Score
Title
97
AskScience Panel of Scientists XVIII
553
AskScience AMA Series: I am Melinda Krahenbuhl and I am the director of the Reed Research Reactor, the only nuclear reactor operated primarily by undergraduate students. AMA!
10109
What elements are at genuine risk of running out and what are the implications of them running out?
278
Can you break sound barrier under water or any other material?
4029
What’s the largest star system in number of planets?
9
Does knowledge have mass? If so, how much does it weigh?
4
Does smoking THC extract or plant-based marijuana have long-term effects on memory?
5
We can see galaxies and some other objects that are millions or even billions of light years away, some of them might not exist anymore. How can we know or estimate if a star or a galaxy still exists?
18
Why does plastic turn white at the creases when folded/bent?
6
Are people taking immunosuppressant drugs, for example transplant recipients, less susceptible to autoimmune diseases?
3
How does radiation poisoning work?
6
When throwing stuff, does our brain actually try to calculate how hard it has to throw for the item to land at the desired point? Or does it just estimate based on experience?
5
How does thermal imaging work?
3
Could we make an artificial cell?
21
Do microwaves leave residual changes to molecules after heating?
3
Does the temperature have any (noticable) effect on air resistance?
3
What makes a given smell/taste "bad" or "good". Why do we interpret them one way or the other?
0
How do matches work? (The matches that generate fire obviously)
1
What happens to the jaw after permanent teeth grow in?
2
How is the height of the mountain measured?
0
How does mold grow inside ice machines?
4
Can a setup of hall engines provide enough thrust to keep a satellite stationary above earth?
3
What causes clothes to shrink in the dryer?
0
Is it possible for something underwater to catch on fire?
3
Why do mirages (ie. on a highway or desert) appear as specular reflections when the rough material they reflect off of should only produce diffuse reflections?
1
Why do joints like the wrists and ankles have a whole ton of bones, but joints like the shoulders only have two?
9
How does a memristor work?
3
When I move my phone left to right in a dark room while looking at this image, the text appears to jiggle back and forth like jello, or almost like a parallax. Why?
5
Do other species, animals, etc. experience the placebo effect?
2
What are the neurological or psychological differences between the auditory hallucinations of voices, e.g., as in schizophrenia, and a persistent negative internal monologue in one's own inner voice?
3
How do you measure the effectiveness of vaccines without a controlled experiment?
1
What makes the felid species "Neofelis" so distinct from others and a member of Pantherinae?
3831
What is the effect, positive or negative, of receiving multiple immunizations at the same time; such as when the military goes through "shot lines" to receive all deployment related vaccines?
1
Why did the “the Black Plague” and similar plague like events occur, some with massive impact, and why did they end?
2
I've read that when Betelgeuse explodes, it will create high levels of light at night for several days, but would a supernova on the "day side" of Earth even be visible at all?
2
Does listening to music or videos through headphones/earphones affect actual hearing after extended periods of use?
1
By what cycle do potholes develop?
4
If a planet had a radius that was equal to the altitude of Earth’s geosynchronous orbit, but had the same mass and rotational period as the Earth now, would there be reduced or zero gravity on the surface?
1
Does sound travel slower the deeper you are in water?
1
What is lost and what is preserved in a particle collider?
8
Why does snow melt in the sunlight, even when the temperature outside is below freezing?
14
Mar's summer temperature can be 20 celsius. Could a human survive with just an oxygen mask?
23 TheRealStardragon For a static situation that is interstellar and then intergalactic space. You'd have "a couple of atoms" per cubic metre. You might see pressures in the range of down to 10^-15 Pa. There might also be some dynamic situation (something moving very fast and as such leaving an area of very low pressure and particle density) where you get a very good vacuum for a very short amount of time in a small space.
6 mfb- The cosmic microwave background has about 400 photons per cubic centimeter, and that number is the same everywhere. The density of massive particles can be lower, but you never get completely empty space. Calling the space between particles a perfect vacuum is ... well, not really useful. Your places of perfect vacuum would change constantly or not be well-defined in the first place.
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26 0 TheRealStardragon For a static situation that is interstellar and then intergalactic space. You'd have "a couple of atoms" per cubic metre. You might see pressures in the range of down to 10^-15 Pa. There might also be some dynamic situation (something moving very fast and as such leaving an area of very low pressure and particle density) where you get a very good vacuum for a very short amount of time in a small space.
5 0 mfb- The cosmic microwave background has about 400 photons per cubic centimeter, and that number is the same everywhere. The density of massive particles can be lower, but you never get completely empty space. Calling the space between particles a perfect vacuum is ... well, not really useful. Your places of perfect vacuum would change constantly or not be well-defined in the first place.
4 0 [deleted] [removed]