Questions tagged [sloan-dss]
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15 questions
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Trying to use SQL to query SDSS
I'm trying to use the SQL search at https://skyserver.sdss.org/dr18/SearchTools/sql to find (for example) QSOs with accurate redshifts from the SDSS. My query will look something like this:
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Is the code that produces the SDSS DR16Q quasar catalogue available?
I'm curious if it's available to investigate (from my question in the title), or even better, modify and re-run. See SDSS DR16Q quasar catalogue.
Not the data itself, that's in a fits file. The code ...
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Not finding some FITS Spectra files in SDSS
I'm trying to automate downloading FITS files from SDSS. Currently, I'm getting information on the plate, mjd, and fiberID of certain objects from an SQL query on SpecObj, which I'm using in an url ...
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Sloan Digital Sky Survey - Obtaining Spectral and Photometric Datasets
I am working on a soft computing (fuzzy logic), genetic algorithm, explainable AI (XAI) classification system for astronomical objects from the Sloan Digital Sky Survey. The dataset I am currently ...
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What are mag_a, mag_i, mag_z, a*, and sin_i * from the SDSS Moving Objects Data?
I'm currently working on the SDSS Moving Objects data sets and came across the column names mag_a, mag_i, mag_z, aprime, and sin_iprime. Can someone describe what these attributes mean, or where I can ...
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spider image in Samuel Oschin Schmidt Telescope DSS imagery
I was puzzled by image artifacts that appear in DSS-2 (blue) survey.
These images were taken by the Samuel Oschin Schmidt Telescope on photographic plates and later digitized. They are also available ...
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Accessing SDSS server SQL server via python
Is there a way to directly access any of the Sloan Digital Sky Survey servers via SQL via Python?
Currently I have been able to run SQL queries from the website they provide (for example https://...
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How to place an observer in a cosmological simulation
Suppose I have a cosmological simulation with points in xyz space at a certain redshift in a cube like this:
And I have these for many cubes of different redshifts say from z=0 to z=2. Now I want to ...
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Getting XYZ coordinates of Luminous Red Galaxies catalogue
So I want to get the XYZ (rectangular/Cartesian) coordinates of the LRG (luminous red galaxies) catalog. The catalog is available for download from here: https://data.sdss.org/sas/dr16/eboss/lss/...
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SDSS - getting separate u, g, r, i, z frames from SWARP tool and astropy
I am following this paper to extract the u,g,r,i,z image frames from the SDSS image fits files. I have the fits files downloaded (using the bulk data download option from SDSS) and tried to run the ...
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Q: Calculating the luminosity of a galaxy
I am currently working on a project on which I am calculating the luminosity of galaxies by using the SDSS data. They use a system of asinh magnitudes, and according to their website they use a system ...
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Error associated with Sersic Profile calculations?
I am working on a Bayesian analysis project for class using data I gathered some data from NASA's Sloan Atlas (http://www.nsatlas.org/). One of the variables I am dealing with is the Sérsic Index (...
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What (actually) does "peculiar periodic spectral modulations" refer to in this preprint?
I saw this ArXiv preprint after reading about it in the popular media.
I can not even understand the beginning of the introduction (much less the whole paper):
INTRODUCTION
A Fourier transform ...
- 30.7k
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Sloan Digital Sky Survey (SDSS) HDU `or_mask` - what does it mean exactly?
I'm looking at the Sloan Digital Sky Survey data. I'm primarily using the flux data, from the documentation I see the first extend (HDU 1) has flux, ...
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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 ...
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