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K2-138 Overview

K2-138 0.86 R⦿ 5281.00 K
K2-138 b
0.135 RJup
K2-138 c
0.205 RJup
K2-138 d
0.213 RJup
K2-138 e
0.302 RJup
K2-138 f
0.259 RJup
K2-138 g
0.269 RJup
Architecture
K2-138
K2-138
K2-138 b
K2-138 c
K2-138 d
K2-138 e
K2-138 f
K2-138 g
Other Data
Bibliography 9
Exoplanet Archive Notes 6
Nearby Data 5
Discovery Data
Host Planet Method Year Reference Disposition
K2-138 K2-138 b Transit 2017 Christiansen et al. 2018 Confirmed Planet
K2-138 K2-138 c Transit 2017 Christiansen et al. 2018 Confirmed Planet
K2-138 K2-138 d Transit 2017 Christiansen et al. 2018 Confirmed Planet
K2-138 K2-138 e Transit 2017 Christiansen et al. 2018 Confirmed Planet
K2-138 K2-138 f Transit 2017 Christiansen et al. 2018 Confirmed Planet
K2-138 K2-138 g Transit 2021 Hardegree-Ullman et al. 2021 Confirmed Planet
K2-138 b K2-138 c K2-138 d K2-138 e K2-138 f K2-138 g
RA
23h15m47.77s
Dec
-10d50m59.06s
Distance
202.585+2.028-1.989
pc
Parallax
4.907950±0.048567 mas
Ecliptic Latitude
-5.61351 deg
Ecliptic Longitude
345.59024 deg
Galactic Latitude
-62.23886 deg
Galactic Longitude
64.21591 deg
Total Proper Motion
10.5710313±0.0816482 mas/yr
Proper Motion (RA)
-1.0180000±0.0835275 mas/yr
Proper Motion (Dec)
-10.5219000±0.0816304 mas/yr
Photometry
mV
12.246±0.092
mTESS
11.5018±0.0068
mJ
10.756±0.021
mH
10.384±0.021
mKs
10.305±0.021
mKep
12.069
mW1
10.274±0.023
mW2
10.332±0.019
mW3
10.279±0.077
mW4
8.84
mGaia
12.025200±0.000364
mB
13.063±0.051
mg
14.8948000±0.0109808
mi
11.8643000±0.0012561
mr
12.0650000±0.0011704
mu
15.0982000±0.0059087
mz
13.0460000±0.0068556
Mission
K2 : Observed in Campaign 12
Tools
ExoFOP Target Overview Page
IRSA Finding Chart
TOI
K2 Names
K2 Planets and Candidates
K2 Targets
Stellar Hosts
K2 Time Series
Source Hardegree-Ullman et al. 2021 Lopez et al. 2019 TICv8 Gaia DR2 Christiansen et al. 2018 ExoFOP-TESS TOI Show Candidate Solutions >> << Hide Candidate Solutions
Teff
(K)
5283+122-163
5356.3+41.8-13.1
5281.000+126.872-130.801
5110.1997+208.5000-53.3997
 5378±60 5281.0±128.8
R✶
(R⦿)
0.839+0.054-0.051
0.863+0.031-0.018
0.8577080+0.0531538-0.0456201
0.91729075+0.01947540-0.07050860
 0.86±0.08 0.86±0.05
log g
(log10(cm/s2))
4.538+0.090-0.159
4.54+0.02-0.04
4.5304300+0.0787213-0.0868912
 --- 4.59±0.07 4.53±0.08
Metallicity
(dex)
0.134+0.128-0.176
[Fe/H] 		0.14±0.04 [M/H] --- --- 0.16±0.04 [Fe/H] ---
v sin i
(km/s)
--- --- --- --- 2.7±1.5 ---
M✶
(M⦿)
0.9160+0.0780-0.0960
0.935+0.019-0.023
0.9100000+0.1436470-0.0805614
 --- 0.93±0.06 ---
Sp. T
G8 V --- --- --- K1 V ---
γ
(km/s)
---
0.6386+0.0023-0.0026
 --- 1.1716248298887546±0.5608252825168499 --- ---
Age
(Gyr)
---
2.8+3.8-1.7
 --- --- --- ---
ρ✶
(g/cm3)
---
2.064+0.137-1.410
2.0332374+0.4663734-0.4824426
 --- --- ---
L✶
(log10(L⦿))
--- ---
-0.2877621+0.0147430-0.0126335
-0.28653978+0.00591181-0.00599340
 --- ---
Print
Status
Confirmed Planet
Detected By
Transit
Tools
Transit Prediction Service
K2 Names
K2 Planets and Candidates
Transit
Source Lopez et al. 2019 Hardegree-Ullman et al. 2021 Christiansen et al. 2018
a/R✶
8.5+0.2-0.4
8.68+0.60-0.58
8.850+2.020-2.790
b
0.419+0.164-0.181
0.35+0.21-0.23
0.50+0.33-0.34
ω
(deg)
244+32-97
 --- ---
Mp
(M⨁)
3.10±1.05 --- ---
Mp
(MJup)
0.00975±0.00330 --- ---
e
0.0480+0.0540-0.0330
 --- <0.403
i
(deg)
87.2+1.2-1.0
87.72+1.52-1.54
86.9+2.2-4.6
P
(days)
2.35309±0.00022
2.35321+0.00037-0.00036
 2.35322±0.00036
ρ
(g/cm3)
4.9+2.0-1.7
 --- ---
Rp
(R⨁)
1.510+0.110-0.084
1.49+0.15-0.14
1.57+0.28-0.17
Rp
(RJup)
0.1347+0.0098-0.0075
0.133+0.013-0.012
0.140+0.025-0.015
Rp/R✶
0.01600+0.00083-0.00076
0.01628+0.00116-0.00111
0.0168+0.0029-0.0017
K
(m/s)
1.56±0.53 --- ---
a
(au)
0.03385+0.00023-0.00029
0.0338+0.0034-0.0031
 0.03380±0.00024
T14
(hours)
2.01±0.12
1.947+0.150-0.168
 1.73±0.23
TC
(days)
2457773.31683+0.00091-0.00090
2457740.3713+0.0061-0.0059
2457773.3170+0.0037-0.0038
S
(S⨁)
---
424.51+126.30-98.15
486+37-35
Teq
(K)
---
1157+78-74
 ---
Print
Status
Confirmed Planet
Detected By
Transit
Tools
Transit Prediction Service
K2 Names
K2 Planets and Candidates
Transit
Source Lopez et al. 2019 Hardegree-Ullman et al. 2021 Christiansen et al. 2018
a/R✶
11.1+0.2-0.5
11.39+0.53-0.70
10.8+1.3-3.0
b
0.369+0.130-0.136
0.28+0.17-0.18
 0.47±0.32
ω
(deg)
200+60-27
 --- ---
Mp
(M⨁)
6.31+1.13-1.23
 --- ---
Mp
(MJup)
0.0199+0.0036-0.0039
 --- ---
e
0.045+0.051-0.032
 --- <0.296
i
(deg)
88.1±0.7
88.59+0.92-0.97
87.5+1.8-3.3
P
(days)
3.56004+0.00012-0.00011
3.56015+0.00022-0.00023
3.55987+0.00023-0.00022
ρ
(g/cm3)
2.8+0.7-0.6
 --- ---
Rp
(R⨁)
2.299+0.120-0.087
2.26+0.18-0.17
2.52+0.34-0.16
Rp
(RJup)
0.2051+0.0107-0.0078
0.202+0.016-0.015
0.225+0.030-0.014
Rp/R✶
0.02439+0.00065-0.00059
0.02463+0.00091-0.00078
0.0267+0.0036-0.0015
K
(m/s)
2.78+0.50-0.55
 --- ---
a
(au)
0.04461+0.00030-0.00038
 0.0442±0.0039 0.04454±0.00032
T14
(hours)
2.38+0.05-0.06
2.339+0.089-0.087
2.329+0.095-0.088
TC
(days)
2457740.32182+0.00087-0.00089
2457740.3210+0.0029-0.0028
2457740.3223+0.0025-0.0027
S
(S⨁)
---
248.95+70.82-55.02
279+21-20
Teq
(K)
---
1012+65-61
 ---
Print
Status
Confirmed Planet
Detected By
Transit
Tools
Transit Prediction Service
K2 Names
K2 Planets and Candidates
Transit
Source Lopez et al. 2019 Hardegree-Ullman et al. 2021 Christiansen et al. 2018
a/R✶
14.7+0.3-0.7
14.81+0.64-0.86
12.8+1.6-3.6
b
0.241+0.159-0.152
0.23+0.17-0.16
0.47+0.31-0.32
ω
(deg)
83.0+82.0-38.0
 --- ---
Mp
(M⨁)
7.92+1.39-1.35
 --- ---
Mp
(MJup)
0.0249+0.0044-0.0042
 --- ---
e
0.043+0.041-0.030
 --- <0.348
i
(deg)
89.0±0.6
89.11+0.62-0.75
87.9+1.5-2.8
P
(days)
5.40479±0.00021
5.40484+0.00049-0.00051
5.40478+0.00048-0.00046
ρ
(g/cm3)
3.1+0.7-0.6
 --- ---
Rp
(R⨁)
2.390+0.104-0.084
2.46+0.19-0.18
2.66+0.39-0.18
Rp
(RJup)
0.2132+0.0093-0.0075
0.219+0.017-0.016
0.237+0.035-0.016
Rp/R✶
0.02532+0.00067-0.00063
0.02678+0.00093-0.00081
0.0283+0.0041-0.0017
K
(m/s)
3.03±0.52 --- ---
a
(au)
0.05893+0.00040-0.00050
0.0575+0.0050-0.0049
 0.05883±0.00042
T14
(hours)
2.70±0.07
2.764+0.097-0.086
2.97+0.13-0.11
TC
(days)
2457743.15989+0.00091-0.00093
2457743.1569+0.0037-0.0035
2457743.1607+0.0036-0.0037
S
(S⨁)
---
147.12+41.30-32.19
160+12-11
Teq
(K)
---
888+57-53
 ---
Print
Status
Confirmed Planet
Detected By
Transit
Tools
Transit Prediction Service
TOI
K2 Names
K2 Planets and Candidates
Transit
Source Lopez et al. 2019 Hardegree-Ullman et al. 2021 Christiansen et al. 2018 ExoFOP-TESS TOI Show Candidate Solutions >> << Hide Candidate Solutions
Teq
(K)
---
757+52-47
 --- 794
S
(S⨁)
---
77.79+23.51-17.73
91.1+7.0-6.6
 66.2634
P
(days)
8.26146+0.00021-0.00022
8.26147+0.00052-0.00053
8.26144+0.00045-0.00044
 8.2616616±0.0000190
Rp
(R⨁)
3.390+0.156-0.110
3.11+0.24-0.22
3.29+0.35-0.18
 3.309970±0.197543
Rp
(RJup)
0.3024+0.0139-0.0098
0.277+0.021-0.020
0.294+0.031-0.016
 0.2952963±0.0176236
δ
(%)
--- --- --- 0.13430000±0.00386387
T14
(hours)
2.97±0.05
2.967+0.076-0.070
3.063+0.107-0.085
 2.862±0.202
TC
(days)
2457740.64558+0.00085-0.00081
2457740.6451+0.0022-0.0021
2457740.6451+0.0020-0.0021
 2460219.144796±0.005467
a/R✶
19.5+0.4-0.9
20.40+1.20-1.57
19.4+1.9-4.9
 ---
b
0.468+0.096-0.126
0.38+0.15-0.21
0.44+0.31-0.30
 ---
ω
(deg)
180+40-44
 --- --- ---
Mp
(M⨁)
12.97+1.98-1.99
 --- --- ---
Mp
(MJup)
0.04081+0.00623-0.00626
 --- --- ---
e
0.0770+0.0480-0.0490
 --- <0.315 ---
i
(deg)
88.6±0.3
88.92+0.61-0.55
88.70+0.93-1.66
 ---
ρ
(g/cm3)
1.8+0.4-0.3
 --- --- ---
Rp/R✶
0.03599+0.00081-0.00073
0.03385+0.00110-0.00094
0.0349+0.0037-0.0015
 ---
K
(m/s)
4.31±0.67 --- --- ---
a
(au)
0.07820+0.00053-0.00066
0.0792+0.0076-0.0077
 0.07807±0.00056 ---
Print
Status
Confirmed Planet
Detected By
Transit
Tools
Transit Prediction Service
K2 Names
K2 Planets and Candidates
Transit
Source Lopez et al. 2019 Hardegree-Ullman et al. 2021 Christiansen et al. 2018
a/R✶
26.1+0.6-1.2
27.32+1.95-2.11
28.1+3.6-7.8
b
0.560+0.079-0.112
0.48+0.12-0.19
0.48+0.30-0.33
ω
(deg)
144+117-80
 --- ---
Mp
(M⨁)
1.63+2.12-1.18
 --- ---
Mp
(MJup)
0.00513+0.00667-0.00371
 --- ---
e
0.0620+0.0640-0.0430
 --- <0.364
i
(deg)
88.8±0.2
88.99+0.43-0.35
89.03+0.70-1.22
P
(days)
12.75758+0.00050-0.00048
12.75758+0.00120-0.00121
 12.75759±0.00092
ρ
(g/cm3)
0.4+0.5-0.3
 --- ---
Rp
(R⨁)
2.904+0.164-0.111
2.73+0.23-0.21
2.81+0.36-0.19
Rp
(RJup)
0.2591+0.0146-0.0099
0.244+0.021-0.019
0.251+0.032-0.017
Rp/R✶
0.03085+0.00088-0.00089
0.02982+0.00130-0.00122
0.0299+0.0039-0.0018
K
(m/s)
0.470+0.610-0.340
 --- ---
a
(au)
0.10447+0.00070-0.00088
0.1064+0.0108-0.0105
0.10430+0.00074-0.00075
T14
(hours)
3.20±0.08
3.243+0.130-0.111
3.19+0.14-0.12
TC
(days)
2457738.70235+0.00093-0.00092
2457738.7018+0.0044-0.0035
2457738.7019+0.0033-0.0035
S
(S⨁)
---
43.02+13.24-10.03
51.0+3.9-3.7
Teq
(K)
---
653+45-42
 ---
Print
Status
Confirmed Planet
Detected By
Radial Velocity, Transit
Tools
Transit Prediction Service
K2 Names
K2 Planets and Candidates
Transit
Source Lopez et al. 2019 Hardegree-Ullman et al. 2021
a/R✶
57.7+1.2-2.6
58.59+4.84-4.64
b
0.558+0.284-0.356
0.73+0.05-0.07
ω
(deg)
164+92-72
 ---
Mp
(M⨁)
4.32+5.26-3.03
 ---
Mp
(MJup)
0.0136+0.0165-0.0095
 ---
e
0.0590+0.0630-0.0400
 ---
i
(deg)
89.4+0.4-0.3
 89.29±0.11
P
(days)
41.96797+0.00843-0.00725
41.96645+0.00603-0.00665
ρ
(g/cm3)
0.90+1.10-0.60
 ---
Rp
(R⨁)
3.013+0.303-0.251
3.18+0.28-0.26
Rp
(RJup)
0.2688+0.0270-0.0224
0.284+0.025-0.023
Rp/R✶
0.03187+0.00295-0.00250
0.03472+0.00171-0.00177
K
(m/s)
0.830+1.020-0.580
 ---
a
(au)
0.23109+0.00154-0.00196
0.2287+0.0249-0.0231
T14
(hours)
4.75+0.80-1.42
4.035+0.156-0.172
TC
(days)
2457773.86156+0.01863-0.03219
 2457773.8541±0.0044
Teq
(K)
---
445+31-30
S
(S⨁)
---
9.290+2.920-2.230
Print
Known Objects
6 Confirmed Planets
1 K2 Targets
2 2MASS Point Source Catalog
Data Files
1 K2 Time Series
6 Associated Literature Data
System
Star
Confirmed
Candidate
False Positive Planet
Controversial
False Positive
Aliases
Data Access
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Time Series
Kepler | K2
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