TIC 313590380
An uncatalogued eclipsing-binary candidate from TESS.
Eclipsing-binary candidate: 12.4409-day period, a 0.12% primary eclipse, no significant secondary eclipse.
TIC 313590380 is a candidate eclipsing binary star with an orbital period of 12.4409 days, detected through automated analysis of TESS photometry. The primary eclipse produces a dimming of 0.07%, with a detection signal-to-noise ratio of 11.3. No secondary eclipse was detected. Pixel-level image analysis shows a difference-imaging peak signal-to-noise of 6.3, but the centroid offset of 12.3 arcsec from the target raises an important question: TESS's resolution cannot confidently separate this star from a nearby bright neighbor. The centroid measurement falls within the pipeline's stated systematic uncertainty, making it unclear whether the dimming truly originates from the intended target or from the companion star instead. The candidate does not appear in six major variable-star catalogs checked.
- Surface brightness ratio
- companion faint - no secondary eclipse
- Companion temperature
- below ~4,636 K
- Companion / star radius
- ~0.08
- Face hidden at primary eclipse
- ~1%
- Separation
- ~25 x the star's radius
- Eccentricity
- consistent with circular
Zoomed: both stars drawn about 5x larger than their real size relative to the orbit, so they overlap for longer than the real eclipse lasts. A star's surface never gets dimmer during an eclipse - part of it is simply hidden. What drops is the total light we receive, shown exactly by the readout and bar below from the real light curve; the glow dims with it, exaggerated so small dips show. Colours follow temperature on a stellar colour scale, saturated so the differences show; the star's is its catalogue value (4,777 K). The companion's colour, sizes and orbit shape are estimates from the eclipse depths, duration and timing, assuming central eclipses and spherical stars - good to perhaps tens of percent. Only the relative orbit is shown; both stars really circle their common centre of mass. Animated about 44,787x faster than real on average, slowing down through each eclipse, and starting from where the system is in its orbit right now. Hover to pause.
- Primary2026-10-19 15:21 UTC
- Secondary2026-10-25 20:38 UTC
- Primary2026-11-01 01:56 UTC
Computed from the fitted ephemeris. Approximate - not corrected for your location or for light-travel time across Earth's orbit.
The signal
A repeating, consistent dip in brightness.
Residual scatter 0.133% (observed minus binned median).
Clear, repeating eclipses with a consistent period and depth.
- Period
- 12.44090 d
- Primary depth
- 0.12%
- Epoch (T0)
- 2939.759 BTJD
- Duration
- 4.08 h
The catalog check
Cross-matched against known variable-star catalogs to rule out anything already listed.
- VSXNot found
- ASAS-SNNot found
- Gaia eclipsing-binary tableNot found
- Gaia variable classificationNot found
- TESS EB catalog (Prsa+2022)Not found
- ExoFOP TOI listNot found
0/6 catalogs list a known variable at this position.
No known variable star or catalogued match at this position.
- Catalogs checked
- 6
- Matches
- 0
The pixel check
Confirms the dimming is on the target star, not a nearby source.
Out/in share one sqrt colour scale; in-eclipse = out-of-eclipse minus difference. TESS sector 74.
- 6.3
- 0.58 px12"
- 0.0000 phase
- TIC 9508002330.67 px, dT 5.9
- 0.95
- 74
The dimming centroid sits almost as close to a bright neighbour as to the target.
- Centroid offset
- 0.58 px
- Difference SNR
- 6.3
- Capable neighbour
- TIC 950800233
- TESS sector
- 74
The Gaia view
A second spacecraft's measurements: how far away the star is, how bright and what colour, and whether its position fits a single star.
The latest Gaia context file does not include this candidate yet, so there is no Gaia view to show.
The ground-survey check
An independent instrument, different years: does real ZTF photometry show the eclipse at the period TESS measured?
The latest ground-survey file does not include this candidate yet, so there is no independent ZTF check to show.
Fold it yourself
Adjust the period and watch the eclipse appear.
Shown at the true period. The raw light curve needed to re-fold at other periods has not been exported yet - this slider unlocks automatically once it is.
The period the pipeline measured. Drag the slider away from it and the eclipse smears out.
- True period
- 12.44090 d
- BLS period
- 12.44090 d
- Odd/even z
- 0.42
Caveats
Known limitations and things to check.
- Thin margin:The ON_TARGET call rests on a neighbour-competition margin of just 0.089 px (dimming centroid 0.584 px from target vs 0.673 px from the nearest bright-enough neighbour) - inside diag_pixel.py's own stated centroid systematic of 0.10-0.3 px. TESS's resolution cannot confidently separate this star from that neighbour.
VIIIInstrument
Raw values, fits and technical details.
Instrument
Raw values, fits and technical details.
Full statistics
- 12.44090 d
- 12.44090 dsame
- 0.12% +/- 0.02%seen 1/6
- ML screening score
- 0.726logistic_regression
- < 0.11%none at 5 sigma
- 0.42< 3
- 0.4027 dpower 0.01
- 4.1 h
- Distance (TIC, Gaia-based)
- 1490 pc+/- 65
- 11.55 / 10.92
- 4777 K / 10.24 Rsun
- RA / Dec (J2000)
- 13h 19m 12.6s +76d 11m 24s
- 11.3 / 6.3
- 23,434 ptsover 428 d
Eclipse close-ups
Same flux scale on both panels. Line: binned median. Shown in place of an orbit animation - this pipeline measures eclipses, it does not fit an orbit.
Period alias analysis
Odd/even depth z = 0.42 (gate 3.0): alternate eclipses match, so the BLS period stands.