Obtaining the Light curve of a a Quasar

So, I am relatively comfortable with handling $$\textit{FITS}$$ files and hence I choose Python for the following operation. The thing is that I need to analyse some Quasar light curves and hence I went to the DR14Q data release of the SDSS Survey here in order to obtain the information on the Quasar Files (Big file don't open on data).

When I opened this files header on Python, I obtain:

hdu_list = fits.open(file_pth)
hdu_list.info()


where file_pth is the fits file location.

I obtain the following output:

Filename: /content/drive/MyDrive/RAD PRAC/SDSS.fits
No.    Name      Ver    Type      Cards   Dimensions   Format
0  PRIMARY       1 PrimaryHDU      16   (7055,)   uint8
1  DR14Q_v4_4    1 BinTableHDU    328   526356R x 105C   [18A, D, D, J, I, J, I, 4A, D, D, 4A, D, D, D, I, D, D, D, K, K, K, K, K, K, I, I, I, 51J, 51J, 51J, 51A, D, D, I, A, I, I, A, 5D, 5D, 5D, 5D, D, 5D, D, D, D, D, D, D, D, D, D, D, D, E, D, D, D, D, D, D, E, I, D, D, E, I, D, D, E, I, D, D, D, D, D, D, D, D, D, D, D, D, D, D, D, D, D, 4A, 4A, D, E, D, D, D, D, D, D, D, D, I, D, D, D]


Now, I try to open the file to see the whole array of data and I am confused out of these data given:

XTENSION= 'BINTABLE'           / binary table extension
BITPIX  =                    8 / 8-bit bytes
NAXIS   =                    2 / 2-dimensional table
NAXIS1  =                 1505 / width of table in bytes
NAXIS2  =               526356 / number of rows in table
PCOUNT  =                    0 / size of special data area
GCOUNT  =                    1 / one data group
TFIELDS =                  105 / number of columns
EXTNAME = 'DR14Q_v4_4'         / table name
TTYPE1  = 'SDSS_NAME'          / label for column 1
TFORM1  = '18A     '           / format for column 1
TUNIT1  = '-       '           / units for column 1
TTYPE2  = 'RA      '           / label for column 2
TFORM2  = 'D       '           / format for column 2
TUNIT2  = 'deg     '           / units for column 2
TTYPE3  = 'DEC     '           / label for column 3
TFORM3  = 'D       '           / format for column 3
TUNIT3  = 'deg     '           / units for column 3
TTYPE4  = 'THING_ID'           / label for column 4
TFORM4  = 'J       '           / format for column 4
TUNIT4  = '-       '           / units for column 4
TTYPE5  = 'PLATE   '           / label for column 5
TFORM5  = 'I       '           / format for column 5
TUNIT5  = '-       '           / units for column 5
TTYPE6  = 'MJD     '           / label for column 6
TFORM6  = 'J       '           / format for column 6
TUNIT6  = '-       '           / units for column 6
TTYPE7  = 'FIBERID '           / label for column 7
TFORM7  = 'I       '           / format for column 7
TUNIT7  = '-       '           / units for column 7
TTYPE8  = 'SPECTRO '           / label for column 8
TFORM8  = '4A      '           / format for column 8
TUNIT8  = '-       '           / units for column 8
TTYPE9  = 'Z       '           / label for column 9
TFORM9  = 'D       '           / format for column 9
TUNIT9  = '-       '           / units for column 9
TTYPE10 = 'Z_ERR   '           / label for column 10
TFORM10 = 'D       '           / format for column 10
TUNIT10 = '-       '           / units for column 10
TTYPE11 = 'SOURCE_Z'           / label for column 11
TFORM11 = '4A      '           / format for column 11
TUNIT11 = '-       '           / units for column 11
TTYPE12 = 'Z_VI    '           / label for column 12
TFORM12 = 'D       '           / format for column 12
TUNIT12 = '-       '           / units for column 12
TTYPE13 = 'Z_PIPE  '           / label for column 13
TFORM13 = 'D       '           / format for column 13
TUNIT13 = '-       '           / units for column 13
TTYPE14 = 'Z_PIPE_ERR'         / label for column 14
TFORM14 = 'D       '           / format for column 14
TUNIT14 = '-       '           / units for column 14
TTYPE15 = 'ZWARNING'           / label for column 15
TFORM15 = 'I       '           / format for column 15
TUNIT15 = '-       '           / units for column 15
TTYPE16 = 'Z_PCA   '           / label for column 16
TFORM16 = 'D       '           / format for column 16
TUNIT16 = '-       '           / units for column 16
TTYPE17 = 'Z_PCA_ER'           / label for column 17
TFORM17 = 'D       '           / format for column 17
TUNIT17 = '-       '           / units for column 17
TTYPE18 = 'Z_MGII  '           / label for column 18
TFORM18 = 'D       '           / format for column 18
TUNIT18 = '-       '           / units for column 18
TTYPE19 = 'BOSS_TARGET1'       / label for column 19
TFORM19 = 'K       '           / format for column 19
TUNIT19 = '-       '           / units for column 19
TTYPE20 = 'ANCILLARY_TARGET1'  / label for column 20
TFORM20 = 'K       '           / format for column 20
TUNIT20 = '-       '           / units for column 20
TTYPE21 = 'ANCILLARY_TARGET2'  / label for column 21
TFORM21 = 'K       '           / format for column 21
TUNIT21 = '-       '           / units for column 21
TTYPE22 = 'EBOSS_TARGET0'      / label for column 22
TFORM22 = 'K       '           / format for column 22
TUNIT22 = '-       '           / units for column 22
TTYPE23 = 'EBOSS_TARGET1'      / label for column 23
TFORM23 = 'K       '           / format for column 23
TUNIT23 = '-       '           / units for column 23
TTYPE24 = 'EBOSS_TARGET2'      / label for column 24
TFORM24 = 'K       '           / format for column 24
TUNIT24 = '-       '           / units for column 24
TTYPE25 = 'N_SPEC_SDSS'        / label for column 25
TFORM25 = 'I       '           / format for column 25
TUNIT25 = '-       '           / units for column 25
TTYPE26 = 'N_SPEC_BOSS'        / label for column 26
TFORM26 = 'I       '           / format for column 26
TUNIT26 = '-       '           / units for column 26
TTYPE27 = 'N_SPEC  '           / label for column 27
TFORM27 = 'I       '           / format for column 27
TUNIT27 = '-       '           / units for column 27
TTYPE28 = 'PLATE_DUPLICATE'    / label for column 28
TFORM28 = '51J     '           / format for column 28
TUNIT28 = '-       '           / units for column 28
TTYPE29 = 'MJD_DUPLICATE'      / label for column 29
TFORM29 = '51J     '           / format for column 29
TUNIT29 = '-       '           / units for column 29
TTYPE30 = 'FIBERID_DUPLICATE'  / label for column 30
TFORM30 = '51J     '           / format for column 30
TUNIT30 = '-       '           / units for column 30
TTYPE31 = 'SPECTRO_DUPLICATE'  / label for column 31
TFORM31 = '51A     '           / format for column 31
TUNIT31 = '-       '           / units for column 31
TDIM31  = '(1,51)  '           / dimensions for column 31
TTYPE32 = 'BI_CIV  '           / label for column 32
TFORM32 = 'D       '           / format for column 32
TUNIT32 = 'km/s    '           / units for column 32
TTYPE33 = 'ERR_BI_CIV'         / label for column 33
TFORM33 = 'D       '           / format for column 33
TUNIT33 = 'km/s    '           / units for column 33
TTYPE34 = 'RUN_NUMBER'         / label for column 34
TFORM34 = 'I       '           / format for column 34
TUNIT34 = '-       '           / units for column 34
TTYPE35 = 'RERUN_NUMBER'       / label for column 35
TFORM35 = 'A       '           / format for column 35
TUNIT35 = '-       '           / units for column 35
TTYPE36 = 'COL_NUMBER'         / label for column 36
TFORM36 = 'I       '           / format for column 36
TUNIT36 = '-       '           / units for column 36
TTYPE37 = 'FIELD_NUMBER'       / label for column 37
TFORM37 = 'I       '           / format for column 37
TUNIT37 = '-       '           / units for column 37
TTYPE38 = 'OBJ_ID  '           / label for column 38
TFORM38 = 'A       '           / format for column 38
TUNIT38 = '-       '           / units for column 38
TTYPE39 = 'PSFFLUX '           / label for column 39
TFORM39 = '5D      '           / format for column 39
TUNIT39 = 'nanomaggies'        / units for column 39
TTYPE40 = 'IVAR_PSFFLUX'       / label for column 40
TFORM40 = '5D      '           / format for column 40
TUNIT40 = '-       '           / units for column 40
TTYPE41 = 'PSFMAG  '           / label for column 41
TFORM41 = '5D      '           / format for column 41
TUNIT41 = 'mag     '           / units for column 41
TTYPE42 = 'ERR_PSFMAG'         / label for column 42
TFORM42 = '5D      '           / format for column 42
TUNIT42 = 'mag     '           / units for column 42
TTYPE43 = 'MI      '           / label for column 43
TFORM43 = 'D       '           / format for column 43
TUNIT43 = '-       '           / units for column 43
TTYPE44 = 'GAL_EXT '           / label for column 44
TFORM44 = '5D      '           / format for column 44
TUNIT44 = 'mag     '           / units for column 44
TTYPE45 = 'RASS_COUNTS'        / label for column 45
TFORM45 = 'D       '           / format for column 45
TUNIT45 = 'counts/s'           / units for column 45
TTYPE46 = 'RASS_COUNTS_SNR'    / label for column 46
TFORM46 = 'D       '           / format for column 46
TUNIT46 = '-       '           / units for column 46
TTYPE47 = 'SDSS2ROSAT_SEP'     / label for column 47
TFORM47 = 'D       '           / format for column 47
TUNIT47 = 'arcsec  '           / units for column 47
TTYPE48 = 'FLUX_0.2_2.0keV'    / label for column 48
TFORM48 = 'D       '           / format for column 48
TUNIT48 = 'erg/s/cm2'          / units for column 48
TTYPE49 = 'FLUX_0.2_2.0keV_ERR' / label for column 49
TFORM49 = 'D       '           / format for column 49
TUNIT49 = 'erg/s/cm2'          / units for column 49
TTYPE50 = 'FLUX_2.0_12.0keV'   / label for column 50
TFORM50 = 'D       '           / format for column 50
TUNIT50 = 'erg/s/cm2'          / units for column 50
TTYPE51 = 'FLUX_2.0_12.0keV_ERR' / label for column 51
TFORM51 = 'D       '           / format for column 51
TUNIT51 = 'erg/s/cm2'          / units for column 51
TTYPE52 = 'FLUX_0.2_12.0keV'   / label for column 52
TFORM52 = 'D       '           / format for column 52
TUNIT52 = 'erg/s/cm2'          / units for column 52
TTYPE53 = 'FLUX_0.2_12.0keV_ERR' / label for column 53
TFORM53 = 'D       '           / format for column 53
TUNIT53 = 'erg/s/cm2'          / units for column 53
TTYPE54 = 'LUM_0.2_12.0keV'    / label for column 54
TFORM54 = 'D       '           / format for column 54
TUNIT54 = 'erg/s   '           / units for column 54
TTYPE55 = 'SDSS2XMM_SEP'       / label for column 55
TFORM55 = 'D       '           / format for column 55
TUNIT55 = 'arcsec  '           / units for column 55
TTYPE56 = 'GALEX_MATCHED'      / label for column 56
TFORM56 = 'E       '           / format for column 56
TUNIT56 = '-       '           / units for column 56
TTYPE57 = 'FUV     '           / label for column 57
TFORM57 = 'D       '           / format for column 57
TUNIT57 = '-       '           / units for column 57
TTYPE58 = 'FUV_IVAR'           / label for column 58
TFORM58 = 'D       '           / format for column 58
TUNIT58 = '-       '           / units for column 58
TTYPE59 = 'NUV     '           / label for column 59
TFORM59 = 'D       '           / format for column 59
TUNIT59 = '-       '           / units for column 59
TTYPE60 = 'NUV_IVAR'           / label for column 60
TFORM60 = 'D       '           / format for column 60
TUNIT60 = '-       '           / units for column 60
TTYPE61 = 'JMAG    '           / label for column 61
TFORM61 = 'D       '           / format for column 61
TUNIT61 = 'Vega    '           / units for column 61
TTYPE62 = 'ERR_JMAG'           / label for column 62
TFORM62 = 'D       '           / format for column 62
TUNIT62 = 'Vega    '           / units for column 62
TTYPE63 = 'JSNR    '           / label for column 63
TFORM63 = 'E       '           / format for column 63
TUNIT63 = '-       '           / units for column 63
TTYPE64 = 'JRDFLAG '           / label for column 64
TFORM64 = 'I       '           / format for column 64
TUNIT64 = '-       '           / units for column 64
TTYPE65 = 'HMAG    '           / label for column 65
TFORM65 = 'D       '           / format for column 65
TUNIT65 = 'Vega    '           / units for column 65
TTYPE66 = 'ERR_HMAG'           / label for column 66
TFORM66 = 'D       '           / format for column 66
TUNIT66 = 'Vega    '           / units for column 66
TTYPE67 = 'HSNR    '           / label for column 67
TFORM67 = 'E       '           / format for column 67
TUNIT67 = '-       '           / units for column 67
TTYPE68 = 'HRDFLAG '           / label for column 68
TFORM68 = 'I       '           / format for column 68
TUNIT68 = '-       '           / units for column 68
TTYPE69 = 'KMAG    '           / label for column 69
TFORM69 = 'D       '           / format for column 69
TUNIT69 = 'Vega    '           / units for column 69
TTYPE70 = 'ERR_KMAG'           / label for column 70
TFORM70 = 'D       '           / format for column 70
TUNIT70 = 'Vega    '           / units for column 70
TTYPE71 = 'KSNR    '           / label for column 71
TFORM71 = 'E       '           / format for column 71
TUNIT71 = '-       '           / units for column 71
TTYPE72 = 'KRDFLAG '           / label for column 72
TFORM72 = 'I       '           / format for column 72
TUNIT72 = '-       '           / units for column 72
TTYPE73 = 'SDSS2MASS_SEP'      / label for column 73
TFORM73 = 'D       '           / format for column 73
TUNIT73 = 'arcsec  '           / units for column 73
TTYPE74 = 'W1MAG   '           / label for column 74
TFORM74 = 'D       '           / format for column 74
TUNIT74 = '-       '           / units for column 74
TTYPE75 = 'ERR_W1MAG'          / label for column 75
TFORM75 = 'D       '           / format for column 75
TUNIT75 = '-       '           / units for column 75
TTYPE76 = 'W1SNR   '           / label for column 76
TFORM76 = 'D       '           / format for column 76
TUNIT76 = '-       '           / units for column 76
TTYPE77 = 'W1CHI2  '           / label for column 77
TFORM77 = 'D       '           / format for column 77
TUNIT77 = '-       '           / units for column 77
TTYPE78 = 'W2MAG   '           / label for column 78
TFORM78 = 'D       '           / format for column 78
TUNIT78 = '-       '           / units for column 78
TTYPE79 = 'ERR_W2MAG'          / label for column 79
TFORM79 = 'D       '           / format for column 79
TUNIT79 = '-       '           / units for column 79
TTYPE80 = 'W2SNR   '           / label for column 80
TFORM80 = 'D       '           / format for column 80
TUNIT80 = '-       '           / units for column 80
TTYPE81 = 'W2CHI2  '           / label for column 81
TFORM81 = 'D       '           / format for column 81
TUNIT81 = '-       '           / units for column 81
TTYPE82 = 'W3MAG   '           / label for column 82
TFORM82 = 'D       '           / format for column 82
TUNIT82 = '-       '           / units for column 82
TTYPE83 = 'ERR_W3MAG'          / label for column 83
TFORM83 = 'D       '           / format for column 83
TUNIT83 = '-       '           / units for column 83
TTYPE84 = 'W3SNR   '           / label for column 84
TFORM84 = 'D       '           / format for column 84
TUNIT84 = '-       '           / units for column 84
TTYPE85 = 'W3CHI2  '           / label for column 85
TFORM85 = 'D       '           / format for column 85
TUNIT85 = '-       '           / units for column 85
TTYPE86 = 'W4MAG   '           / label for column 86
TFORM86 = 'D       '           / format for column 86
TUNIT86 = '-       '           / units for column 86
TTYPE87 = 'ERR_W4MAG'          / label for column 87
TFORM87 = 'D       '           / format for column 87
TUNIT87 = '-       '           / units for column 87
TTYPE88 = 'W4SNR   '           / label for column 88
TFORM88 = 'D       '           / format for column 88
TUNIT88 = '-       '           / units for column 88
TTYPE89 = 'W4CHI2  '           / label for column 89
TFORM89 = 'D       '           / format for column 89
TUNIT89 = '-       '           / units for column 89
TTYPE90 = 'CC_FLAGS'           / label for column 90
TFORM90 = '4A      '           / format for column 90
TUNIT90 = '-       '           / units for column 90
TTYPE91 = 'PH_FLAGS'           / label for column 91
TFORM91 = '4A      '           / format for column 91
TUNIT91 = '-       '           / units for column 91
TTYPE92 = 'SDSS2WISE_SEP'      / label for column 92
TFORM92 = 'D       '           / format for column 92
TUNIT92 = 'arcsec  '           / units for column 92
TTYPE93 = 'UKIDSS_MATCHED'     / label for column 93
TFORM93 = 'E       '           / format for column 93
TUNIT93 = '-       '           / units for column 93
TTYPE94 = 'YFLUX   '           / label for column 94
TFORM94 = 'D       '           / format for column 94
TUNIT94 = 'W/m2/Hz '           / units for column 94
TTYPE95 = 'YFLUX_ERR'          / label for column 95
TFORM95 = 'D       '           / format for column 95
TUNIT95 = 'W/m2/Hz '           / units for column 95
TTYPE96 = 'JFLUX   '           / label for column 96
TFORM96 = 'D       '           / format for column 96
TUNIT96 = 'W/m2/Hz '           / units for column 96
TTYPE97 = 'JFLUX_ERR'          / label for column 97
TFORM97 = 'D       '           / format for column 97
TUNIT97 = 'W/m2/Hz '           / units for column 97
TTYPE98 = 'HFLUX   '           / label for column 98
TFORM98 = 'D       '           / format for column 98
TUNIT98 = 'W/m2/Hz '           / units for column 98
TTYPE99 = 'HFLUX_ERR'          / label for column 99
TFORM99 = 'D       '           / format for column 99
TUNIT99 = 'W/m2/Hz '           / units for column 99
TTYPE100= 'KFLUX   '           / label for column 100
TFORM100= 'D       '           / format for column 100
TUNIT100= 'W/m2/Hz '           / units for column 100
TTYPE101= 'KFLUX_ERR'          / label for column 101
TFORM101= 'D       '           / format for column 101
TUNIT101= 'W/m2/Hz '           / units for column 101
TTYPE102= 'FIRST_MATCHED'      / label for column 102
TFORM102= 'I       '           / format for column 102
TUNIT102= '-       '           / units for column 102
TTYPE103= 'FIRST_FLUX'         / label for column 103
TFORM103= 'D       '           / format for column 103
TUNIT103= 'mJy     '           / units for column 103
TTYPE104= 'FIRST_SNR'          / label for column 104
TFORM104= 'D       '           / format for column 104
TUNIT104= '-       '           / units for column 104
TTYPE105= 'SDSS2FIRST_SEP'     / label for column 105
TFORM105= 'D       '           / format for column 105
TUNIT105= 'arcsec  '           / units for column 105
DATE-HDU= '2017-12-08T23:27:28' / Date of HDU creation (UTC)
STILVERS= '3.2-1   '           / Version of STIL software
STILCLAS= 'uk.ac.starlink.votable.FitsPlusTableWriter' / Author class in STIL so


What should I choose to plot the light curve of one Quasar? Or are there other repositories for plotting light curves? Thanks for helping!

• But SDSS doesn't produce quasar light curves? As the web page you have linked says - "The content of the SDSS-DR14 Quasar Catalog is described in Table 5 of Pâris et al. (2018). The detailed description of the data model is available here." Oct 9, 2021 at 15:22
• Oh I see that now. Apologies. Oct 9, 2021 at 16:24
• Would you be able to tell me how can I obtain light curve of a Quasar for analysis purpose? I wish to learn from the light curve a theory i have worked out! Oct 9, 2021 at 16:25
• I suggest you reformulate a question along those lines. Oct 9, 2021 at 17:04
• I tried to ask the specific new question here. Oct 9, 2021 at 19:59