User Carl Witthoft

27 votes

How many people are necessary to maintain modern civilisation?

answered Jun 17, 2019 at 18:18

15 votes

Is it possible for a planet to have the same seasons in both hemispheres?

climate weather worldbuilding-process seasons

answered May 21, 2020 at 14:20

13 votes

How to supply water to a coastal desert town with no rain and no freshwater aquifers?

technology water

answered Jul 2, 2019 at 17:31

12 votes

Biological refrigeration?

internal-consistency biology

answered Aug 26, 2019 at 19:06

12 votes

How Would I Make an Oceanless World Feasible?

internal-consistency planets climate weather habitability

answered Apr 2, 2020 at 17:31

11 votes

If you open a 1ft-diameter portal between Earth and space, how fast will the air rush through?

science-based space portal

answered Jun 30, 2021 at 12:29

10 votes

Why would a sleeper ship be designed to only wake one person in case of emergency?

space-travel colonization cryogenics

answered Apr 24, 2020 at 14:24

8 votes

How much volume does a liquefied human take?

biology mathematics

answered Apr 28, 2020 at 15:38

6 votes

The first McDonald's restaurant on Mars

economy food mars infrastructure

answered Oct 29, 2018 at 13:26

5 votes

Reality Check on Forest Placement

internal-consistency environment

answered Feb 5, 2020 at 16:20

5 votes

How Can An Alien Ship Harness Nuclear Energy?

underwater nuclear nuclear-power detection

answered May 12, 2020 at 13:47

5 votes

Shooting through the earth

weapons hard-science kinetic-weapons

answered May 20, 2020 at 13:17

4 votes

Anatomically Correct Creatures that can't be effectively dispatched with guns, but only swords, spears, clubs, quarterstaffs and their like

science-based creature-design

answered Jul 22, 2020 at 13:27

4 votes

Creating Darkness

science-based light

answered Jul 26, 2019 at 14:18

3 votes

How would a Grey Goo robot compute given that it has no fixed form?

science-based science-fiction computers nanotechnology

answered Feb 5, 2020 at 16:24

3 votes

Could somebody get temporarily stuck/“glued” to a wall by way of energy or some other force?

technology nanotechnology electromagnetism medical torture

answered Mar 5, 2020 at 16:03

3 votes

In what era or tech level in earth's history did people have the ability to cross a super-earth's ocean 50,000 km wide?

internal-consistency planets earth-like civilization

answered May 3, 2018 at 14:45

3 votes

Is acid blood possible?

biology evolution aliens blood natural-defenses

answered Jun 14, 2019 at 15:28

2 votes

Odd-Toed Ungulates

creature-design evolution xenobiology fauna

answered Jul 1, 2019 at 17:56

2 votes

How could polycephaly evolve as a byproduct of natural selection?

science-based internal-consistency creature-design evolution

answered Feb 8, 2018 at 18:54

2 votes

How would normal colors be affected if a planet's atmosphere was green?

science-based planets science-fiction atmosphere

answered Mar 5, 2020 at 16:13

2 votes

Underground Base

technology underground

answered Jul 17, 2019 at 17:50

2 votes

Designing a time thief proof safe

time-travel security

answered Sep 20, 2019 at 15:54

2 votes

Where do producers get nutrients in an airborne ecology?

biology flora

answered Jan 28, 2020 at 15:07

2 votes

What are the challenges in containing dangerous compounds?

physics

answered Mar 3, 2021 at 13:45

1 vote

Skysteading: How to build a flying city

internal-consistency physics construction

answered Jan 3, 2020 at 14:56

1 vote

A sound reason for vampires to be weak to sunlight?

science-based biochemistry vampires

answered Mar 24, 2020 at 17:09

1 vote

How does targeting teleportation work without a pad or something?

space-travel teleportation

answered Jul 12, 2019 at 14:59

1 vote

Firearm ammunition surviving 200 years

apocalypse firearms

answered Jun 14, 2019 at 15:23

0 votes

How could a tree survive a volcanic blast?

biology magic flora volcanoes

answered Jun 17, 2019 at 18:20

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51 Answers

How many people are necessary to maintain modern civilisation?

Is it possible for a planet to have the same seasons in both hemispheres?

How to supply water to a coastal desert town with no rain and no freshwater aquifers?

Biological refrigeration?

How Would I Make an Oceanless World Feasible?

If you open a 1ft-diameter portal between Earth and space, how fast will the air rush through?

Why would a sleeper ship be designed to only wake one person in case of emergency?

How much volume does a liquefied human take?

The first McDonald's restaurant on Mars

Reality Check on Forest Placement

How Can An Alien Ship Harness Nuclear Energy?

Shooting through the earth

Anatomically Correct Creatures that can't be effectively dispatched with guns, but only swords, spears, clubs, quarterstaffs and their like

Creating Darkness

How would a Grey Goo robot compute given that it has no fixed form?

Could somebody get temporarily stuck/“glued” to a wall by way of energy or some other force?

In what era or tech level in earth's history did people have the ability to cross a super-earth's ocean 50,000 km wide?

Is acid blood possible?

Odd-Toed Ungulates

How could polycephaly evolve as a byproduct of natural selection?

How would normal colors be affected if a planet's atmosphere was green?

Underground Base

Designing a time thief proof safe

Where do producers get nutrients in an airborne ecology?

What are the challenges in containing dangerous compounds?

Skysteading: How to build a flying city

A sound reason for vampires to be weak to sunlight?

How does targeting teleportation work without a pad or something?

Firearm ammunition surviving 200 years

How could a tree survive a volcanic blast?