Skip to main content

New answers tagged

2 votes

Negative pressure projectile propellants (Alternatives to gunpowder)

I'm going to throw science-based to the wind The only chemical I know of that absorbs oxygen (not air... oxygen) is pyrogallic acid. Compared to what you need to make a slug an effective bullet, it's ...
JBH's user avatar
  • 124k
4 votes

Negative pressure projectile propellants (Alternatives to gunpowder)

Using suction to "pull" the projectile has one major drawback: as you suck at the projectile, you are also sucking at the air outside the barrel with the same but opposite force. The air ...
Going Durden's user avatar
  • 3,626
5 votes

Negative pressure projectile propellants (Alternatives to gunpowder)

As stated by the other answers, vacuums are a bad idea. However, consider this answer a loose interpretation of your final sentence. A coilgun "sucks" metal projectiles forward out of the ...
David Robie's user avatar
7 votes

Negative pressure projectile propellants (Alternatives to gunpowder)

This - or something adjacent to this - has been done before. Ultimately, there's no reason not to use regular propellant. Normal things explode just fine, and if you have the tech to make something ...
controlgroup's user avatar
  • 4,676
25 votes

Negative pressure projectile propellants (Alternatives to gunpowder)

It sounds like a poorly conceived idea. Reason? With increasing pressure you can go up as much as you want, the limit being the strength of your barrel. If 20 bar of up pressure are not enough, you ...
L.Dutch's user avatar
  • 289k
2 votes
Accepted

How long would a stock of nuclear warheads and their delivery systems remain viable?

Maybe five years minimum At fifty years without a complete refurbishment they won't fire The EBW detonators have a shelf life of five years. Unless someone can make detonators to replace them, the ...
Thorne's user avatar
  • 46.9k
4 votes

Keeping an airship aloft using only propellers (and nuclear reactors)

Frame-ish Challenge So - in your question - you never specified how high up said vehicle was to travel. Which gives me a chance to talk about one of my favourite bits of Aviation lore: WIGs or as the ...
TheDemonLord's user avatar
  • 26.7k
5 votes

Keeping an airship aloft using only propellers (and nuclear reactors)

"Can you launch an ICBM horizontally?" "Sure, why would you want to?" (The Hunt for Red October) From a science-based perspective, yes, you can create the airship you're talking ...
JBH's user avatar
  • 124k
0 votes

Keeping an airship aloft using only propellers (and nuclear reactors)

Yes, it is 100% possible. However, there would be some questions about why not just use (non-flammable) helium bags to provide the lift, instead of expending massive amounts of energy on propellers to ...
Bubbles's user avatar
  • 839
0 votes

How to fight effectively on a space station

First of all: Air seals Air seals, that can divide the station in very small chunks, would reduce the danger of hull breaches from "everyone dies" to "a handfull of people die". ...
datacube's user avatar
  • 2,213
3 votes

How to fight effectively on a space station

The same way you would fight elsewhere A bit of a frame challenge. You have a giant space station. Not a tin-cans we use today, but a proper space station. With thousands of people living there. And ...
Negdo's user avatar
  • 2,323
7 votes

Keeping an airship aloft using only propellers (and nuclear reactors)

Have a look at the Convair NB-36H. This is 1950's technology. It had a nuclear reactor and propellors. One was not actually connected to the other but it could have been, and would have been if a ...
Richard Kirk's user avatar
  • 9,449
14 votes
Accepted

Keeping an airship aloft using only propellers (and nuclear reactors)

There aren't many Small Modular Reactor designs for which a mass has been given. One for which there is a mass figure is the Hyperion Power Module, which weighs 'less than 50 tons' and produces 25MW. ...
Monty Wild's user avatar
  • 61.8k
6 votes

Keeping an airship aloft using only propellers (and nuclear reactors)

Your propeller-airship is just a very large helicopter. So yes, it's possible, but just like with helicopters, it uses absurd amounts of energy to stay aloft. A side note: the suction on the top of ...
Burki's user avatar
  • 12.9k
1 vote

How to fight effectively on a space station

Foam Guns Globs of Neodyte Premium Bonder®, mixed in certain proportions with various other chemicals results in an air-drying foam. Just like flamethrowers, you can put the diluted Neodyte Premium ...
Blue Skin and Glowing Red Eyes's user avatar
1 vote

How to fight effectively on a space station

You fight like normal and patch things up afterwards. A bullet is not going to create a hole that that loses critical amounts of air during a the time frame of a normal fight. you are talking about a ...
John's user avatar
  • 81.4k
0 votes

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

Assuming this is in the current Earth scenario, there are a few possibilities I can see and it depends on how much time you wanna give to the population: Decades: it is a very bad luck scenario of a ...
Gio's user avatar
  • 1
0 votes

How to fight effectively on a space station

You watch the "ringing" of the station.. as in every time somebody moves about the station, impacting the wall, it changes the rotation, movement of the whole station, measurably. And if ...
Pica's user avatar
  • 4,558
5 votes

How to fight effectively on a space station

Why risk our guys at all? A space station is a hostile environment life-support system. All we need to do is reversibly break the life-support system and we win for free. Turn up the heat. 1: Wrap ...
g s's user avatar
  • 7,064
-1 votes

How to fight effectively on a space station

some options: first, a minor Frame Challenge: a space station is unlikely to have very heavy powered armor. Space is at premium at a station/spaceship, and every gram of weight had to be dragged out ...
Going Durden's user avatar
  • 3,626
1 vote

How to fight effectively on a space station

Smart fuzes Take a handheld grenade launcher, fit it with a computerized sight and laser rangefinder, and program the grenades to explode only if they did hit a target at the expected point of their ...
o.m.'s user avatar
  • 116k
1 vote

How to fight effectively on a space station

Energy Weapons Depending on the sort of tech you are dealing with in your universe, energy weapons are a good way to go. Personally, I normally shy away from energy weapons as they are almost entirely ...
TitaniumTurtle's user avatar
2 votes
Accepted

How to fight effectively on a space station

Self-Sealing Flechette. The thin, dart-like high-velocity projectiles with super hardened tips will punch through anything; armor, flesh, equipment and station alike. One won't do a huge amount of ...
Escaped dental patient.'s user avatar
0 votes

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

Starlink. Actually, more generally, the clouds of satellites we are putting in orbit these days. They're a royal pain for the astronomers and will make it harder to detect rocks. A bit of bad luck ...
Loren Pechtel's user avatar
1 vote

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

The object had a near-miss with the moon, and was pulled on to either a very different trajectory, or had been predicted to hit the moon, and didn't, again ending up on an Earth-intercepting ...
MikeB's user avatar
  • 111
2 votes

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

We Were Getting Our Rocks Off In a near future where humanity is experimenting with moving meteor fragments or high albedo debris around via drone "tugboats", we may end up cluttering up the ...
nullpointer's user avatar
  • 8,709
1 vote

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

Simple: You're looking for a needle in a haystack. How much stuff is in the sky in your solar system? Few objects? Easy to track and spot... Many? harder to spot. Many upon many? harder and harder to ...
WernerCD's user avatar
  • 1,735
1 vote
Accepted

What would be left after 150,000 years

Without knowing exactly what makes their building materials and architecture more durable than ours, the answer is probably still "pretty much nothing". Our technology won't last even half ...
talrnu's user avatar
  • 1,791
3 votes

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

This might seem simple, but it does explain the "Why did we not notice this ?" The asteroid is moving significantly faster than usual. (Maybe it's naturally accelerated, maybe it isn't, ...
Or4ng3h4t's user avatar
  • 372
9 votes

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

Really bad luck Estimates show that an asteroid in excess of 1 kilometer in diameter impacting Earth would be a civilization-kill event. While we have found over 90% of near earth 1-kilometer ...
Bubbles's user avatar
  • 839
14 votes

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

It could be an extra-solar object like 'Oumuamua. That would explain why it hadn't previously been detected. A sky survey might pick it up, but since it's heading almost directly towards us on a ...
N. Virgo's user avatar
  • 5,905
0 votes

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

There is a lot of research on this just now. Almost all money spent on space is wasted. We are not going to New Worlds, and bring back gold, tobacco, and slaves. However, spotting an earth-hitting ...
Richard Kirk's user avatar
  • 9,449
7 votes

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

Maybe it doesn't orbit; it's an interstellar object that strikes the Earth on the way through. We had our first recorded passage through the solar system of an interstellar object recently: https://en....
Robertiton's user avatar
21 votes

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

So a counterpoint to your view. The world thinks there is no warning system, not because it doesn't exist, but because the world has no way to respond to this information. A world ending meteorite ...
Flotolk's user avatar
  • 520
18 votes

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

The Asteroid was caused by the collision of 2 other asteroids that were not anticipated to hit earth So, there are two asteroids flying on a merry orbit, close-ish (in astronomical terms) to earth - ...
TheDemonLord's user avatar
  • 26.7k
29 votes
Accepted

Why wouldn't the world have advanced warning of a significant asteroid/comet strike?

The near-Earth objects we look for are mostly in the plane of the ecliptic, because that is where the vast majority of solar system material not in the Sun is to be found. The object that is about to ...
SoronelHaetir's user avatar
6 votes

How many people can China geographically support?

How many people can China support depends on the meaning of support. The People's Republic is the world's largest food importer; it imports food worth about 130 to 140 billion dollars per year. This ...
AlexP's user avatar
  • 90.4k
1 vote

How many people can China geographically support?

China still would need energy to create fertilizer via https://en.wikipedia.org/wiki/Haber_process to keep all those people fed and prevent instability. https://en.wikipedia.org/wiki/...
Pica's user avatar
  • 4,558
0 votes

With modern technology would it be possible to build an HG Wells style Martian tripod?

50/50 The problem is the energy source. In The War of the Worlds the tripods energy source is briefly discussed. Mostly in the context that research on it blew up two separate affords. Mechanically, ...
ErikHall's user avatar
  • 2,466
1 vote

Efficient method of storing energy in a near-future, semi-hard sci-fi game

An island-of-stability element is likely to have extremely high mass density, so just make the stuff so heavy and hard that it makes the general idea behind those ridiculous concrete-block-crane grid-...
Matthew Najmon's user avatar
0 votes

Why might physical media remain in use in a highly networked society?

Law Enforcement Needs (Wants) Hacker Grade Products There is a wide range of hardware out there that is specifically designed for footprinting and hacking. One product in particular that comes to ...
Nosajimiki's user avatar
  • 94.9k
11 votes
Accepted

Efficient method of storing energy in a near-future, semi-hard sci-fi game

Perhaps Pretorium has a stable nuclear isomer that can store a lot of energy for a long time, and is easy to trigger to release that energy, making it ideal to be used to make a nuclear battery If ...
Monty Wild's user avatar
  • 61.8k
1 vote

Why might physical media remain in use in a highly networked society?

“Never underestimate the bandwidth of a station wagon loaded with floppy disks racing down the highway.” — networking adage Portable media (probably a better term than physical media, which gets ...
SRM's user avatar
  • 25.5k
2 votes

Efficient method of storing energy in a near-future, semi-hard sci-fi game

Don’t store energy. Transmit it. Your petorium could provide a perfect receiver for laser-transmitted EM signals, so as long as your satellite/tower network is nearby, devices can operate. I think ...
SRM's user avatar
  • 25.5k
9 votes

Efficient method of storing energy in a near-future, semi-hard sci-fi game

Frame-challenge. This is a science-fiction answer to a science-based question. I wrote it that way because the constraints of the elements on the projected island of stability as science knows them ...
Escaped dental patient.'s user avatar
5 votes

Efficient method of storing energy in a near-future, semi-hard sci-fi game

So if the element was discovered in the future and it is on the island of stability, this element must have an atomic number above 119 and is a theoretical element. As stated the pretorium has a half-...
Khorzin's user avatar
  • 184
9 votes

With modern technology would it be possible to build an HG Wells style Martian tripod?

Probably Doable Currently the tallest robot built to date that walks on legs is an 18 meter tall, 25 ton, bipedal Gundam replica in Yokohama Japan. Although this robot is not quite as tall or heavy ...
Nosajimiki's user avatar
  • 94.9k
4 votes

With modern technology would it be possible to build an HG Wells style Martian tripod?

It wouldn't be possible with these specifications, but with some changes, it would be plausible There was a project similar to tripods in the 60s, the "Pedipulator", a machine that walked on ...
Khorzin's user avatar
  • 184
5 votes

With modern technology would it be possible to build an HG Wells style Martian tripod?

I think the tripods could work but they may be a bit different to the machines that are typically drawn on 'War of the Worlds' book covers. The robots in the MIT and Boston Dynamics labs are very ...
Richard Kirk's user avatar
  • 9,449
14 votes

With modern technology would it be possible to build an HG Wells style Martian tripod?

When it comes to 'possible', a War of the Worlds tripod should be achievable with near-future technology, pretty much just the R&D required to actually build the thing. While it wouldn't be the ...
Monty Wild's user avatar
  • 61.8k

Top 50 recent answers are included