Star Vetter

TIC 336181565

An uncatalogued eclipsing-binary candidate from TESS.

Period aliasSurvivorP = 2.15754 d

Eclipsing-binary candidate: 2.1575-day period (twice the BLS period), a 4.51% primary eclipse, a 2.84% secondary eclipse at phase 0.506.

Primary eclipsetotal light 0.956
Surface brightness ratio
0.63
Companion / star radius
~0.22
Face hidden at primary eclipse
~5%
Separation
~10.0 x the star's radius
Eccentricity
consistent with circular
Secondary eclipse phase
0.506 measured, 0.500 in this orbit

Zoomed: both stars drawn about 2x 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 7,767x 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 09:08 UTC
  • Secondary2026-10-20 11:20 UTC
  • Primary2026-10-21 12:55 UTC

Computed from the fitted ephemeris. Approximate - not corrected for your location or for light-travel time across Earth's orbit.

I

The signal

A repeating, consistent dip in brightness.

observed binned median residuals
0.940.960.981.001.021.040-0.4-0.20.00.20.4phase (P = 2.1575 d)relative flux

Residual scatter 121381793721803.813% (observed minus binned median).

!

Alternate eclipses differ in depth, so the true period is twice the search period.

Period
2.15754 d
Primary depth
4.51%
Secondary depth
2.84%
Epoch (T0)
1597.116 BTJD
Duration
2.02 h
II

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
III

The pixel check

Confirms the dimming is on the target star, not a nearby source.

Out of eclipse
In eclipse
Difference (out - in)
+ target TIC 336181565x neighbour bright enough to cause the dipo other TIC starsO dimming centroid1 pixel = 21"

Out/in share one sqrt colour scale; in-eclipse = out-of-eclipse minus difference. TESS sector 11.

30.2
0.17 px4"
-0.0100 phase
TIC 9625355420.29 px, dT 3.3
0.90
11

The dimming is centred on the target star. No nearby contaminant detected.

Centroid offset
0.17 px
Difference SNR
30.2
Capable neighbour
TIC 962535542
TESS sector
11
IV

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.

V

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.

VI

Fold it yourself

Adjust the period and watch the eclipse appear.

0.940.960.981.001.021.04-0.4-0.20.00.20.4phaserelative flux
2.15754

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
2.15754 d
BLS period
1.07877 d
Odd/even z
4.52
VII

Caveats

Known limitations and things to check.

  • Period alias:Odd/even eclipse-depth z-score is 4.52 (gate > 3.0): alternating eclipses differ significantly in depth, the signature of a true period double what BLS found. Pixel-check confirmation and eclipse timing are unaffected - report the corrected period, 2.157543 d, in any write-up.
VIII

Instrument

Raw values, fits and technical details.

Show raw data

Full statistics

2.15754 d
1.07877 dalias
4.51% +/- 0.47%seen 4/7
ML screening score
0.239logistic_regression
2.84% +/- 0.28%phase 0.506, 10 sigma
4.52> 3: alias
13.5313 dpower 0.01
2.0 h
Distance (TIC, Gaia-based)
1029 pc
15.44 / 14.85
- / -
RA / Dec (J2000)
13h 03m 15.3s -66d 26m 42s
132.4 / 30.2
1,081 ptsover 27 d

Eclipse close-ups

Primary eclipse4.51%
0.940.960.981.001.021.04-6-4-20246hours from mid-eclipse
Secondary (phase 0.506)2.84%
0.940.960.981.001.021.04-6-4-20246hours from mid-eclipse

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

BLS period 1.0788 d
0.940.960.981.001.021.04-0.50.00.5
2x BLS 2.1575 d
0.940.960.981.001.021.04-0.50.00.5

Odd/even depth z = 4.52 (gate 3.0): alternate eclipses differ, so the true period is 2 x 1.0788 = 2.1575 d.

O - C timing

primary eclipses
only 0 fully-covered eclipse(s) in the data - at least 3 are needed to test the period for timing changes

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