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.
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Interstellar bodies
As a solar system evolves the planets interact, and in trying to achieve a harmonious state some bodies are ejected. Space is big, but I have heard that some meteorites have been found with anomalous ...
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Steady State Temperature of an Object Orbiting the Earth
This may be irrelevant or stupid to ask but I couldn't come up with a good answer. At least, we could not agree on with my friend the other day.
I would like an estimate of the temperature of a human ...
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Heat reflection on distant planets
I was watching a documentary last night on the first planet discovered outside our solar system.
The first one apparently is a giant gas planet that orbits very close to its sun over a very fast ...
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Does convection occur in microgravity due to pressure gradient?
Context:
On Earth, with gravity, when heating a fluid, the particles gain thermal energy and decrease in density, and a difference in density throughout the fluid causes thermal energy transfered by ...
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Does the sun's electromagnetic field disrupt communication?
If you were to design a drone or probe that could fly close enough to the sun to examine the corona, closer than the Parker Solar Probe, how close could you get and still have reliable communications ...
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Ice formation in a cavity that was sealed at ambient condition and taken to space
I have a hardware with a cavity that was closed (welded) at ambient conditions (298K, 1 bar Pressure and 50% RH). The hardware was taken to space where the temperature can go down to near zero Kelvin. ...
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Does the entire universe contain photons? [closed]
Since light travels in all directions, and since there is an infinite source of light in the universe, wouldn't that mean that ALL space within the universe must be filled with photons? (and that ...
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Can efficiency of fusor be improved by scaling up?
Fusors are very inefficient, among other reasons because the ions have to be decelerated and accelerated every time they fly out of the fusor, while radiating the energy out. However, what if we could ...
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the horizon of the planck volume?
Is there any helpful sense in considering the surface area around the Planck volume as a kind of extremely small horizon, similar to an event horizon or the much larger cosmic horizons in cosmology?
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air molecules in space
Just wondering about escaped stuff in space like air and water molecules. Where would those molecules ultimately end up going?
Considering that there is other gravitational forces in space like ...
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Would an Electron Gun create thrust in space?
Using solar panels, and the resulting electrical energy, could an electron gun provide a suitable level of renewable thrust, better than an Ion thruster? If it would even create thrust at all that is.
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Would the rotation of a space ship in vacuum slow it down
Firstly , a few disclaimers :
English is not my native language so I may use the wrong technical terms. Please notify me and I will correct the question.
As a CS major , I've only taken one class of ...
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What does it mean to say that "6 tons of dark energy would be found within the radius of Pluto's orbit"?
What does it mean to say that "6 tons of dark energy would be found within the radius of Pluto's orbit"?
Does it mean that the dark energy is orbiting the solar system?
Or does it mean a flow of dark ...
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How different sizes of water bubbles behaves in space
I watched a YouTube video of Chris Hadfield talking about different preventive measure for spills in space station. He is using water to demonstrate spills in space station. At 0.24sec the initially ...
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Is there, and if there is, what is the name of the concept that matter is made out of void/space?
I can't recall where I heard about this, but it was rather intriguing. I recall the notion that matter is compressed void/space, where I remember an example of a bedsheet representing space, and the ...
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What's wrong with this temperature-in-space calculation?
I'm trying to calculate the steady-state temperature of a body in space, but my numbers are coming up much too small. For example, for a 1-meter cube, I'm getting a temperature of 194 K (or -81 C). ...
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What will happen when Russia shuts down the GPS stations? [closed]
Russian officials are seriously talking about shutting down US GPS ground stations within their borders and Deputy Prime Minister of Russia tweeted on the subject.
What will happen to the GPS? My ...
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How far from a spacecraft would it's exhaust cool to BR temperatures?
Just a thought that came to mind ...
The rockets on interplanetary scouts fire to impart motive/braking force to the craft. This force, I understand, is simply a reaction engine - the exhaust ...
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How (if) can we connect a 2D "throat" piece of a wormhole to two hyperbolic 2D manifolds?
This question wad closed on the mathematics site, as it lacked clarity. So I try my luck here. My question is cosmology-inspired.
Imagine two 2D hyperbolic manifolds. I connect them by a manifold like ...
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A question about changes of the event horizon and the passage of time
If the event horizon of a blackhole doesn't experience the passage of time how can it change in size when it doesn't experience any time to do so?
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Is space not truly an empty vacuum but instead made up of densely packed particles of matter and antimatter?
In the livescience.com article Superpowered Chinese Lasers Could Soon Rip Open Raw Vacuum I read that quantum electrodynamics states that the vacuum of space isn't empty, rather it's made of densely ...
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How does the Giant Impact Hypothesis resolve impulse for orbital insertion?
The Giant Impact Hypothesis describes that Earth's moon was formed from collision between a proto-Earth and another Mars-sized object. This collision ejected mass from the Earth into orbit, whereupon ...
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How to find out diameter of some crater on moon using meteorite size and velocity?
I am looking for a formula to find out the diameter of a crater using meteorite size and velocity.
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Orbital period of a satellite in Kerbal Space Program
Let me start off by saying I am really bad at maths and physics, but lately I have been trying to calculate the orbital period of a satellite I have put in orbit around a planet called Kerbin in a ...
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Can you be your own space suit? [closed]
A few days ago a question was asked on Reddit whether or not a human could survive in space with "just enough" of a spacesuit to plug all the important holes, e.g. a face mask to plug the eyes, ears, ...
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Does laser beam expand along distance or not? [duplicate]
Why does laser dot become bigger at bigger distance?
e.g: from millimeter to inches so that it distracts pilots in aircrafts.
I knew that laser beam should't expand over distance, but remain stable. ...
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Does the microgravity environment in highly elliptical orbits differ from circular orbits?
I think everyone understands the microgravity environment broadcast from the ISS. But the ISS stays in a fairly circular orbit, the acceleration of gravity should be fairly uniform, the altitude and ...
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Why are heat-shields on re-entry vehicles smooth and not textured to increase drag?
Meteorites naturally texture themselves via the formation of regmaglypts, 'thumbprint-shaped' indentations caused by ablation of their surface, during entry into the atmosphere.
This appears to ...
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What is the true fundamental 'stuff' of physics? [closed]
It seems to me that most if not all of the publications and the institutional education of physics 'jump in' and start describing detailed phenomena without spending too much time describing and ...
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Laser divergence/convergence over large distance
I have hit a roadblock in my simulation, where there are 2 authors with contradicting equations on the model.
So I have simulated both, and drew it out for a few diameters. My dish size is 40m.
I am ...
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Dirichlet's work on gravity in non-Euclidean space?
In the book The Norton History of Astronomy and Cosmology by the late John North I have found the following statement (page 514):
"The German mathematician Lejeune Dirichlet studied the law of ...
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Videos of changing the orientation of an astronaut in space
Kane, Headrick and Yatteau describe in their paper "Experimental investigation of an astronaut maneuvering scheme" possible maneuvers to change the orientation in space without external torque. Is ...
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Why Can We See Stars In The Sky
Why is it when we look up into the night sky we can see stars. but when you see pictures taken from the ISS you don't see any stars. Why is this?
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What will happen if we put balloon in water tank in space
Imagine this. You have some object (let say barrel) and fill it with water. The water remains rather calm so it doesnt' spills out. Then we take a balloon filled with air and push it in that tank. ...
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What is the limit to how many satellites can orbit the earth?
I would like to know how many satellites are physically able to be in place, at the same time, orbiting the earth. Lets ignore which Nations need or use the most satellites (area in space above them) ...
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On constancy of cometary orbits
how are the comets able to keep to a nearly fixed orbital period, though they lose a certain amount of mass during their perihelion?
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Swimming in space
So we know you can't "swim" (or fly) in space as creatures can do on Earth, with no medium to push against, hence you need to expel something to get some propulsion.
But my question is about whether ...
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Red Photon Blue Photon
Why in space red light travels farther and is more observed in dying stars before a star becomes a black hole?
while on Earth in water and air the blue light travels the farthest. For example: a T.V....
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How is the temperature of a star related to gravity?
As far as I know the Sun gets its energy from the fusion reaction, where Hydrogen is converted into Helium.
I was watching an episode of Cosmos: A spacetime odyssey. There Neil deGrasse Tyson said,
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Is it possible to create nothing?
Is it possible to create nothing?
Lets say you take a cube serving only as a a shell. Then expanded the cube.
Or a balloon, the size of really really small. Then expanded the balloon using outside ...
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Get into orbit from the Redbull jump position to a satellite position by using a cord/rope?
Its difficult to put this into the title.
I was watching the Redbull Jump and noticed that the height of this is at 39 kilometres (24 mi) the atmosphere pressure is at I believe about 0.4% of that at ...
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Distance between molecules in outer space
I read that space has a pressure of about $1.322*10^{-11}$. I am curious to know how far apart molecules are from each other because of this extremely low pressure.
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Can neutrinos orbit galaxy centre like stars do?
I am layman in particle physics. I saw this question about gravitation affecting neutrinos. There is link to an article, but it is too difficult for me. Is it known if and where can neutrinos orbit ...
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Will an object released "upwards" from the ISS continue into the solar system?
Is it possible to release an object from a space station (say the ISS) to make it continue out into the solar system? The most intuitive answer to me (a non-physicist) would be yes, you are in space, ...
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Exerting force upon oneself in space
In space, there is no friction or forces of resistance of any kind, so I would assume that if two people were in space and one of them punched or pushed the other, the person upon which the force was ...
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How to calculate the pressure of a fluid when there is no gravity
Well for example we put a ball filled with water, with a density of $1\cdot 10^3 kg/m^3$, in space.
How to calculate the pressure the water is exposed to?
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If there's no atmosphere in space shielding from particles, why is not dangerous for spaceships/humans?
Some time ago I was thinking about this.
We know that space is almost matter-free, and also is plenty of particles and objects orbiting around all planets and sattellites. If objects orbit around ...
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Relativistic Jets in Black Holes
It is understood till now that nothing is faster than speed of light and we also know that even light cannot come out of black hole(that’s why the name black). So does that mean that the Relativistic ...
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Why is the transmission data rate between Mars and Earth so low?
I read that we get between 500 and 32k bits per second when sending data from Mars to Earth. Apparently it's substantially higher between Moon and Earth. What are the reasons? Please explain the ...
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Can a negative kinetic energy exist in a non-Euclidean space?
A particle with mass $m$ and velocity $\vec{V}$ has a kinetic energy $T=\frac{1}{2}mV^2$.
In an Euclidean space with Cartesian coordinates using Pythagoras theorem I can write the following
$$T=\frac{...
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