Questions tagged [space]

The near-vacuum extending between the planets and stars, containing small amounts of gas and dust. Also called outer space to refer to the physical universe beyond the Earth's atmosphere.

The near-vacuum extending between the planets and stars, containing small amounts of gas and dust. Also called outer space to refer to the physical universe beyond the Earth's atmosphere.

Since the word space has many different meanings (e.g. it is a set in mathematics, e.g. vector space, manifold, etc.), the space tag should be substituted with better tags if possible. E.g.

  1. In case of a vacuum, use the tag instead.

  2. In case of a spaceships, use e.g. one of the , and tags.

  3. and so forth.

554 questions
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What is the possibility of a railgun assisted orbital launch?

Basic facts: The world's deepest mine is 2.4 miles deep. Railguns can acheive a muzzle velocity of a projectile on the order of 7.5 km/s. The Earth's escape velocity is 11.2 km/s. It seems to me that a railgun style launch device built into a deep…
33
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Does more light from Andromeda get scattered in the atmosphere than in the entire trip to Earth?

Fires have been burning here in Northern California. Today there was just a slight haze of smoke. The sun had a slight red hue to it. As expected the lower it got the redder it became. The blue light was filtered out by the earth’s atmosphere and…
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Why does it take so long to get to the ISS?

I don't understand why when first launched Space X's Dragon capsule had to orbit the Earth many times in order to match up with the ISS? Was this purely to match it's speed, or to get closer (as in altitude) to the ISS? In the stages when it gets to…
25
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8 answers

What grounds the difference between space and time?

We experience space and time very differently. From the point of view of physics, what fundamentally grounds this difference? Dimensionality (the fact that there are three spatial dimensions but only one temporal) surely cannot be sufficient, as…
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How does space affect the human body (no space suit, no space craft)

How does "outer space" affect the human body? Some movies show it as the body exploding, imploding or even freezing solid. I know space is essentially a vacuum with 0 pressure and the dispersion of energy makes it very cold. So are the predictions…
nopcorn
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What are the mechanics by which Time Dilation and Length Contraction occur?

What are the mechanics of time dilation and length contraction? Going beyond the mathematical equations involving light and the "speed limit of the universe", what is observed is merely a phenomenon and not a true explanation of why time dilates or…
23
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6 answers

What causes the permittivity and permeability of vacuum?

When light travels through a material, it gets "slowed down" (at least its net speed decreases). The atoms in the material "disturb" the light in some way which causes it to make stops on its path. This is expressed in the material's permittivity…
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What would actually happen to a person jettisoned into space?

Alright, so we have all seen the movies where someone gets blasted out of the airlock on their starship, or their suit decompresses while on a space walk. The poor schmoe usually either decompresses so violently that blood is oozing out of every…
Josh
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If space is a vacuum, how do stars form?

According to what I have read, stars are formed due to the accumulation of gas and dust, which collapses due to gravity and starts to form stars. But then, if space is a vacuum, what is that gas that gets accumulated?
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Why were space physicists wrong about the location of the heliopause?

The heliopause is now estimated to be something around 100 AU (1 AU = Astronomical unit = about the earth sun distance). See the wikipedia article: http://en.wikipedia.org/wiki/Heliosphere From reading a book on NASA's Voyager mission, I learned…
Carl Brannen
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If I take a bottle of air into space, and open it, where does it go?

It seems to me that space doesn't have any/much air, and if my bottle is full of air, when I open it, where does the air go?
Ted Wong
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Why are spacecraft made to "spin" after launch?

At some point after launch, usually just before or after separation from the last booster stage, spacecraft are often made to "spin" (about the axis of their trajectory)? See e.g this You Tube video. What is the reason for this spin?
17
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How vacuous is intergalactic space?

You often hear intergalactic space is an example for a very good vacuum. But how vacuos is space between galaxy clusters and inside a huge void structure? Are there papers quoting a measurement/approximation method (building the difference of a very…
Hauser
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What would happen to wet laundry in the vacuum of space?

Imagine for a second that I was in a college dorm room frustrated that all the dryers were broken or in use. I'm impatient and not a jerk so I don't wait or take out someone else's laundry, I shoot it into space with the ability to get it back and…
Throsby
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What is Space in Physics?

Is space a physical thing like matter? Is it a concrete thing or just an abstract concept?
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