Questions tagged [astropy]
Questions related to Astropy, a community Python package for Astronomy
68
questions
2
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1
answer
277
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L2 point ephemeris (celestial mechanics)
I'm a master student and I am trying to get the L2 ephemeris for some calculations in my master's project. It was kinda hard to find a file with the L2 ephemeris, but once I found it, I tried the next ...
2
votes
1
answer
226
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How to query a region on the sky when given only ecliptic coordinates?
I am new at using the Python packages astropy/astroquery and what I want to achieve is to use it to find stars that lay on the TESS continuous view zone (CVZ).
I ...
3
votes
1
answer
336
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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, ...
8
votes
3
answers
12k
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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
1
answer
977
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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 ...
2
votes
0
answers
356
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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
1
answer
1k
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Making sense of the lomb-scargle periodogram
I am trying to use the periodogram to tell when a signal is periodic or not by following the tutorial for the astropy Lomb-scargle periodogram here.
http://docs.astropy.org/en/stable/stats/...
1
vote
0
answers
182
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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
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2
answers
2k
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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 ...
3
votes
3
answers
911
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Differences between alt/az in Stellarium and Astropy
I've just started to learn Astropy. It's a nifty tool. Using some tutorials, I wrote and then made modifications to a little script that finds the Alt/Az of an object at a certain place and time. I ...
3
votes
0
answers
35
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Telluric Interference data
I am looking to create a function to correct for telluric interference and to do so I need to find data on Ozone interference.
It has been suggested to me that Astropy may have a function that does a ...
0
votes
1
answer
282
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Get visible galactic longitudes in astropy
I would like to know which part of the Milky Way is currently up. Preferably using astropy. The ingredients I have are the current time, and my current position on earth. How would I use these to get ...
1
vote
2
answers
676
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Retrieving input effective radius from Sérsic profile
I'm playing around with Sérsic profiles, and would like to retrieve the effective (half-light) radius that I put in by integration of the profile. I'm not managing to, so perhaps someone can help me ...
3
votes
2
answers
241
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Are 3D coordinate data from Sloan DSS-III available & easily accessible to non-pros?
Of course the newly announced SDSS-III data and maps from the Sloan Digital Sky Survey with 1.2 million objects, along with all previous data sets are openly available, and I'm sure there are many ...
1
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0
answers
626
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Plot an AltAz grid over a square grid of RADec points
first post here. As I'm new, StackExchange won't let create or use the wcsaxes tag. wcsaxes looks like the most appropriate tool for the job, but astropy is closely related.
I think the title says ...
1
vote
1
answer
446
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How to get error out of astropy constants
How do I get the error value out of an astropy.constants quantity?
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1
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1
answer
790
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What does the BinTableHDU store?
I'm just getting started with very primitive analysis of FITS data, and I have a 'raw' FITS file which I don't know how to get different wavebands of data from (if this is even possible).
...
2
votes
1
answer
183
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Difference in redshift between 2 interacting galaxies
I have a galaxy 'A', say at redshift 1. Let's suppose this galaxy has no peculiar velocity. What would be the redshift of another galaxy 'B', that has a radial velocity of 500 km/s, relative to A?
...