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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Why is space having no atmosphere a good explanation for the Olber's paradox? [duplicate]
why is space dark? that is because there is no atmosphere to scatter the light.
why are we pretending that if we have had enough visible light from all those distant start, the space would light up. i ...
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How was this image of the faculae in the Occator crater obtained?
The picture in question (that I'm asking about) is at the bottom, of this post. Now, did they simply take a picture with reduced light intake? If so how much? 1/2, 1/4 or 1/8 or less? Or did they ...
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Asteroid in Deep Space 🌌
Suppose a asteroid in deep space and there is nothing around it to compare it with.
My question is how would you known that the asteroid is moving if there is nothing to compare it with
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How can Aggregation of Gravitational Fields of subplanetary solar objects improve our understanding of the motion of the planets?
If we imagine magnets on a table as a simplified analogy in regards to gravitational attraction between objects, then it may be demonstrated that when three objects are placed in a row labeled in ...
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Seeking Guidance & Tips for Collaboration on a Cosmological Project Involving Potential Energy Variation Due to Cosmic Expansion
I'm a student with a deep interest in cosmology and astrophysics. I've embarked on a project and am seeking some guidance, insights, or even ways that I could look for possible collaboration on this ...
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Which coordinate system should one use for simulating a spacecraft trajectory to the moon? [closed]
Which coordinate system is most suited for this type of problem? ecliptic? equatorial?
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Could the redshift of all incoming photons be explained by a massive ring of distant masses pulling the sources of the photons away?
ChatGPT and wikipedia have informed me that the primary evidence for the theory that the universe is expanding is the fact that photons that arrive to our planet from all directions are being ...
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Non-homogeneous and anisotropic metric and laws of physics...?
In this popular science article, they say that if our universe resulted to be non-uniform (that is highly anisotropic and inhomogeneous) then the fundamental laws of physics could change from place to ...
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Spacetimes where symmetries vary from place to place?
Are there spacetimes or metrics where symmetries (like Poincaré, Lorentz, diffeomorphism, translational... invariances) are only local and the symmetries of one local neighbourhood are not, a priori, ...
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Motion equation of a space engine in low-earth orbit
My goal is to simulate the movement/motion of a space capsule from low-Earth orbit with initial conditions emulating an initial thrust. Here is the code, Is it right? I know that the next step is to ...
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How to call the fear of no gravity? [closed]
In opposite to barophobia I can't google out a fear of the case, when a man is taken out of the ship and he must go through the spaceship's docks and he can't get the direction of gravity - in the ...
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can we fly a rocket past the black hole in the milky way? [closed]
Some information needed is facts about the black hole in a milky way.
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Why is time not a spatial dimension? [closed]
I am a little confused about dimensions.
People say we have three spatial dimensions and one temporal dimension but I don't know how this is possible. How can there be different "types" of ...
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What is the elemental composition of the universe?
What is the current distribution of elements in the observable universe? Wikipedia lists the composition of the Milky Way, but I'm not sure how the values would change if intergalactic medium were ...
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Could an object enter or leave the vicinity of the Earth without being detected?
I am aware of (but not really knowledgeable about) radar and visible device networks that monitor/track asteroids, satellites, space debris, and monitor the world for rocket launches for defense ...
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Are there any binary red supergiants?
I wonder if we ever have identified or observed a pair of binary stars (red supergiants). And I also wonder what would happen if they exploded, (theoretically) as we haven’t observed it. Also, would ...
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Is space really empty?
So I have been thinking about this question for like five minutes. Is ‘space’ really empty? I know that technically there aren’t atoms in deep space and that would make it empty, but there has to be ...
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What does it mean to be looking at something that is 13.5 billion years old? [duplicate]
Reading up on the James Webb telescope and how the images from it show us the universe as it was 13.5 billion years ago has made me wonder what does this mean?
Are we in essence viewing the past? And ...
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If Looking Into Space is Like Looking Back in Time, Why is it the Same in Every Direction?
After seeing the James Webb space picture, in which a tiny sliver of the sky the size of a piece of rice from our perspective here on Earth was examined and revealed contain, as expected, an abundance ...
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If the universe is a closed spacetime structure, can we assign a center of mass to it?
If we envision the universe like a balloon but in 3D, is it possible, in general, to assign a of global center of mass?
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Why not build a swarm of space telescopes?
James Webb Space Telescope (JWST) has not yet started doing science, yet its successor LUVOIR is being discussed already. However I am curious; some countries have invested billions of dollars in ...
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Will Jupiter's days speed up?
Jupiter has so many moons, and those moons have a gravitational pull on it. Does that mean, that over time, the length of Jupiter's days will get shorter?
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How to choose eyepieces and other accessories for a Celestron 70mm f/5.7 portable refractor?
I have a Celestron Specialty Series Travel Scope 70mm refractor which came with 10mm (40x) and 20mm (20x) eyepieces.
Specifications:
Focal ratio: f/5.71
Optical Design: Refractor
Aperture (mm): 70 mm
...
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Horizontal and equatorial coordinate systems
What is the difference between horizontal and equatorial coordinate systems apart from the notations (azimuth, altitude) and (right ascension and declination angle)? Please provide some measurements ...
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How will be changed Hill's radius and Kepler's formulas in case of 2D space instead of 3D?
Imagine that Flatland habitats go into space. All stars and planets are the circles instead of spheres and gravity law is $F=Gm_1m_2/R$ instead of $F=Gm_1m_2/R^2$.
How the other formulas will be ...
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What is the concept of wormholes? [duplicate]
My main queries for now I guess: What is the theory behind wormholes? What is the possibility and likeliness of their existence based on scientific analysis, not conspiracy theories? What is the ...
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Not getting quality images in telescope
I have a Newtonian telescope (Celestron 130 eq) with 5.2 inch (~132 mm) aperture with 650 mm focal length, Spherical mirror. And having 4mm, 10mm, 12.5mm, 20mm,20mm (erecting eyepiece), a 3x and 1.5x ...
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Because the Universe is expanding, what is it taking up?
It is my understanding that the universe is expanding and that matter takes up space. While the universe only contains small percent of matter, wouldn't expansion indicate that the universe is ...
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Weight of a gas measured in Space and other planets of Solar System
I searched for how measure gas weight and about gases in space
https://www.shutterstock.com/search/space+gases
https://education.seattlepi.com/gases-found-outer-space-5888.html
Will the weight of gas ...
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Can two neighboring galaxies move apart at steady speed?
While I was trying to understand the three models that obey Friedmann's two assumptions of a non-static universe, I came across a line that says and I quote "It (referring to Big Bang) starts at ...
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Could liquid water have existed in open space 15 million years after the Big Bang?
Around 15 million years after the Big Bang, the ambient temperatures was about $24^\circ {\rm C}$, which is in a range where water could be liquid. Could liquid blobs of water be existent then?
PS: I ...
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How do we know that spacetime is fabric? [closed]
I have started learning about astronomy as it amazes and inspires me.
I have a question. What led us to believe that spacetime is fabric? What is the evidence shows this, and is it considered proven?
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Density of stars on celestial sphere
The pattern of stars on the surface of the celestial sphere seems perceptually to have an universally looking structure. If you pick a region of the sky at random, for instance by using the (excellent)...
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Why do people say travelling at the speed of light or faster is impossible? [closed]
Impossible assumes we know everything there is to know about, well, everything. There was a time when everything mad knew said that traveling faster than the speed of sound was impossible. These same ...
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Source of the odor in space
If space is a vacuum, then how can it contain an odor? I read that after spacewalks, astronauts detected an unusual odor after removing their spacesuits. It was compared to the smell of a candle ...
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Why is Space 3D?
Why is Space a THREE DIMENSIONAL ENTITY?
I know that In physics and mathematics, the dimension of a mathematical space is informally defined as the minimum number of coordinates needed to specify any ...
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Is sky-glow affected by height?
I'm an architecture student and my graduation project will consist of building a research center for outer space, my question is whether or not height would affect sky-glow or not ? Thanks in advance, ...
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Type II supernovae as a distance indicator
Could someone explain in brief exactly how type II supernovae could be used as distance indicators? as in simply the formulae used and how they are employed? I know there are certain methods based on ...
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Why is the solar wind most powerful near the heliosphere?
I've read this article, titled, "Voyager Mission Finds a New Type of Electron Burst at The Edge of Our Solar System". They state that,
Carried to the fringes of our Solar System by the ...
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Where can I find galaxy spectra (in the form of FITS files)?
I know there's SDSS and I tried searching for the spectra through the navigate and explore tool under CAS as well as by using RA/Dec coordinates under SAS, but every single time it comes out with 0 ...
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what would the mass and density of Sirius A be if the mass of Sirius B is roughly the same as the Earth?
I am writing a blog post and while I am interested in astronomy I havent done any physics like this since high school. My question is: what would the mass and density of Sirius A be if the mass of ...
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Relation between mass of gas, mass of stars and dark matter halo mass [duplicate]
As we all know that Mass of the galaxy can be written as the sum of the mass of gas(Mg), the mass of stars (Ms), and mass of dark matter halo(Mh), as
M(galaxy)=Mg+Mh+Ms,
But is there any formula which ...
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List of galaxies with their dark matter halo
Where can one find the list of galaxies with their dark halo masses, I've searched several sites but I found no such proper list where the masses of their dark matter halo is compiled?
Can anybody ...
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How accurately could late 50s - early 60s humans have mapped the solar system?
What if early SETI investigations had focused on our own solar system, rather than distant stars?
Given the technology that existed around the 1950s, how much surveillance would humanity be able to do?...
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Has the idea of sending human heads instead of entire human bodies been considered in space exploration? [closed]
What makes human space exploration very difficult is the infrastructure required to support the human body outside earth. It must be researched, developed, and tested thoroughly which can take many ...
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Picking two random points in space and drawing a line between them, what is the chance the line intersects anything?
I thought of this question after pondering how most of the observable universe is observable. If we can observe it, then the space between us and that object must have been unoccupied to allow the ...
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Why is the position of the Sun so fixed? [duplicate]
Please correct me if I tell something wrong.
As we already know, a planet (e.g. Earth) remains on its orbit due to the gravity of the Sun.
If the Sun's gravity were not there, the Earth would be ...
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Is it possible to use the vacuum of space to help with pollution [closed]
Would it be possible to use a pipeline from the ground and uses the vacuum of space to dispose of things that are hazardous to the environment? (Liquid waste in particular comes to mind) Essentially ...
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What would happen if you jumped out of a moving spacecraft? [closed]
I've watched a film where one of the characters claimed to have rapidly disembarked a moving spacecraft during a 5g burn (?!) and immediately wondered how he survived.
For example, you're on a ...
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Definition of space - to cope with "space expansion"
I've searched quite a lot but found no satisfying definition, so please:
How do we actually define space when talking of "space expansion"? Isn't it just a metric, a dimension we measure, instead of ...
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