Questions tagged [python]

Questions about using the Python programming language to solve astronomical problems. General questions about Python are off-topic but might be asked on Stack Overflow.

Filter by
Sorted by
Tagged with
2
votes
0answers
15 views

Detect sources near image edge with python photutils

As my question suggests, I 'm trying to use a python library photutils in order to detect sources from MUSE cube. MUSE (Multi Unit Spectroscopic Explorer) is an ...
1
vote
1answer
46 views

Python controllable amateur astrophotography cameras?

I would like to read further about any successes that amateur astrophotographers (or professionals) have had with USB CCD cameras that are controlled by Python scripts. I'd like to script the setting ...
1
vote
0answers
31 views

Python interface for DMK 23U274 USB camera for astrophotography

I have access to a monochrome USB camera (DMK 23U274, The Imaging Source) and I'd like to record focal plane images from a small telescope with a python script that would control it by setting ...
2
votes
1answer
55 views

Neutrino Modelling in Friedmann Equation

so I'm trying to model neutrinos in the Friedmann Equation. I've covered the case of the Benchmark Model where we have matter, radiation, curvature, and the cosmological constant, Lambda. I know my ...
-1
votes
1answer
56 views

Cannot plot Kepler FITS files with topcat in Windows

This is a continuation of my earlier question here. I was able to find Kepler data. Now I wanted to plot the data using Topcat. But when I tried to plot the data, I received error. Below is the error ...
4
votes
0answers
32 views

Converting pixel coordinates to world relative offset coordinates with astropy for plotting

Intro So, I'm having some trouble trying to figure out how I can convert pixel coordinates to world offset coordinates with the center lying on the source coordinates. I would include my fits file ...
2
votes
0answers
40 views

PHOEBE 2.2 Documentation, components and semi-major axis definitions

I'm looking at PHOEBE 2.2 Documentation, specifically at a tutorial about constraints What are Constraints? Constraints live in their own context of the Bundle, and many are created by default ...
1
vote
1answer
60 views

How to compute Ascension / Descension cycle of the Moon

I am struggling to find out an information about how to determine ascending/descending cycle of the Moon. I can find from this source and a bunch of others, that Moon begins to descend when reaches ...
1
vote
0answers
49 views

How are small objects automatically identified and their locations determined in digital images?

I have a large quantity of old digital images of low energy electron diffraction (LEED) patterns that I must process to identify and locate small, sometimes elongated gaussian-like blobs of a few ...
3
votes
1answer
142 views

Plotting Astronomical Data Using Python

I have been trying to create a graph which shows the distances between the stars and the earth, yet I could not obtain the desired graph as seen below (click to zoom in): My graph: As @uhoh ...
2
votes
2answers
72 views

Finding Quintuple Planetary Alignments with SkyField

I am working on a python script that will use the SkyField and SciPy libraries to find quintuple planetary conjunctions and their corresponding constellation location. Specifically I am looking for ...
1
vote
1answer
79 views

Could someone please explain to me how I can extract velocity component values from Stellarium, for a given planet?

For a project that I am currently working on, I would like to know how one could extract velocity component values ($v_x$, $v_y$ and $v_z$) for a planet from the Stellarium software. The current ...
3
votes
1answer
97 views

Propagate Earth trajectory for 1 Myr

What is the most accurate way of propagation of Earth trajectory relatively to the Sun? I need to calculate the Earth-Sun distance. Is there any library on Python? I've used before JPL Horizons, ...
1
vote
1answer
79 views

SPICE Alt Az example

Original question below, but my question is now about how can I supply lat/lon coordinates for other locations other than the one in the example below? It is possible to use NASA's SPICE toolkit to ...
1
vote
0answers
69 views

How to do logarithmic wavelength binning (in Python) in order to find redshift?

In Tonry and Davis (1979)(http://adsabs.harvard.edu/abs/1979AJ.....84.1511T), they formulated a cross-correlation method for extracting velocity redshifts. They bin the linear spectra into logarithmic ...
2
votes
0answers
60 views

Covariance matrix not calculated when fitting gaussians?

So I am using Astropy's basic models.Gaussian1D model and a fitter = fitting.LevMarLSQfitter() to fit 3 Gaussian pulses with some added random noise. The fit is good, but when I type fitter.fit_info, ...
6
votes
3answers
1k views

How do I plot galactic coordinates using matplotlib and astropy in python?

I want to make a projection of millisecond pulsars on the galactic plane, much like this one from Sala et al. 2004: I have tried several methods, and have not gotten anywhere. This is my current ...
1
vote
1answer
76 views

Plotting Galactic Longitude from 180 to -180

I made a scatter plot in Python that looks like this: However, I want galactic longitude, l, to be plotted from 180 to -180 like these graphs from Iorio and Belokurov (2019): Here is the ...
1
vote
1answer
267 views

Converting an RGB image to fits (astropy)

I am trying to save a NumPy RGB array (a 3d array with dimension 512x512x3), to a .fits file using astropy.io. Saving this array to a .png file works fine, but when ...
0
votes
1answer
47 views

Plot SuperWasp Lightcurves

I am trying to plot superwasp lightcurves in python from the fits files, using TMID and FLUX2, getting this: There is a way to transform the information so I can plot the lightcurves with the kepler ...
1
vote
0answers
91 views

Three Body Problem

I tried to solve the three body problem numerically. While after 1000 time steps the system looks stable (See Fig.1) it is completely unstable after 10000 time steps (See Fig.2). Is that an intrinsic ...
1
vote
0answers
123 views

To show perihelion precession motion of Mercury in Python with matplotlib

I'm trying to make it more general code so I can trace even a parabola or hyperbola for $e=1, E=0$ and $e>1, E>0$ respectively. And after achieving that general code I want to make the same code ...
2
votes
0answers
43 views

How would I code to find the seeing of a binary star system in python?

I have fit images of binary systems and want a program that will help determine which ones are highest quality, the seeing. The simplest way is apparently to equate it to the FWHM of the Gaussian of ...
1
vote
0answers
26 views

How can I get the fluxes of fetch_imaging_sample? - astroML

I'm working with astroML in Python and I need to get the fluxes from the magnitudes in r band of fetch_imaging_sample(). ...
0
votes
0answers
87 views

Smoothing an SED with binning

I have an (observed) SED of a galaxy, and am attempting to match model SEDs to it. To do this I need to be able to see its shape better, which would involve some sort of smoothing of the spectrum. I ...
1
vote
0answers
148 views

How to “slice” a fits table in astropy?

I have imported my fits table, hdul0, into python. I'm using astropy.table. I opened it with hdul0 = fits.open('filename'). hdul0data = Table(hdul0[1].data) I ...
2
votes
0answers
394 views

Astronomy/Astrophysics Project With C++/C/Python [closed]

I am a Computer Science Engineering student, in the 1st year of college. I'm insanely interested in making a project regarding astronomy/astrophysics but I don't know where to begin from. I know C, C++...
2
votes
2answers
138 views

How to convert celestial Coordinates with a radius, to max and min celestial coordinates?

I am writing a piece of python code to convert right ascension and declination with a given radius to minimum and maximum right ascension and declination. I firstly can't understand why the min and ...
1
vote
2answers
307 views

Earth Orbit Simulator [closed]

I'm trying to simulate Earth's orbit using 2nd Newton's Law and cartesian coordinates. The program seems ok, but when plotting graph, it's a parabola. I know the shape of orbit changes according ...
1
vote
0answers
76 views

Plotting GAIA barycentric radial velocity data with python

Does anybody know of a good tutorial on how to use python and astropy to generate plots of GAIA, RAVE or any other database of barycentric (heliocentric) radial velocity data of stars in our galaxy? ...
2
votes
1answer
204 views

Calculating right ascension for two planets and their separation using python

I am experimenting with the Python library PyEphem for astronomy, and I am trying to recreate/understand some of the basic calculations there. There is a function called separation that, given two ...
2
votes
2answers
877 views

Fitting PSF to an image to get total flux (Python)

I have an image of a single unsaturated source (asteroid) that I'd like to fit guesses for various model PSFs to, so that I can then compare the total flux in each case. I've only recently begun ...
1
vote
0answers
89 views

Comoving distance between two points [(RA1, Dec1, z1) and (RA2, Dec2, z2)]

I have Redshift (z), RA and Dec positions for two points in a galaxy catalogue (say P1 = [<...
2
votes
1answer
707 views

How to construct a sky map

First of all, I have very basic knowledge of astronomy so sorry if I make some mistakes in my terminology. I'd like to plot the Southern Cross. I can find the name of its 5 stars. Also, I have some ...
1
vote
0answers
57 views

Efficiently calculating power spectra from galaxy catalogs

I am dealing with a problem which requires calculating either the correlation function or the power spectrum. At times, the 2-point-correlator seems the better route, at others, the PS. Right now I am ...
2
votes
2answers
611 views

Python: Find brightest pixel in fits-file and ignore brighter artefacts

I have 4000 fits-files images from SPITZER, each containing the same star over a time period. Each image is a photmetry cube of 32 pixel * 32 pixel * 64 consequent time frames. I need to look through ...
5
votes
1answer
385 views

Generating random galaxy catalogs for correlation functions

The galaxy correlation function, when computed directly from a galaxy catalog, relies on computing a randomly generated counterpart catalog. When dealing with a simulated galaxy mock-catalog, where ...
1
vote
0answers
129 views

Error bar in Python [closed]

I have two column data as magnitude and period of several stars. I have plotted magnitude vs. period, but I need to add a column as error bar for Y values. How can I write the code to put the error ...
4
votes
1answer
548 views

Tests for code that computes two-point correlation function of galaxies

I'm currently writing a code to compute the two-point correlation function of a set of galaxies. As I work with a loooot of galaxies, it was suggested to me not to do it in real space, but to compute ...
2
votes
1answer
51 views

Obtain IR diffuse data from WISE

I need some help obtaining IR background diffuse data from the WISE observation. There is already some work done in this regard; see: http://wise.skymaps.info/ . These are .fits files. How do I find ...
4
votes
0answers
206 views

Generate probability skymap

I am trying to generate skymaps for a set of Fermi GBM triggers, containing the probability that a trigger originated in a given part of the sky. For each trigger, I have access to the RA, dec, error ...
1
vote
0answers
93 views

Unsure how to obtain galactic roll?

I am having some issues with understanding what my adviser means by "galactic roll," but I have not been able to find anything online regarding this. My project involves generating an array of az/el ...
2
votes
2answers
398 views

Converting FITS (NuSTAR) coordinates to WCS

I'm trying to convert some pixel coordinates I have into WCS coordinates, ideally into a WCS region for use in some further analysis. So far I've been able to load and parse a NuSTAR FITS file, do ...
3
votes
2answers
812 views

Eclipses with SkyField

I'm trying to compute solar eclipses for a long period of time, see Back-predicting solar eclipses Initially, I wanted at several points on Earth whether an eclipse was visible at some point in time. ...
1
vote
2answers
149 views

Problems with FITS headers

I'm working with some NEOWISE images that seem to have incomplete header tags. I've been advised by the SAO (because I'm using DS9 to view them) that I have "a partial PC matrix defined, yet it does ...
3
votes
1answer
436 views

What is the 2D elliptical projection of the Celestial Sphere called, and how can I make one?

I see this kind of projection of the celestial sphere into 2D frequently, usually with an image of the milky way galaxy or cosmic microwave background. This particular image shows the path of visible ...
6
votes
3answers
1k views

Generate an uniform distribution on the sky

How to generate an uniform distribution of stars on the sky ? What I want is make a simulation of random points following uniform distribution on a part of the sky (making the assuption that we have ...
1
vote
1answer
63 views

How are the days relating to right ascension around a polar star chart decided?

If you look at this link they have days realting to right acension. How did they calculate nov 20th == 0h, dec 6 == 1h? I was trying to calculate this in astropy, but I end up with nov 20th, 8pm == ...
3
votes
1answer
934 views

How do I create a galaxy stellar mass function?

Suppose that I have an array of stellar masses of tens of thousands of galaxies, and that I also already know what the total "survey volume" is (in Mpc^3) within which all of those galaxies are ...
3
votes
3answers
1k views

Python with image in fits format

I'm trying to write a Python program that will do the following: take an image in fits format and a reg file with a list of regions in the sky, and determine which regions in the list are inside the ...