TIC 233452636
An uncatalogued eclipsing-binary candidate from TESS.
Eclipsing-binary candidate: 1.9063-day period, a 6.55% primary eclipse, no significant secondary eclipse.
- Surface brightness ratio
- companion faint - no secondary eclipse
- Companion / star radius
- ~0.26
- Face hidden at primary eclipse
- ~7%
- Separation
- ~2.3 x the star's radius
- Eccentricity
- consistent with circular
Zoomed: both stars drawn about 0x 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 are illustrative. 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 6,863x 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.
- Secondary2026-10-19 16:16 UTC
- Primary2026-10-20 15:09 UTC
- Secondary2026-10-21 14:01 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 6638560658805213.000% (observed minus binned median).
Clear, repeating eclipses with a consistent period and depth.
- Period
- 1.90632 d
- Primary depth
- 6.55%
- Epoch (T0)
- 1625.249 BTJD
- Duration
- 8.40 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 12.
- 8.9
- 0.08 px2"
- 0.0050 phase
- TIC 13327371740.11 px, dT 3.1
- 1.00
- 12
The dimming centroid sits almost as close to a bright neighbour as to the target.
- Centroid offset
- 0.08 px
- Difference SNR
- 8.9
- Capable neighbour
- TIC 1332737174
- TESS sector
- 12
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.
It is about 15,324 light years away: the light TESS recorded left it around 15,324 years ago.
Together the two stars give off about 24 times the Sun's light in Gaia's band - before correcting for interstellar dust, which only makes distant stars look fainter.
Its colour is redder than the Sun's, which usually means cooler - though dust along the way also reddens light.
Source: ESA Gaia DR3, source 5943526278549226240.
Gaia's position measurements fit this source poorly (RUWE 1.55, above the usual 1.4). That often means more than one star is there - most likely a wider third star or an unresolved neighbour, since a tight eclipsing pair barely moves Gaia's image. Context, not confirmation.
- Distance
- 4,698 +/- 787 pc
- Light-travel time
- ~15,324 years
- Apparent G
- 14.60
- Absolute G
- 1.24
- Colour BP-RP
- 1.88
- RUWE
- 1.55
- Match offset
- 0.10 arcsec
The ground-survey check
An independent instrument, different years: does real ZTF photometry show the eclipse at the period TESS measured?
No ZTF observations at this position (declination -44.3 deg) - likely too far south for ZTF's footprint, which covers the sky north of roughly -31 deg. Not a mark against the candidate, just a gap in ground-survey coverage.
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
- 1.90632 d
- BLS period
- 1.90632 d
- Odd/even z
- 0.02
Caveats
Known limitations and things to check.
- Thin margin:The ON_TARGET call rests on a neighbour-competition margin of just 0.030 px (dimming centroid 0.083 px from target vs 0.113 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
- 1.90632 d
- 1.90632 dsame
- 6.55% +/- 0.38%seen 12/12
- ML screening score
- 0.360logistic_regression
- < 0.84%none at 5 sigma
- 0.02< 3
- 3.2389 dpower 0.02
- 8.4 h
- Distance (TIC, Gaia-based)
- 6121 pc+/- 1760
- 14.61 / 13.87
- - / -
- RA / Dec (J2000)
- 16h 41m 53.5s -44d 20m 44s
- 202.5 / 8.9
- 1,054 ptsover 28 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 = 0.02 (gate 3.0): alternate eclipses match, so the BLS period stands.
O - C timing
12 eclipses timed, rms 118.77 min, reduced chi-square 1423.07 (10 dof): more scatter than the timing errors explain - worth a closer look.
Each eclipse timed by fitting the star's own mean eclipse profile; fitted P = 1.908318 +/- 0.000180 d.