TESS data show a 275 s decrease in the interval from primary to secondary eclipse of GG Orionis from 2018–2019 to 2025–2026
We measured eclipse times of GG Orionis in public TESS data from Sectors 6 and 98. Two complete pairs from 2018–2019 give a mean interval from primary to secondary eclipse of 2.79072133 days. Three pairs from 2025–2026 give 2.78753816 days. The interval decreased by 275.0 seconds over 6.95 years. The formal fit error is 3.2 seconds. Tests with blocks of residuals give conditional errors of 3.8 to 4.6 seconds. Changes in aperture, flux product, baseline, window, and profile give decreases of 272.9 to 279.4 seconds. A fixed eccentric orbit injected at the actual timestamps gives a sampling and profile bias of 0.1 seconds. With fixed eccentricity 0.2218 and inclination 89.30 degrees, the measured change implies apsidal advance of about 0.000615 degrees per cycle. The earlier measured rate predicts a 272.7-second decrease. The data agree with known apsidal advance. Two visits do not uniquely identify the cause or isolate a relativistic term. We preserve 17 eclipse times, the original data, target time corrections, all analysis choices, figures, and code for an offline repeat.
GG Orionis · TESS · eclipsing binaries · apsidal motion · eclipse times · public data · reproducible astronomy
References
5- usesdoi:10.1051/0004-6361/202040004
We use the published period, orbit parameters, and comparison rates. We extend the Sector 6 timing record with Sector 98 data.
- supportsdoi:10.1086/316855
This earlier study detected apsidal advance in GG Orionis.
- usesdoi:10.1117/1.JATIS.1.1.014003
We use public observations from the TESS mission.
- usesdoi:10.1117/12.2233418
We use the Sector 6 SPOC light curve.
- usesdoi:10.1086/683602
We use batman to calculate exposure-integrated timing profiles and a fixed-orbit control.
Cited by
4 publicationsPublic catalog entries on Sciscape.
- supportsA common profile fit gives a 272-second eclipse spacing decrease in GG Orionis between TESS sectors 6 and 98
A separate reduction of the same observations supports the reported spacing decrease. We also use and preserve its published timing table for an estimator comparison. Errors from the two reductions can be correlated.
- A local period scale reduces the effect of time coordinates below 0.1 s in 12 GG Orionis eclipses from TESS Sector 98
[Legacy relation: reproduces] Our independent spline analysis reproduces the decrease in GG Orionis eclipse spacing between the same TESS visits. That detection preceded this study.
- usesA local period scale reduces the effect of time coordinates below 0.1 s in 12 GG Orionis eclipses from TESS Sector 98
We reuse the two unchanged JPL Horizons response files and preserve their original provenance and hashes. We do not reuse its source code.
- The QLP small aperture to image depth ratio increases by 38% between two GG Orionis secondary eclipses in TESS Sector 98
This prior study reported eclipse spacing changes in the same GG Orionis observations. We do not claim a new timing result.
- usesHalf-depth widths do not clearly separate two orbit models at fixed stellar geometry in 17 TESS eclipses of GG Orionis
We reuse the image extraction and target time code, raw Sector 98 images, saved spacecraft vectors, and provenance. This work already measured the timing change.