exoclock

HAT-P-28b (LOW)

Discovered by: Buchhave et al. 2011

The Star
Simbad
GAIA
2MASS		 HAT-P-28
DR2 363702817083391232
J00520018+3443422
RA 00:52:00.1877 DEC +34:43:42.203
Parallax
2.463 mas		 P.M. RA
25.519 mas/y		 P.M. DEC
2.859 mas/y
MagV
13.03		 MagR
13.24		 MagI*
12.142		 MagJ
11.561		 MagH
11.206		 MagK
11.104
MagG
12.872		 MagGBP
13.3		 MagGRP
12.275
*Calculated from GAIA magnitudes.

Ephemeris - Verified True
Kokori et al. 2025
Mid-time
2458971.21837 ± 0.0002 BJDTDB
Period
3.25721269 ± 5e-07 days
Transit Parameters
Buchhave et al. 2011
Rp/Rs
0.113 ± 0.0024		 a/Rs
8.4 +0.6 -0.6
 i
88.0 +0.9 -0.9 deg
e
0.05 +0.03 -0.03
 ω
233.0 +90.0 -90.0 deg
DepthR*
16.75 mmag		 Duration*
3.31 hours
*Calculated from the other parameters, using PyLightcurve.
**Adjusted based on the space observations.

Limb Darkening Parameters
Buchhave et al. 2011
Teff
5680.0 +90.0 -90.0 K
 Log(g)
4.36 +0.06 -0.06 cm/s2
 Fe/H
0.12 +0.08 -0.08 dex
ExoClock Status
Observing Priority LOW
Minimum aperture 8.59"
Total Observations (Recent) 52 (15)
O-C 0.57 ± 0.38 minutes
ExoClock Observations (Recent) 43 (15)
Space Observations (Recent) 8 (0)
ETD Observations (Recent) 0 (0)
Literature Mid-times (Recent) 1 (0)
Kepler Rp/Rs -
TESS Rp/Rs 0.11117 ± 0.00095

HAT-P-28b


ExoClock Observations
Planet
Observation Date		 Observer
Observatory		 Telescope
Camera / Filter / Exp [s]		 O-C
minutes
HAT-P-28b (LOW)
2025-12-26		Tommaso Dittadi
TD-TRO		Ritchey-Chretien
Moravian G2-1600 / R / 240.0		1.56 ± 1.87
HAT-P-28b (LOW)
2025-11-20		samuel Diaz Lopez
Tomas Lopez (AstroCamp)		SCA260
ASI2600MM / Clear / 164.0		2.19 ± 2.16
HAT-P-28b (LOW)
2025-11-20		Yves Jongen
Rasteau Observatory		Plane Wave CDK 17"
SBIG STXL 11002 / Lum / 180.0		1.47 ± 1.24
HAT-P-28b (LOW)
2025-11-20		John Collins
JC_Wrexham		Meade LX200GPS
ASI-290m / Lum / 120.0		-2.27 ± 1.58
HAT-P-28b (LOW)
2025-10-12		Yves Jongen
Rasteau Observatory		Plane Wave CDK 17"
SBIG STXL 11002 / Lum / 180.0		4.43 ± 2.02
HAT-P-28b (LOW)
2025-09-20		Francesco Scaggiante
Gruppo Astrofili Salese "GALILEO GALILEI"		NEWTON 410/1710
Player One Astronomy Poseidon-M Pro (IMX571) / Clear / 30.0		-3.36 ± 2.59
HAT-P-28b (LOW)
2025-09-07		Pieter Vuylsteke
Marvel (La Palma)		ASA Ritchey
ZWO 6200mm / rpr / 120.0		3.71 ± 1.09
HAT-P-28b (LOW)
2025-09-07		Tommaso Dittadi
TD-TRO		Ritchey-Chretien
Moravian G2-1600 / R / 240.0		-0.26 ± 2.3
HAT-P-28b (LOW)
2025-08-25		Manfred Raetz
privat observatory Herges-Hallenberg		SCT 280/1850 (C11 with Starizona reducer)
Moravian Instruments G2-1600 / AstrodonExoPlanet-BB / 120.0		1.68 ± 1.02
HAT-P-28b (LOW)
2025-08-25		Giovanni Calapai
Home Astronomical Observatory		Celestron 11 Schmidt-Cassegrain
Atik 314L+ / Clear / 90.0		1.25 ± 1.58
HAT-P-28b (LOW)
2025-08-25		Matthieu Bachschmidt
Gonachon		Celestron C11
SBIG ST8XME / AstrodonExoPlanet-BB / 150.0		0.38 ± 1.73
HAT-P-28b (LOW)
2025-08-25		Lionel Rousselot
Private observatory Vierzon		Newton 250/740
ZWO 533 monochrome / Lum / 180.0		0.1 ± 1.73
HAT-P-28b (LOW)
2025-08-25		Gerold Holtkamp
Gerold Holtkamp		Newtonian
QHY268M / Lum / 60.0		0.1 ± 1.44
HAT-P-28b (LOW)
2025-08-25		Adrian Jones
Private Observatory (I64)		Meade ACF 30cm
QSI 583 / Lum / 150.0		-1.78 ± 1.58
HAT-P-28b (LOW)
2025-08-11		Yves Jongen
Rasteau Observatory		Plane Wave CDK 17"
SBIG STXL 11002 / Lum / 180.0		-1.99 ± 1.87
HAT-P-28b (LOW)
2024-11-17		Yves Jongen
Rasteau Observatory		Plane Wave CDK 17"
SBIG STXL 11002 / Lum / 180.0		0.95 ± 1.87
HAT-P-28b (LOW)
2024-08-31		Yen-Hsing Lin
Starry House Observatory		Mewlon 300 CRS
ASI 6200MM Pro / Lum / 60.0		-5.09 ± 1.58
HAT-P-28b (LOW)
2023-12-11		Snaevarr Guðmundsson
Ness Observatory		Meade LX 200 ACF Schmidt-Cassegrain
SBIG STL 11000M / AstrodonExoPlanet-BB / 120.0		0.5 ± 1.14
HAT-P-28b (LOW)
2023-11-28		Martin Crow
Burnham Observatory		Celestron C9.25
SX694 mono / R / 200.0		-1.09 ± 2.45
HAT-P-28b (LOW)
2023-11-15		Anaël Wünsche
Observatoire des Baronnies Provençales		CDK Planewave 2
ZWO ASI6200 / V / 120.0		0.77 ± 1.37
HAT-P-28b (LOW)
2023-11-15		Marco Stefanini
Osservatorio Aldebaran		Celestron C14
QHY294M Pro / Lum / 150.0		-0.59 ± 1.58
HAT-P-28b (LOW)
2023-11-15		Mark Salisbury
POST		Orion Optics ODK
SBIG ST-10 XME / Clear / 240.0		-2.27 ± 0.91
HAT-P-28b (LOW)
2023-10-14		Charles Miller
Miller Observatory		Meade 12" LX850
QHY268M / R / 60.0		3.05 ± 1.58
HAT-P-28b (LOW)
2023-09-14		Manfred Raetz
privat observatory Herges-Hallenberg		SCT 280/1850 (C11 with Starizona reducer)
Moravian Instruments G2-1600 / AstrodonExoPlanet-BB / 120.0		-0.31 ± 1.37
HAT-P-28b (LOW)
2023-09-14		Martin Crow
Burnham Observatory		Celestron C9.25
SX694 mono / Clear / 240.0		-0.53 ± 1.73
HAT-P-28b (LOW)
2023-07-15		Gemma Domènech
Observatori Astronòmic Albanyà		Meade ACF F8
Moravian G4-9000 / I / 160.0		0.11 ± 2.3
HAT-P-28b (LOW)
2022-12-08		Adrian Jones
Private Observatory (I64)		Meade ACF 30cm
QSI 583 / R / 200.0		-0.71 ± 1.41
HAT-P-28b (LOW)
2022-10-07		Marco Bastoni
Bellatrix		GSO RC 10''
Moravian G3-16200 / Lum / 300.0		-0.77 ± 4.32
HAT-P-28b (LOW)
2022-07-25		Yves Jongen
Rasteau Observatory		Plane Wave CDK 17"
SBIG STXL 11002 / Lum / 180.0		1.38 ± 1.3
HAT-P-28b (LOW)
2022-01-13		Adrian Jones
Private Observatory (I64)		Meade ACF 30cm
QSI 583 / R / 150.0		2.89 ± 2.59
HAT-P-28b (LOW)
2022-01-13		Paolo Arcangelo Matassa
P:M.P.H.R. Deep Sky (K81)		Ritchey Chretien 40cm-F5.3
CCD ICX453AQ / Lum / 120.0		-1.43 ± 4.32
HAT-P-28b (LOW)
2021-10-17		Adrian Jones
Private Observatory (I64)		Meade ACF 30cm
QSI 583 / R / 200.0		1.08 ± 4.32
HAT-P-28b (LOW)
2020-11-13		Mike Miller
Georgetown Observatory		Meade 10 inch ACF f8 f5.6
QSI 540 / V / 120.0		2.69 ± 5.76
HAT-P-28b (LOW)
2020-09-22		Manfred Raetz
privat observatory Herges-Hallenberg		SCT 280 /1790 (Celestron C11 with reducer)
Moravian Instruments G2-1600 / Clear / 120.0		-2.49 ± 1.15
HAT-P-28b (LOW)
2020-09-09		Manfred Raetz
privat observatory Herges-Hallenberg		SCT 280 /1790 (Celestron C11 with reducer)
Moravian Instruments G2-1600 / Clear / 120.0		2.34 ± 0.86
HAT-P-28b (LOW)
2020-08-26		Dim Stouraitis
Galilaios		SCT
SXVF-H9 Starlight-Xpress / R / 70.0		0.25 ± 1.73
HAT-P-28b (LOW)
2019-12-03		Anaël Wünsche
Observatoire des Baronnies Provençales		Astelco
FLIPL230 / Clear / 60.0		-2.72 ± 0.86
HAT-P-28b (LOW)
2019-10-25		Nikolaos Paschalis
Nunki Observatory		Officina Stellare RILA 400
SBIG STXL 11002 / R / 60.0		0.53 ± 3.17
HAT-P-28b (LOW)
2019-10-02		Yves Jongen
Rasteau Observatory		Plane Wave CDK 17"
SBIG STXL 11002 / Clear / 120.0		1.66 ± 1.58
HAT-P-28b (LOW)
2018-12-26		Yves Jongen
Rasteau Observatory		Plane Wave CDK 17"
SBIG STXL 11002 / Clear / 120.0		1.36 ± 1.44
HAT-P-28b (LOW)
2018-10-12		Anaël Wünsche
Observatoire des Baronnies Provençales		Astelco
FLIPL230 / Clear / 60.0		0.63 ± 0.58
HAT-P-28b (LOW)
2018-09-29		Marc Deldem
Les Barres Observatory		Celestron C8
SBIG ST8-XME / Clear / 120.0		0.99 ± 3.17
HAT-P-28b (LOW)
2017-11-17		Anaël Wünsche
Observatoire des Baronnies Provençales		Astelco
FLIPL230 / Lum / 120.0		-0.55 ± 1.15

Space Observations
Planet
Observation Date		 Mission O-C
minutes
HAT-P-28b (LOW)
2022-10-27		TESS3.73 ± 1.58
HAT-P-28b (LOW)
2022-10-24		TESS1.2 ± 1.41
HAT-P-28b (LOW)
2022-10-20		TESS-1.99 ± 1.73
HAT-P-28b (LOW)
2022-10-17		TESS2.17 ± 1.34
HAT-P-28b (LOW)
2022-10-14		TESS-1.61 ± 1.31
HAT-P-28b (LOW)
2022-10-07		TESS1.53 ± 1.58
HAT-P-28b (LOW)
2022-10-04		TESS0.54 ± 1.58
HAT-P-28b (LOW)
2022-10-01		TESS-0.72 ± 1.43

Literature Mid-times
Planet
Observation Date		 Reference O-C
minutes
2010-08-09 Buchhave et al. 2011 -0.34 ± 0.76
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