TIC 399581377

Eclipsing binaryNotable, already known

Rare & notable finds

A notable find: not unheard of, but the kind of system astronomers are glad to have more of. How these checks work →

Already known: in SIMBAD as Cl* NGC 1039 W 536 (Pe*); catalogued variable star nearby: NSV 886, 85" away; in the ATLAS variable-star catalogue (Heinze et al. 2018) as J040.0874+42.2449. The rare-find check confirms what is on record - still nice, but not a new discovery.

Eccentric eclipsing binary notable
The second eclipse comes at phase 0.172 instead of 0.5: the orbit is stretched (eccentricity at least 0.516). Eccentric binaries show how tides shape orbits, and their slowly turning orbits test General Relativity.

Checked, nothing found (7)

Microlensing (rogue planet?) · Exocomet-shaped dip · Eclipse timing (third body?) · Eclipses changing depth · Pulsating star in an eclipsing binary · Extra dips outside the eclipses · Type of star

Checked 2026-10-12 17:41 on NVIDIA GeForce RTX 4070, using every TESS sector of this star. All results (.json)

Notes

Notable, already known: Eccentric eclipsing binary (in SIMBAD as Cl* NGC 1039 W 536 (Pe*); catalogued variable star nearby: NSV 886, 85" away). Found automatically by hunt.py in TESS sector 18 (flagged in 1 sector(s)). Detection score 388.3. Not in VSX, ASAS-SN or ZTF variable catalogues at the time of the search; not in Gaia DR3's variable lists. Unchecked by hand yet: verify the period, nearby stars and a wider catalogue search. Updates: 2026-10-12 Rare-find check: Eccentric eclipsing binary 2026-10-10 Found by the automatic search in TESS sector 18

The signal

Type	Eclipsing binary
Status	Notable, already known
Period (days)	2.14586
Period source	hunt.py on TESS QLP sector 18
Eclipse / dip depth	5.0%
Amplitude	4.8%
Data used	TESS sector 18 (QLP)

The star (Gaia & TESS)

Colour, Gaia BP-RP	0.45
Gaia G mag	11.95
TESS mag	11.56

Names & neighbours

TIC ID	399581377
Gaia DR3 ID	337045913583323008
SIMBAD name	Cl* NGC 1039 W 536 [Pe*]
Nearest known variable	NSV 886 (?), 85" away
RA (deg)	40.0874
Dec (deg)	42.245
Look it up	SIMBAD · VSX · ESASky · ExoFOP

Record

Found by	hunt.py (automatic)
Date	2026-10-10
Last update	2026-10-12

Data files

Download everything (.zip)