TIC 330739083

TYC 3986-1685-1 · Gaia DR3 2005897340986880640 · an A2 spectroscopic binary

Position: 22h 16m 29.87s, +55° 10′ 16.0″
V magnitude: 11.31
Where: 35 arcmin northwest of V345 Lac
Signal: EA, primary only in the TESS data. About 5.5 to 6.3 percent. No secondary eclipse in the phase fold.

What TESS shows

Gaia already published this star as a single-lined spectroscopic binary, period 7.62189 ± 0.00256 days. It was not catalogued as an eclipsing binary. Eighteen TESS eclipses, in sectors 56, 57, 76, 77, 83, and 84, fall on that orbit. The photometric epoch used in the note is the first clean minimum:

T0 = 2828.323 BTJD, P = 7.62189 d

The TESS eclipses are spaced by about 7.625 days, which matches the Gaia period inside the binning. No secondary eclipse shows up in the phase fold. The depth is 5.5 to 6.3 percent. No centroid test has been done. The adopted period is the Gaia period. By late 2026 the 0.003-day difference between that period and the raw TESS spacing has grown to about half a day, so the times below are a window.

The light curves

TESS sectors. The lines mark the eclipse times on the Gaia period.

Phase fold on the Gaia period, 7.62189 days.

Finder chart

Real sky images (DSS2 red) with Gaia DR3 stars overlaid. North is up, east is left, J2000. Red tick marks point at the target (Gaia DR3 2005897340986880640, G = 11.37). Gold squares C1 to C5 are comparison stars of similar brightness. Tap an image for the full-size printable chart.

Wide finder, 30 × 30 arcmin, for star-hopping.

Close finder, 8 × 8 arcmin, to pick out the target.

	Gaia DR3	RA, Dec (J2000)	G	BP	RP	From target
C1	2005897787663468160	22:16:41.6 +55:13:28.6	11.89	12.06	11.57	3.6′
C2	2005849370477552640	22:16:53.4 +55:07:10.4	12.06	12.39	11.56	4.6′
C3	2005896928670045184	22:17:06.9 +55:11:26.8	11.05	11.36	10.57	5.4′
C4	2005900880039906176	22:16:35.7 +55:16:19.0	12.15	12.55	11.58	6.1′
C5	2005850027629284224	22:17:15.7 +55:11:40.1	10.43	10.52	10.20	6.7′

Comparison stars are within about 1 mag of the target in Gaia G, have similar color, no close companion, and no VSX entry within 10 arcsec. Images: DSS2 red (POSS-II, STScI Digitized Sky Survey). Stars: ESA Gaia DR3.

VSX

Submitted to VSX on 9 October 2026. It is in review under the name TIC 330739083. This was the first star filed from a new account, so the others wait until a moderator accepts it.

Next two eclipses

Eclipse 1The two period clocks for cycle 199 disagree, so treat this as a window, not a minute.Earlier clock: 31 Oct 2026, 13:48 UTC · 31 Oct, 06:48 PDT Pacific · 31 Oct, 14:48 CET central EuropeLater clock: 1 Nov 2026, 04:40 UTC · 31 Oct, 21:40 PDT Pacific · 1 Nov, 05:40 CET central Europe
Eclipse 2The two period clocks for cycle 200 disagree, so treat this as a window, not a minute.Earlier clock: 8 Nov 2026, 04:44 UTC · 7 Nov, 20:44 PST Pacific · 8 Nov, 05:44 CET central EuropeLater clock: 8 Nov 2026, 19:40 UTC · 8 Nov, 11:40 PST Pacific · 8 Nov, 20:40 CET central Europe

Watch the whole window, not one of the two clocks. The eclipse depth is about 6 percent. I do not have a measured duration to quote. No centroid test has been done.

Help with a measurement

A ground eclipse tells us the dip is on this star and not on a neighbor in the TESS pixel. Differential photometry is the right tool. Pick a date if you can try.

The note

Eclipses of the Gaia Spectroscopic Binary TIC 330739083 (PDF)

These pages use the public TESS Quick-Look Pipeline and catalog positions. A prediction is not a confirmation. If you observe, write down which star was in the aperture.