TIC 104517577

Transit candidateNotable, 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 HD 189943 (*); catalogued variable star nearby: Gaia DR3 2030252927983885952 (ROT), 72" away. The rare-find check confirms what is on record - still nice, but not a new discovery.

Transits of a giant star notable
Gaia places this star among the giants: planets transiting giants are rare, and a big star makes even a large planet's dip tiny.

Checked, nothing found (7)

Microlensing (rogue planet?) · Exocomet-shaped dip · Habitable zone & size · Transit timing (TTV) · Transit duration (TDV) · Changing transit depth · Lopsided transit

Checked 2026-10-11 16:26 on NVIDIA GeForce RTX 4070, using every TESS sector of this star. All results (.json)

Notes

Probably noise or an instrument effect. Notable, already known: Transits of a giant star (in SIMBAD as HD 189943 (*); catalogued variable star nearby: Gaia DR3 2030252927983885952 (ROT), 72" away). Found automatically by hunt.py in TESS sector 14 (flagged in 1 sector(s)). Detection score 327.7. 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: 2026-10-11 Planet check: Probably noise or an instrument effect 2026-10-11 Rare-find check: Transits of a giant star 2026-10-09 Gaia hints at a hidden companion star (RUWE 3.0) 2026-10-09 Found by the automatic search in TESS sector 14

The signal

Type	Transit candidate
Status	Notable, already known
Period (days)	1.0916
Period source	hunt.py on TESS QLP sector 14
Eclipse / dip depth	0.9%
Amplitude	1.0%
Data used	TESS sector 14 (QLP)

Planet check

Verdict	Probably noise or an instrument effect ExoFOP check plot all test results light curve data
Size if it's a planet	~132.4 Earth radii (~11.81 Jupiter) - too big for a planet

The star (Gaia & TESS)

Distance (pc)	308 (~1,003 light years)
Colour, Gaia BP-RP	1.02
RUWE (Gaia)	3.03 - hints at a hidden companion star
Gaia G mag	7.52
TESS mag	6.975

Names & neighbours

TIC ID	104517577
Gaia DR3 ID	2030252966675711872
SIMBAD name	HD 189943 [*]
Nearest known variable	Gaia DR3 2030252927983885952 (ROT), 72" away
RA (deg)	300.382
Dec (deg)	30.2181
Look it up	SIMBAD · VSX · ESASky · ExoFOP

Record

Found by	hunt.py (automatic)
Date	2026-10-09
Last update	2026-10-11

Where it sits among the stars

ESA Gaia colour and true brightness. Grey: every Star Log candidate. Orange: this star.

How to read this diagram →

Data files

Download everything (.zip)