ExoClock

The Star
Simbad GAIA 2MASS	K2-25 DR2 3311804515502788352 J04130560+1514520
RA	04:13:05.6134		DEC	+15:14:52.013
Parallax 22.215 mas		P.M. RA 122.148 mas/y		P.M. DEC -18.337 mas/y
Mag_V 15.56	Mag_R 13.72	Mag_I^* 12.569	Mag_J 11.303	Mag_H 10.732	Mag_K 10.444
Mag_G 14.382		Mag_{G_BP} 16.075		Mag_{G_RP} 13.12
^*Calculated from GAIA magnitudes.

Ephemeris - Verified
Kokori et al. 2025
Mid-time 2457714.193756 ± 5.6e-05 BJD_TDB
Period 3.48456287 ± 3.8e-07 days
Transit Parameters
Mann et al. 2016
R_p/R_s^** 0.1037 ± 0.0023	a/R_s^** 25.1 +4.1 -4.1		i 88.3 +1.2 -0.7 deg
R_p/R_s^** 0.1037 ± 0.0023	e 0.27 +0.16 -0.21		ω 62.0 +44.0 -39.0 deg
Depth_R^* 13.39 mmag		Duration^* 0.79 hours
^Calculated from the other parameters, using PyLightcurve. ^*Adjusted based on the space observations.
Limb Darkening Parameters
Mann et al. 2016
T_eff 3180.0 +60.0 -60.0 K	Log(g) 4.98 +0.07 -0.07 cm/s²		Fe/H 0.15 +0.03 -0.03 dex

ExoClock Status
Observing Priority		LOW
Minimum aperture		14.3"
Total Observations (Recent)		72 (3)
O-C		-0.54 ± 0.97 minutes
ExoClock Observations (Recent)		17 (3)
Space Observations (Recent)		18 (0)
ETD Observations (Recent)		0 (0)
Literature Mid-times (Recent)		37 (0)
Kepler R_p/R_s		-
TESS R_p/R_s		0.1037 ± 0.0023

Planet Observation Date	Observer Observatory	Telescope Camera / Filter / Exp [s]	O-C minutes
ExoClock Observations
K2-25b (LOW) 2025-12-01	Michael Nezel Celle Observatory	CDK 14 QHY 268M / I / 60.0	-4.08 ± 3.6
K2-25b (LOW) 2025-10-16	Alexey Garmash Lyceum 130	EdgeHD C11 ASI2600MM pro / ipr / 240.0	0.27 ± 1.44
K2-25b (LOW) 2025-02-28	Yves Jongen Rasteau Observatory	Plane Wave CDK 17" SBIG STXL 11002 / Lum / 120.0	-0.52 ± 1.73
K2-25b (LOW) 2025-02-14	Mario Morales-Aimar Observatorio de Sencelles MPC K14	Reflector 10" SBIG ST7-XME / Clear / 180.0	-1.31 ± 2.45
K2-25b (LOW) 2024-01-14	Lee YuHsien KMSH Observatory	C14HD QSI-660 / Clear / 60.0	-1.07 ± 2.3
K2-25b (LOW) 2023-11-19	Mario Morales-Aimar Observatorio de Sencelles MPC K14	Reflector 10" SBIG ST7-XME / Clear / 150.0	-0.2 ± 2.74
K2-25b (LOW) 2023-11-05	Nataliia Maslennikova Caucasus Mountain Observatory SAI MSU	RC-600 ASA Andor iKon-L / ipr / 60.0	0.92 ± 0.89
K2-25b (LOW) 2023-10-16	Nataliia Maslennikova Caucasus Mountain Observatory SAI MSU	RC-600 ASA Andor iKon-L / ipr / 120.0	0.93 ± 0.66
K2-25b (LOW) 2023-10-09	Alvaro Fornas MPC J57. Centro Astronómico Alto Turia	Planewave CDK 17 QHY600M / Lum / 180.0	3.48 ± 2.16
K2-25b (LOW) 2023-09-25	Alvaro Fornas MPC J57. Centro Astronómico Alto Turia	Planewave CDK 17 QHY600M / Lum / 180.0	2.69 ± 1.44
K2-25b (LOW) 2022-12-16	Martin Crow Burnham Observatory	Celestron C9.25 SX694 mono / Clear / 150.0	-0.2 ± 2.02
K2-25b (LOW) 2022-01-26	Jacques Michelet Claix	GSO Ritchey-Chrétien QSI-632 / R / 180.0	-1.86 ± 3.02
K2-25b (LOW) 2021-12-22	Carole Haswell OSO PIRATE	PlaneWave Instruments CDK24 24 inch (610 mm) f/6.5 Corrected Dall-Kirkham Astrograph FLI ProLine KAF-16803 / R / 60.0	0.34 ± 4.32
K2-25b (LOW) 2021-10-17	Taewoo Kim Deokheung Optical Astronomy Observatory	NYSC 1m Telescope FLI PL-16803 or PI SOPHIA-2048B / R / 60.0	-1.69 ± 1.3
K2-25b (LOW) 2021-01-08	Taewoo Kim Deokheung Optical Astronomy Observatory	NYSC 1m Telescope FLI PL-16803 or PI SOPHIA-2048B / I / 60.0	-0.26 ± 0.58
K2-25b (LOW) 2020-12-25	Taewoo Kim Deokheung Optical Astronomy Observatory	NYSC 1m Telescope FLI PL-16803 or PI SOPHIA-2048B / I / 60.0	0.68 ± 0.72
K2-25b (LOW) 2020-12-04	Taewoo Kim Deokheung Optical Astronomy Observatory	NYSC 1m Telescope FLI PL-16803 or PI SOPHIA-2048B / R / 90.0	0.07 ± 1.3
Space Observations
Planet Observation Date	Mission		O-C minutes
K2-25b (LOW) 2023-11-09	TESS		-3.82 ± 3.46
K2-25b (LOW) 2023-11-05	TESS		0.74 ± 1.44
K2-25b (LOW) 2023-11-02	TESS		-1.03 ± 1.02
K2-25b (LOW) 2023-10-26	TESS		2.74 ± 5.04
K2-25b (LOW) 2023-10-19	TESS		4.79 ± 3.74
K2-25b (LOW) 2023-10-12	TESS		-0.5 ± 1.73
K2-25b (LOW) 2023-10-09	TESS		-3.0 ± 2.02
K2-25b (LOW) 2023-10-05	TESS		0.98 ± 2.16
K2-25b (LOW) 2023-10-02	TESS		-0.09 ± 1.58
K2-25b (LOW) 2023-09-28	TESS		0.15 ± 1.87
K2-25b (LOW) 2023-09-25	TESS		-2.51 ± 1.2
K2-25b (LOW) 2023-09-21	TESS		0.62 ± 2.02
K2-25b (LOW) 2021-11-04	TESS		1.46 ± 1.87
K2-25b (LOW) 2021-10-31	TESS		1.7 ± 1.87
K2-25b (LOW) 2021-10-28	TESS		-0.65 ± 1.41
K2-25b (LOW) 2021-10-21	TESS		0.53 ± 1.44
K2-25b (LOW) 2021-10-17	TESS		5.37 ± 3.74
K2-25b (LOW) 2021-10-14	TESS		-2.32 ± 3.89
Literature Mid-times
Planet Observation Date	Reference		O-C minutes
2017-05-11	Kain et al. 2020		0.16 ± 0.26
2017-01-02	Kain et al. 2020		0.09 ± 0.2
2016-12-30	Kain et al. 2020		0.21 ± 0.27
2016-12-26	Kain et al. 2020		-0.53 ± 0.25
2016-12-23	Kain et al. 2020		-0.16 ± 0.24
2016-12-19	Kain et al. 2020		0.55 ± 0.3
2016-12-12	Kain et al. 2020		0.36 ± 0.25
2016-12-09	Kain et al. 2020		0.93 ± 0.98
2016-12-09	Kain et al. 2020		-1.09 ± 0.23
2016-12-05	Kain et al. 2020		-0.1 ± 0.24
2016-12-02	Kain et al. 2020		0.2 ± 0.29
2016-11-28	Kain et al. 2020		0.25 ± 0.22
2016-11-25	Kain et al. 2020		-0.01 ± 0.25
2016-11-18	Kain et al. 2020		0.22 ± 0.28
2016-11-11	Kain et al. 2020		-0.47 ± 0.27
2016-11-04	Kain et al. 2020		-0.32 ± 0.37
2016-10-28	Kain et al. 2020		0.02 ± 0.33
2016-10-21	Kain et al. 2020		-0.25 ± 0.33
2016-10-14	Kain et al. 2020		-0.11 ± 0.29
2016-10-07	Kain et al. 2020		-0.23 ± 0.5
2015-12-16	Kain et al. 2020		-0.01 ± 0.39
2015-12-09	Kain et al. 2020		0.26 ± 0.25
2015-04-19	Kain et al. 2020		-0.47 ± 0.68
2015-04-12	Kain et al. 2020		-1.44 ± 0.42
2015-04-09	Kain et al. 2020		2.24 ± 0.8
2015-04-05	Kain et al. 2020		0.93 ± 0.5
2015-04-02	Kain et al. 2020		-1.33 ± 0.64
2015-03-29	Kain et al. 2020		1.28 ± 0.55
2015-03-22	Kain et al. 2020		0.31 ± 0.56
2015-03-15	Kain et al. 2020		-0.62 ± 0.53
2015-03-01	Kain et al. 2020		-0.5 ± 0.56
2015-02-26	Kain et al. 2020		0.68 ± 0.53
2015-02-23	Kain et al. 2020		-1.07 ± 0.47
2015-02-19	Kain et al. 2020		1.6 ± 0.56
2015-02-16	Kain et al. 2020		-1.78 ± 0.54
2015-02-12	Kain et al. 2020		1.46 ± 0.49
2015-02-09	Kain et al. 2020		2.22 ± 0.5

K2-25b (LOW)

Discovered by: Mann et al. 2016

ExoClock Observations

Space Observations

Literature Mid-times