SDSS Galaxy Subset

<p>The&nbsp;<a href="https://www.sdss.org">Sloan Digital Sky Survey</a>&nbsp; (SDSS) is a comprehensive survey of the northern sky. This dataset contains a subset of this survey, of 100077&nbsp;objects classified as galaxies, it includes a CSV file with a collection of information and a set of files for each object, namely JPG image files, FITS and spectra data. This dataset is used to train and explore the&nbsp;<a href="https://github.com/nunorc/astromlp-models">astromlp-models</a>&nbsp;collection of deep learning models for galaxies characterisation.</p> <p>The dataset includes a CSV data file where each row is an object from the SDSS database, and with the following columns (note that some data may not be available for all objects):</p> <ul> <li><strong>objid</strong>: unique SDSS object identifier&nbsp;</li> <li><strong>mjd</strong>: MJD of observation</li> <li><strong>plate</strong>: plate identifier</li> <li><strong>tile</strong>: tile identifier</li> <li><strong>fiberid</strong>: fiber identifier</li> <li><strong>run</strong>: run number</li> <li><strong>rerun</strong>: rerun number</li> <li><strong>camcol</strong>: camera column</li> <li><strong>field</strong>: field number</li> <li><strong>ra</strong>: right ascension</li> <li><strong>dec</strong>: declination</li> <li><strong>class</strong>: spectroscopic class (only objetcs with GALAXY are included)</li> <li><strong>subclass</strong>: spectroscopic subclass</li> <li><strong>modelMag_u</strong>: better of DeV/Exp magnitude fit for band u</li> <li><strong>modelMag_g</strong>: better of DeV/Exp magnitude fit for band g</li> <li><strong>modelMag_r</strong>: better of DeV/Exp magnitude fit for band r</li> <li><strong>modelMag_i</strong>: better of DeV/Exp magnitude fit for band i</li> <li><strong>modelMag_z</strong>: better of DeV/Exp magnitude fit for band z</li> <li><strong>redshift</strong>: final redshift from SDSS data z</li> <li><strong>stellarmass</strong>: stellar mass extracted from the&nbsp;<a href="https://www.sdss.org/dr16/spectro/eboss-firefly-value-added-catalog">eBOSS Firefly catalog</a></li> <li><strong>w1mag</strong>: WISE W1 &quot;standard&quot; aperture magnitude</li> <li><strong>w2mag</strong>: WISE W2 &quot;standard&quot; aperture magnitude</li> <li><strong>w3mag</strong>: WISE W3 &quot;standard&quot; aperture magnitude</li> <li><strong>w4mag</strong>: WISE W4 &quot;standard&quot; aperture magnitude</li> <li><strong>gz2c_f</strong>: Galaxy Zoo 2 classification from&nbsp;<a href="https://academic.oup.com/mnras/article/435/4/2835/1022913">Willett et al 2013</a></li> <li><strong>gz2c_s</strong>: simplified version of Galaxy Zoo 2 classification (<a href="https://github.com/nunorc/astromlp-models#galaxy-zoo-2-simplified-classes-gz2c">labels set</a>)</li> </ul> <p>Besides the CSV file a set of directories are included in the dataset, in each directory you&#39;ll find a list of files named after the <strong>objid&nbsp;</strong>column from the CSV file, with the corresponding data, the following directories tree is&nbsp;available:</p> <pre><code class="language-bash">sdss-gs/ ├── data.csv ├── fits ├── img ├── spectra └── ssel</code></pre> <p>Where, each directory contains:</p> <ul> <li><strong>img</strong>: RGB images from the object in JPEG format, 150x150 pixels, generated using the&nbsp;<a href="https://skyserver.sdss.org/dr16/en/help/docs/api.aspx">SkyServer DR16 API</a></li> <li><strong>fits</strong>: FITS data subsets around the object across the u, g, r, i, z bands; cut is done using the&nbsp;<a href="https://github.com/jhoar/ImageCutter">ImageCutter</a>&nbsp;library</li> <li><strong>spectra</strong>: full best fit spectra data from SDSS between 4000 and 9000 wavelengths</li> <li><strong>ssel</strong>: best fit spectra data from SDSS for specific selected intervals of wavelengths discussed by&nbsp;<a href="https://arxiv.org/abs/1003.3186">S&aacute;nchez Almeida 2010</a></li> </ul> <p><strong>Changelog</strong></p> <ul> <li>v0.0.4&nbsp;- Increase number of&nbsp;objects to ~100k.</li> <li>v0.0.3&nbsp;- Increase number of&nbsp;objects to ~80k.</li> <li>v0.0.2&nbsp;- Increase number of&nbsp;objects to ~60k.</li> <li>v0.0.1 - Initial import.</li> </ul>