TOI-521 Overview

TOI-521 0.42 R_⦿ 3439.00 K

TOI-521 b

0.177 R_Jup

Overview Parameters Nearby Data Bibliography 3 Legend Expand All

TOI-521 Architecture & Discovery Information

Name	Orbital Separation	Planet Size	Method	Year	Reference	Disposition
TOI-521
TOI-521 b	1.54 d	1.98 R_⨁	Transit	2025	Lacedelli et al. 2026	Confirmed Planet

TOI-521 Stellar Parameters (3 Solutions)

RA: 08h13m22.62s

Dec: +12d13m19.59s

Distance: 60.9425+0.2247-0.2230
pc

Parallax: 16.3803000±0.0598232 mas

Ecliptic Latitude: -7.50031 deg

Ecliptic Longitude: 122.8055 deg

Galactic Latitude: 23.63646 deg

Galactic Longitude: 210.90176 deg

Total Proper Motion: 121.183281±0.076399 mas/yr

Proper Motion (RA): 90.4089000±0.0922865 mas/yr

Proper Motion (Dec): 80.6946000±0.0497256 mas/yr

Photometry: m_V
14.691±0.066; m_TESS
12.4029000±0.0072835; m_J
10.921±0.022; m_H
10.357±0.020; m_Ks
10.089±0.019; m_W1
9.9850±0.0230; m_W2
9.854±0.021; m_W3
9.727±0.047; m_W4
9.006; m_Gaia
13.586100±0.000364; m_B
16.268±0.147

Tools: Planetary Systems; ExoFOP Target Overview Page; IRSA Finding Chart; TOI; Stellar Hosts

Source	Lacedelli et al. 2026	TICv8	ExoFOP
T_eff (K)	3544±100	3465.0±157.0	3439±69
R_✶ (R_⦿)	0.421±0.028	0.4200280±0.0125005	0.420028001070023±0.012500500000000
log g (log₁₀(cm/s²))	4.97±0.10	4.8084000±0.0045697	4.974860±0.436074
L_✶ (log₁₀(L_⦿))	-1.60+0.01-0.01	-1.63994+0.09413-0.12035	---
ρ_✶ (g/cm³)	8.2+0.6-0.7	7.874458±0.317405	---
M_✶ (M_⦿)	0.420±0.030	0.4138950±0.0202719	---
Metallicity (dex)	-0.12±0.08 [Fe/H]	---	---
γ (km/s)	-9.310±1.100	---	---
Age (Gyr)	>0.8	---	---
CAII LOG RHK	-5.500±0.036	---	---
Sp. T	M3	---	---

TOI-521 b Planetary Parameters (2 Solutions)

Status: Confirmed Planet

Detected By: Radial Velocity, Transit

Tools: Planetary Systems; Transit Prediction Service; TOI; Transit

Source	Lacedelli et al. 2026	ExoFOP
T_eq (K)	794±35	709.887341401445
S (S_⨁)	66±12	60.0176144930838
P (days)	1.54285047+0.00000100-0.00000080	1.54284863301638±0.00000413439740
R_p (R_⨁)	1.98±0.14	1.96530323770976±1.11616640000000
R_p (R_Jup)	0.177±0.012	0.175332912983761±0.099577867950116
δ (%)	---	0.215448557809037±0.013757423000000
T₁₄ (hours)	1.18±0.01	1.19588980986732±0.32045240000000
T_C (days)	2458492.7153±0.0005 (BJD)	2458492.71641100±0.00060947 (BJD)
a/R_✶	10.1+0.2-0.3	---
b	0.24+0.11-0.14	---
ω (deg)	90	---
M_p (M_⨁)	5.3±1.0	---
M_p (M_Jup)	0.017±0.003	---
e	0	---
i (deg)	88.6+0.8-0.7	---
ρ (g/cm³)	3.8±1.1	---
R_p/R_✶	0.0431±0.0009	---
K (m/s)	5.26+0.95-0.98	---
a (au)	0.0195±0.0003	---

Nearby Data (within 30 arcseconds) Browse Nearby Data

Known Objects: 1 Confirmed Planets; 1 2MASS Point Source Catalog

Data Files: 1 Associated Literature Data

Bibliography (3 References)

Sibling sub-Neptunes around sibling M dwarfs: TOI-521 and TOI-912
Lacedelli et al. 2026 Reference Overview
The Revised TESS Input Catalog and Candidate Target List
TICv8 Reference Overview
ExoFOP TOI Table
ExoFOP

Legend

System
Star
Confirmed
Candidate
False Positive Planet
Controversial
False Positive

Aliases
Data Access
Transit Prediction Service
Time Series
Kepler | K2

External Link
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Debug Info

https://vmexoweb2.ipac.caltech.edu/data/Overviews_2.0/39/TOI-521.json

TOI-521

Catalog Parameters

08h13m22.62s

Dec

dec

+12d13m19.59s

elat

-7.50031

elon

122.8055

glat

23.63646

glon

210.90176

m_V

sy_vmag

14.691±0.066

m_TESS

sy_tmag

12.4029000±0.0072835

m_J

sy_jmag

10.921±0.022

m_H

sy_hmag

10.357±0.020

m_Ks

sy_kmag

10.089±0.019

sy_kepmag

no_data

m_W1

sy_w1mag

9.9850±0.0230

m_W2

sy_w2mag

9.854±0.021

m_W3

sy_w3mag

9.727±0.047

m_W4

sy_w4mag

9.006

sy_icmag

no_data

m_Gaia

sy_gaiamag

13.586100±0.000364

m_B

sy_bmag

16.268±0.147

sy_gmag

no_data

sy_imag

no_data

sy_rmag

no_data

sy_umag

no_data

sy_zmag

no_data

sy_pm

121.183281±0.076399

μ_δ

sy_pmdec

80.6946000±0.0497256

μ_α

sy_pmra

90.4089000±0.0922865

sy_plx

16.3803000±0.0598232

Distance

sy_dist

60.9425+0.2247-0.2230

Set Parameters

R_✶

st_rad

0.420028001070023±0.012500500000000

T_eff

st_teff

3439±69