Questions tagged [distances]
Questions regarding the amount of space between two objects, the units, or measurement thereof.
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What is the distance between Stephenson 2-18 and Earth?
The distance between Earth and Stephenson 2-18 is 19,570 light years (1.15×10¹⁷ miles). The thing that makes this reasonable is because the Earth is in the Milky Way Galaxy and Stephenson 2-18 is in ...
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Distance of the Crab nebula and the speed of light
I am watching a youtube video that says that, there is plenty of historic records that shows that the star, that turned into the Crab nebula, blew up in 1054. According to the video, it is located ...
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Orion stars distance from Earth
For a textbook I'm creating a figure depicting the distances of Orion constellation's stars from Earth.
However i wasn't able to found an Official Scientific catalog of most recent stars distance ...
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How did scientists decide the boundary of the Milky Way at Edwin Hubble times?
I know Edwin Hubble used Cepheid variables to prove the Andromeda Galaxy is not part of the Milky Way. But how did scientists at that time decide the boundary of the Milky Way?
And how did they find ...
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Finding an expression for the rate of change of Comoving volume with respect to redshift
I am trying to find the expression for the rate of change of comoving volume with respect to redshift, that is $\frac{\mathrm{d}V_c}{\mathrm{d}z}$. In this paper (Hogg, David W.), the comoving volume ...
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Large dataset of galaxies redshift, mass, and metallicity?
I'm curious if there is a standard dataset for redshift-mass or redshift-metallicity like there is for redshift-distance with Pantheon+SH0ES.
https://github.com/PantheonPlusSH0ES/DataRelease/tree/main/...
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Where to find data about as many stars as possible?
I need computer-readable data about as many stars as possible, with their:
distance to the Earth (or Sun),
their masses,
and if possible:
coordinates,
age,
brightness
distance to the center (...
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Planets revolving counter clockwise around the Sun
Planets revolving around the Sun
Hypothetical case:
What could have been or no impact if the planets viz Earth, Jupiter, Saturn, Mercury, Venus, Mars, Pluto, Uranus, Neptune in different orbits ...
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How to find the distance between stars
I wanted to calculate the distance between the end points of the Orion's belt (Alnitak and Mintaka).
I searched in the internet and I found out their angular separation to be 2.736°.
Then I searched ...
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Is Webb or any near-future telescopes like ELT capable of observing redshift changes to confirm General Relativity?
The (Davis and Lineweaver (2003)) "Expanding Confusion" paper states that "the expected change in redshift due to cosmological acceleration or deceleration is only ∆z ∼ 10^(−8) over 100 ...
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How can we estimate distance of galaxies by only redshift when there are other several factors other than distance to cause redshift
There are different factors for red appearance of different objects in the night sky. Two reasons which I know are
Star red by nature
Example: red supergiants
They emit red light because of their ...
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Why is a megaparsec considered to be a useful distance in astronomy?
Is the megaparsec fundamental or man made? I have read that galaxy clusters are megaparsecs wide for example.
user50623
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How can I get a list of the closest x stars and their distances from the Gaia ESA Archive using Python?
I've been trying to find this out for a while now, but I'm making zero progress. I really struggle to find good documentation for the query language, and even in the astroquery library I can't find ...
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Which value of the apparent magnitude do I use from a Supernova light curve
I am trying to get the distance modulus from a light curve of a supernova and obviously the apparent magnitude changes with time. Not only that but there are so many filters with different mags.
So my ...
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How to calculate distance between stars?
I have data on nearby stars, including galactic coordinates and distance from Sun. And I have a dilemma.
In a story I'm writing, I have two starfaring alien civilisations. One originates from a planet ...
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What equation tells you how far in space you can go from a point and return?
We know that hubble expansion increases the distance between points in space, and that the cosmological event horizon represents the distance from the observer at which objects are receding faster ...
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How to obtain luminosity distance from a light curve
I have some light curve data of a SN Ia from which I want to find the luminosity distance $D_L$.
How can I do it mathematically?
I'll then try to implement the answer using Python.
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How to calculate the distance from earth and Vega in 1000 years?
Hello I read that Vega is getting closer to earth.
I would like to learn how to calculate its displacement and calculate the galactic coordinates that it will have next year or in 1000 years.
Knowing ...
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Calculate the distance between two planets eliptical orbit point
What is the distance between Saturn's moons Polydeuces and Dione,
Looking for Kilometers if one was to travel Nearest and farthest based on orbit.
Best I can find:
"Polydeuces can get as close ...
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See Venus in daylight
At what distance (in angular degrees) from the Sun, could we see Venus, in mid daylight, with a pair of binoculars (7x50)?
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Determining the distance to the Moon from parallax using the following information
How could I determine the distance from the Earth to the moon by using the method of simultaneous parallax? I know the right ascension and declination as seen from two different points on earth. I ...
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How can a time-like trajectory be calculated using the Friedmann-Robertson-Walker metric?
Using the following FRW metric,
$$ds^2=-c^2dt^2+R^2(t)(d\chi^2+f(\chi)d\Omega)$$
and considering $d\Omega=0$ from now on, it is clear that for a light-like trajectory, the equation must read $ds^2=0$ ...
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What is the apparent size of Earth from the Sun?
Heatwaves have been in the news in recent years. I found it amazing to consider that the energy from the Sun is enough to kill you, when only a tiny fraction of its radiation reaches Earth.
Then I ...
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3d distance between the Galaxies inside the galaxy cluster
I am currently working on the dynamics of the galaxy cluster, so i am trying to get the distance between the galaxies inside the galaxy cluster from its centre. As a input i have RA , DEC and Z (...
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Farthest distance two objects are "gravitationally bounded", considering expansion of the Universe
The narrative is: "on greater scales the expansion of the Universe dominates, but on smaller scales gravitationally bounded objects still stay bounded". But how small is meant by "...
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Does stellar parallax only occur parallel to the ecliptic?
Does stellar parallax only occur parallel to the ecliptic, or has it been observed in other directions, too?
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What would Betelgeuse look like from Earth if it was at the edge of the Solar System
If we parked Betelgeuse just outside the Solar System, how big would it look from Earth?
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Distance from Earth to Mars at time of November 8, 2022 lunar eclipse maximum
I’m looking for the “exact” distance from the Earth to Mars, at the moment of the lunar eclipse maximum earlier this week (November 8, 2022). As many significant digits as you can muster.
Between the ...
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How dark is the side of the Moon facing away from the Sun? ( I don't mean the far side)
Remember, the actual "dark side" of the Moon is not the far side, facing away from us that we can't see, but rather it's the side that faces away from the Sun that is illuminating it.
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How can I convert a galaxy arcmin to light years?
https://en.wikipedia.org/wiki/List_of_largest_galaxies
says galaxy ESO 383-76 has a MA diameter of 1,764,000 light years based on information from
https://ned.ipac.caltech.edu/cgi-bin/objsearch?...
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What is the difference between the Synodic & the Sidereal Periods?
While studying Spherical Astronomy, I came to know the two terms: 'Synodic Period' & 'Sidereal Period'. Both were referring to the returning of a particular celestial body on the sky or the ...
user47535
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Redshift distance proportionality at high Z and need for "mighty mouse" galaxies?
Allegedly supported by some evidence from the new James Webb space telescope physicist Eric Lerner has written an article that have garnered some attention. He writes that:
"Put another way, the ...
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How much does foreground clumping affect the estimated sizes of high-redshift objects?
I've always converted angular to linear size by using the angular-diameter distance without really thinking about it. But in light of recent stories about high-$z$ galaxies observed by JWST being ...
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Distance of distant galaxies
Can two galaxies, one with a redshift of 7 and the other a redshift of 8 have the same angular distance (distance from the Earth during the emission of the observed photons)?
If not why ?
Example: ...
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Measurement unit of coordinate systems in astronomy
Nearly all of the coordinate system I have studied in Positional astronomy use the degree system. This makes me curious about why astronomers prefer degrees over radians as we know that Radian is a ...
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Space travel to distant stars
This is more of a hypothetical question.
Say space travel at near light speed was possible, and I wanted to travel in my spaceship to some distant star many light years away. At the time and location ...
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Is there something close to a consensus on Earth-Sun annual distance increase (speed)?
I've seen estimates varying by an order of magnitude, e.g. (New Scientist)
Having such a precise yardstick allowed Russian dynamicists Gregoriy A. Krasinsky and Victor A. Brumberg to calculate, in ...
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How do astronomers distinguish between Cepheids and other types of variable stars?
So my understanding of how Cepheid is used as standard candle to determine distance of galaxies is like this: Astronomers observe a galaxy, notice an object within that galaxy whose brightness ...
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In this image taken by Voyager 1, which is closer: the earth or the moon?
NASA reports this photo was taken 19 Sep 1977 by Voyager 1:
It doesn't strike me as obvious how to determine which celestial body is closer to Voyager 1 as the photo was taken. My (not very ...
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Distribution function for distance to nearest stars from any given star in our galaxy
If I pick any random star in our galaxy, what is the mean & std dev of distances from that star to its, say, 5 nearest neighbors? As this distribution likely depends on the distance from the ...
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Is V616 Monocerotis the closest black hole?
Now that HR 6819 has been found not to be a black hole after all, does that currently leave V616 Monocerotis as the closest known stellar mass black hole?
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How do we measure the current positions of galaxies?
I do wonder how do we measure current position of galaxies since all the information transfer speed of the universe is limited by the light speed.
My understanding is the we can only measure the ...
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How to build an adjacency matrix of stars connectivity from their physical kpc distances?
I'm probing into the Illustris API, and gathering information from a specific cosmos simulation, for a given redshift value.
This is how I request the api:
...
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Star charts showing distances instead of apparent magnitudes?
I am curious as to what star charts would look like, if instead of scaling the size of dots by apparent magnitude, the size of dots were scaled by actual distance from earth.
It would be nice to ...
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Compute Distance Between Stars
If I have the following information about star A and Star B, how can I compute the distance between A and B?
Distance from Sol for Star A
Right Ascension/Declination of Star A
Parallax/Absolute ...
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Am I miscalculating distance to Moon?
The Moon's orbital period is generally given as 27.3 days, and the radius of Geostationary orbit as 26,200 miles. However, using Kepler's Third Law, if I raise 27.3 to the power of 2/3, and multiply ...
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Is luminosity distance related to both heliocentric redshift and CMB restframe redshift？
The luminosity distance
$$d_l=(1+z)r(z)\ ,$$
where $r(z)$ is given by $$r(z)=cH^{-1}_0\int_{0}^{z}\frac{dz'}{E(z')}\ .$$
When I use the SNe dataset "Pantheon", I find there are two redshifts:...
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Can the Event Horizon Telescope been used to find intergalactic distances?
Now that we have the Event Horizon Telescope (EHT), why can't we just guess and check intergalactic distances by changing the EHT's focal length? For instance why don't we take another picture of M87,...
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How to calculate distance to other galaxies using type 1a supernova?
This is for a project in astronomy with extensive data analysis. How should I calculate the distance of galaxies using AGN and supernova Ia? I am using the data from dr17 of SDSS.
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What exactly is the estimated distance to a far-off object when they say '50 Mpc/h' or '50 Mpc h^-1'? Is it less than 50 Mpc? Do you ÷ by 67 or 74?
Several recent arxiv.org papers I read mention distances to very distant objects in Mpc (megaparsecs) divided by Hubble's 'constant'....
Does that mean we should divide the Mpc or Gpc (gigaparsecs) by ...
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