CL Aur (Eclipsing binary)

RA: 05h 12m 54.17s, DE: +33° 30' 27.90" (78.2257100000, 33.5077500000)

AsasSnV: ASASSN-V J051254.19+333028.0, Ato: ATO J078.2257+33.5077, Gaia: Gaia DR3 181924442315418112, Gcvs: CL Aur, Gsc: GSC 02393-01455, Nsvs: NSVS 6861100, Tic: TIC 367365974, TwoMass: 2MASS J05125418+3330280, Tyc: TYC 2393-1455-1, Other: HV 6886

10/17/2026, 06:24 - 10/17/2026, 09:48 (UTC)

Data:
  • Observer: Steven S. Smith
  • Created: 10/20/2026, 16:00 UTC
  • Updated by: Filip Walter
  • Updated: 10/21/2026, 13:36 UTC
  • Station: Vidor, Texas, USA
    Lat: +30°, Long: -94°
  • Instrument: William Optics RedCat 51 (51 mm aperture, 250 mm focal length); ZWO ASI1600MM Pro, gain 139, offset 10, 1x1 binning, -10 C. Optolong 1.25-inch H-alpha 7 nm, [O III] 6.5 nm and [S II] 6.5 nm filters; ZWO EFW.
  • Photometric band: H-alpha
  • Time standard: GJD
  • Brightness in: Mag
  • Magnitude type: Relative (V−C)
Note:
CL Aur, 2026-10-17 UTC; 14 retained exposures through H-alpha. Optolong 1.25-inch narrowband filter; nominal FWHM 7 nm (HASIIOIII-125 set). JD values are UTC exposure midpoints, uncorrected (not HJD/BJD). Relative ensemble magnitudes: this target's Oct 18 median is set to zero separately in each filter. This reference level is not a verified out-of-eclipse maximum; these are not standard magnitudes. Filters must remain separate.
Native-pixel dark/flat calibrated aperture photometry: radius 5 px (~15.8 arcsec), sky annulus 12-18 px; checked at 7/9 px and with an independent ensemble. Clouds/uncertain intervals excluded. Satellite-trail affected comparison measurements masked; target aperture unaffected.
Empirical check-star uncertainty (mag), in file row order: 0.0672, 0.0395, 0.0395, 0.0395, 0.0395, 0.0395, 0.0395, 0.0395, 0.0674, 0.0673, 0.0566, 0.0505, 0.0467, 0.0395.
Finding-chart labels below map local field IDs to Gaia DR3 source IDs. Gaia magnitudes identify stars only, not narrowband calibration. C=comparison ensemble; K=independent checks.
C: 828=181924987776412032, 2069=181904818609997568, 2048=182124278554551808, 483=182124381633760384, 1816=181532187246360192, 1488=181914061379613440, 794=181920628384666496, 2027=181915680582371584, 751=181859021373889664, 1131=181531568771070592, 1802=181903341138928000, 1445=181956358216236416, 667=181529889439234816, 411=181527651760898432, 883=181944778984398208, 461=181863934816447744, 1466=181867847531508736, 381=181864450212510720, 1841=182149704760896128, 1876=181938873405714816.
K: 1338=181962061932803456, 682=181938598527811712, 1618=182150323236181120, 2003=181852527383372032, 1144=182151177931992320, 684=181939079564130816, 806=181853145858644352, 442=181477937515914368, 2248=181941931422379392, 818=182151796407282560, 1120=181861804512632704, 1261=181851427871877120, 591=181476150808390912, 808=181852733541800320, 2078=181940724536592640, 620=181841600986534400, 532=182154893081375232, 1087=181947527763469824, 584=182167640544313344, 1368=182152689760476416.
Oct 17 shows a likely secondary eclipse. No precision minimum, period change or discovery is claimed. Raw frames, calibrations, rich CSVs and full reduction provenance are retained.
Determined minima
  • S: 2461330.875940 (10/17/2026, 09:01 UTC)
    HJDmin: 2461330.879073 +/- 0.002990  
    Heliocentric correction: 0.003133
    Data quality: 5 (poor)
    Created by: Filip Walter (10/21/2026, 09:12 UTC)
    Note: 
    CL Aur, 2026-10-17 UTC; 14 retained exposures through H-alpha. Optolong 1.25-inch narrowband filter; nominal FWHM 7 nm (HASIIOIII-125 set). JD values are UTC exposure midpoints, uncorrected (not HJD/BJD). Relative ensemble magnitudes: this target's Oct 18 median is set to zero separately in each filter. This reference level is not a verified out-of-eclipse maximum; these are not standard magnitudes. Filters must remain separate.
Native-pixel dark/flat calibrated aperture photometry: radius 5 px (~15.8 arcsec), sky annulus 12-18 px; checked at 7/9 px and with an independent ensemble. Clouds/uncertain intervals excluded. Satellite-trail affected comparison measurements masked; target aperture unaffected.
Empirical check-star uncertainty (mag), in file row order: 0.0672, 0.0395, 0.0395, 0.0395, 0.0395, 0.0395, 0.0395, 0.0395, 0.0674, 0.0673, 0.0566, 0.0505, 0.0467, 0.0395.
Finding-chart labels below map local field IDs to Gaia DR3 source IDs. Gaia magnitudes identify stars only, not narrowband calibration. C=comparison ensemble; K=independent checks.
C: 828=181924987776412032, 2069=181904818609997568, 2048=182124278554551808, 483=182124381633760384, 1816=181532187246360192, 1488=181914061379613440, 794=181920628384666496, 2027=181915680582371584, 751=181859021373889664, 1131=181531568771070592, 1802=181903341138928000, 1445=181956358216236416, 667=181529889439234816, 411=181527651760898432, 883=181944778984398208, 461=181863934816447744, 1466=181867847531508736, 381=181864450212510720, 1841=182149704760896128, 1876=181938873405714816.
K: 1338=181962061932803456, 682=181938598527811712, 1618=182150323236181120, 2003=181852527383372032, 1144=182151177931992320, 684=181939079564130816, 806=181853145858644352, 442=181477937515914368, 2248=181941931422379392, 818=182151796407282560, 1120=181861804512632704, 1261=181851427871877120, 591=181476150808390912, 808=181852733541800320, 2078=181940724536592640, 620=181841600986534400, 532=182154893081375232, 1087=181947527763469824, 584=182167640544313344, 1368=182152689760476416.
Oct 17 shows a likely secondary eclipse. No precision minimum, period change or discovery is claimed. Raw frames, calibrations, rich CSVs and full reduction provenance are retained.
Actions:
Light curve
Field identification - Star field chart
Chart - CL Aur, JD 2461330.76674
Field identification - Explicitly named stars

No comparison or check stars are explicitly listed for this observation. They should be marked in the star field chart.

Comments