
1k views

How do i make a galaxy map similiar to this?

https://i.stack.imgur.com/16dpM.jpg This is a star wars galaxy map i found. I have inkarnate but i dont think its possible to make a galaxy map like this on it.If anyone knows of any tutorials that ...
Shimmitar's user avatar
3 votes
2 answers
829 views

Is it possible for a future civilization to concentrate the galaxies (or some of them) of the universe?

In the world I describe there is not much time left before the expansion of space takes its toll. Galaxies are already accelerating away from each other on a negatively curved spacetime. The expansion ...
Deschele Schilder's user avatar
3 votes
2 answers
135 views

How Would An Advanced Alien Civilization Expand the Lifespans of Giant Stars (Nearly) Exponentially? [closed]

Long ago, in some distant galaxy, an advanced civilization had turned a small, young elliptical galaxy into their own astronomical playground. They seemed to have come up with a way to prolong ...
JohnWDailey's user avatar
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1 vote
2 answers
215 views

Does This Geopolitical Power Balance Make it Look Like I am Promoting Colonialism? [closed]

The book series I'm working on can basically be summed up as a science-fantasy series that starts out leaning much more on the fantasy end of the spectrum (the first few books could best be described ...
The Weasel Sagas's user avatar
2 votes
4 answers
449 views

How Would a Rising Power Escape the Attention of an Existing Superpower?

At the time my book series starts, the western half of the galaxy, regarded as a rural backwater with only one inhabited star system, is undergoing a complete transformation right under the nose of ...
The Weasel Sagas's user avatar
3 votes
3 answers
776 views

How to calculate the time on planet B for an event that happened on planet A?

We have had a number of "universal time" questions on this site — basically the various OPs have been looking for a way to establish a single time reference for the galaxy. I believe that's ...
JBH's user avatar
  • 122k
6 votes
2 answers
167 views

Life and Galactic Age: What galactic ages make a planet habitable?

How old does a galaxy need to be to harbor life for prolonged periods of time? Our galaxy was 8 or 9 billion years old by the time life emerged on Earth, so the lower boundary must be younger than ...
Nip Dip's user avatar
  • 507
6 votes
1 answer
252 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 ...
user avatar
2 votes
2 answers
226 views

How many Ultra massive black holes should be added to a map of known black holes?

I was wondering how many Ultra-massive black holes can be added to the list of 8 known black holes with mass over 10 billion solar masses within 1 billion light years. Looking at our current maps, the ...
user avatar
6 votes
2 answers
401 views

How could a galaxy be altered to house hundreds of thousands times more Stars?

It has been said that humans are capable of reaching up to a billion light years away before expansion has taken those galaxies permanently out of reach without FTL methods. I aim to have a ...
user avatar
9 votes
4 answers
2k views

Which type of star would be best used for a Shkadov thruster to reach Andromeda as soon as possible?

I had Originally thought of using Nicoll-Dyson beams to propel probes and small ships from the Milky Way to as many galaxies as they can reach to turn stars in those galaxies into Shkadov thrusters to ...
user avatar
2 votes
3 answers
269 views

Can a galaxy be formed from a black hole?

I'm writing creative text and I'm curious to know, just as possibility, can a galaxy by any chance be formed out of a black hole?
01e5Dk's user avatar
  • 131
2 votes
2 answers
379 views

Could a galaxy of Nicoll-Dyson beams hit a single target?

This was an idea for a flashback as I pick up my story around 100 trillions years from now at the point where star formation is ceasing and the red dwarf and stellar remnant era begins. Now living in ...
user avatar
4 votes
1 answer
205 views

How far above the galactic plane could an Earth-like planet develop?

I was zooming around on Space Engine and came across the moon of a gas giant that was hovering well above the galactic plane. I'm admittedly not well-versed in under what conditions an Earth-like ...
Vigilant's user avatar
  • 1,659
10 votes
1 answer
1k views

What percentage of stars would need to become Shkadov thrusters to move the whole galaxy?

The advanced civilization in my story is trying to reach as many galaxies as possible in the next few billions years before the expansion of space has sent those galaxies permanently out of reach ...
user avatar
7 votes
2 answers
525 views

Could habitable planets form in an ultracompact galaxy?

I am wondering if habitable planets could form around stars in super dense dwarf galaxies. There are some super dense galaxies such as M60-UCD1 and M85-HCC1 which can have a typical distance between ...
user avatar
4 votes
2 answers
297 views

What would the sky view be like of a final stage massive merged galaxy?

What will be the view of the sky and the distances between stars, living on a planet or in a habitat in a super galaxy that has merged with all its nearby galaxies in its cluster, at a time in the ...
user avatar
1 vote
1 answer
167 views

What would the view from a spaceship traveling through inter-galactic space look like?

My character is traveling aboard a spaceship through inter-galactic space (it has left the Milky Way). The ship is traveling at the speed of light or so and has been for the last six thousand years. ...
marmel's user avatar
  • 824
13 votes
3 answers
460 views

What would the geologic record look like on a planet in the galactic halo?

Imagine an Earth-like planet orbiting a Sun-like star in the inner halo of the Milky Way. As a halo star, it will likely be somewhat metal-poor, having formed early in the life of the galaxy, but ...
HDE 226868's user avatar
  • 101k
8 votes
2 answers
263 views

Randomly generating plausible star types for a synthetic galaxy?

I'd like to randomly generate between 1 and 20 million stars for a spiral galaxy resembling our Milky Way. This is of course far fewer than our galaxy (estimated between 150 to 300 billion), but I'd ...
John O's user avatar
  • 12.1k
1 vote
3 answers
409 views

How long would it take to conquer a galaxy? [closed]

I will explain this as briefly as I can. I'm thinking about beginning a novel that has an MC that is born into a race of super-efficient alien invaders. They're able to take over entire planets ...
RE Lavender's user avatar
5 votes
7 answers
1k views

Universal calendar creation for intergalactic empire [duplicate]

In my novel, I have created an intergalactic empire that predates humanity by millions of years. The only system I am having a difficult time creating, for this empire, is a Calendar system that ...
Richard LaBrie's user avatar
2 votes
5 answers
608 views

Minimum speed required for a galaxy spanning empire

The dawn of the Galactic Empire! Assume that FTL travel and communication is possible, for simplicity we say c is the speed of light. Assume any speed of travel and communication < c*2^100 is ...
user avatar
6 votes
11 answers
692 views

What type of natural or artificial disaster could devastate a multi galactic civilization?

There is an advanced civilization that spans multiple galaxies. The civilization has learned to tap every available source of energy within the volume that it has colonized. The civilization ...
Anders Gustafson's user avatar
1 vote
4 answers
269 views

What is the "fullest" the universe could be in terms of living space? [closed]

Lets take a civilization that has surpassed the type III on the Kardashev scale. It has the following assumptions: It harnesses the energy of entire Galaxies, its populace did not transcend. If you ...
Demigan's user avatar
  • 45.4k
65 votes
24 answers
13k views

How could a planet have a sky without stars at night?

Is it possible for a planet in our part of the galaxy to have a night without stars? I'm looking for some kind of natural phenomena that would hide the stars, but allow the sun to rise and fall as ...
Reactgular's user avatar
  • 2,385
14 votes
3 answers
1k views

What would the night sky look like for a world on the upper plane of the galaxy, near its rim?

I would like to include a world in a story that is located on the upper plane (or bottom, doesn't matter, but call it upper for the sake of reference) of the galaxy. If you think of the galaxy as a ...
JBH's user avatar
  • 122k
5 votes
6 answers
1k views

How could someone ground a breathable synthetic atmosphere onto a small asteroid?

Let's say there are billions of asteroids in the galaxy, varying in size from baseballs to hunks of rock almost big enough to be dwarf planets. If someone wanted to set up a habitable location on one ...
The Weasel Sagas's user avatar
0 votes
4 answers
457 views

How well would a society 35,000 years in the future remember today? [closed]

The story is set 35,000 years after the year 2024. In 2024, Donald Trump makes fun of Kim Jong Un's stupid hair, and long story short, the Earth gets nuked to the point where everything is covered in ...
The Weasel Sagas's user avatar
1 vote
4 answers
729 views

What kind of fuel would spaceships capable of faster-than-light travel use? [closed]

In my book series, faster-than-light travel is a thing, allowing the fastest spaceships to cross a Milky-Way-sized galaxy in a matter of days. The slower ships could manage that in about 2 weeks. ...
The Weasel Sagas's user avatar
0 votes
1 answer
96 views

Could a loose galactic alliance be dismantled in a quick coup? [closed]

In my book series (link here), the planets of Aurea, Ishgabangaloodoo, and most of the eastern half of the galaxy have entered an alliance against the Tatian Empire (Caput Tatiium and most of the ...
The Weasel Sagas's user avatar
0 votes
4 answers
500 views

What would an artificial galaxy look like? [closed]

Suppose there is an advanced type 3 civilization that has the capability of creating entire artificial galaxies (this means they can create stars, planets or even black holes). But how exactly would ...
ΓΙΑΝΝΗΣ ΜΙΧΑΗΛΙΔΗΣ's user avatar