Registry · exoplanet

AU Mic c

Exoplanet

harvesting The full record is being pulled from the archives right now — measurement tables, the Gaia row, catalogue photometry. This page will fill itself in.

Right ascension: 20h 45m 09.87s
Declination: −31° 20′ 32.8″
Galactic l, b: 12.653, -36.8
Magnitude V: 8.81
Distance: 9.7221 pc

Planet

NASA Exoplanet Archive, composite parameters

Host star	AU Mic · M1 V
Discovery	Transit, 2021 · Transiting Exoplanet Survey Satellite (TESS)
Orbital period	18.859 d
Semi-major axis	0.119 au
Eccentricity	0.18
Radius	2.79 R⊕ · 0.2489 R♃
Mass	14.46 M⊕ · 0.0455 M♃
Density	3.9 g/cm³
Equilibrium temperature	424.7 K
System distance	9.7221 pc

Published measurements

6 quantities measured more than once

One object can carry a dozen published estimates of the same quantity. The register keeps them side by side rather than picking a winner — the citation is part of the value.

Mass 6 values

Value	Unit	Uncertainty	Band / method	Source	Reference	Year
11.6	M_earth	± 3.3	Transit	NASA Exoplanet Archive	Donati et al. 2025	2025
14.46	M_earth	± 3.24	Transit	NASA Exoplanet Archive	Mallorquín et al. 2024	2024
14.2	M_earth	± 4.8	Transit	NASA Exoplanet Archive	Donati et al. 2023	2023
22.2	M_earth	± 6.7	Transit	NASA Exoplanet Archive	Zicher et al. 2022	2022
13.6	M_earth	± 11.4	Transit	NASA Exoplanet Archive	Martioli et al. 2021	2021
9.6	M_earth	± 2.07	Transit	NASA Exoplanet Archive	Cale et al. 2021	2021

Radius 5 values

Value	Unit	Uncertainty	Band / method	Source	Reference	Year
2.79	R_earth	± 0.18	Transit	NASA Exoplanet Archive	Mallorquín et al. 2024	2024
2.522021	R_earth	± 0.2466	Transit	NASA Exoplanet Archive	Wittrock et al. 2023	2023
2.56	R_earth	± 0.12	Transit	NASA Exoplanet Archive	Szabó et al. 2022	2022
2.79	R_earth	± 0.31	Transit	NASA Exoplanet Archive	Gilbert et al. 2022	2022
3.24	R_earth	± 0.16	Transit	NASA Exoplanet Archive	Martioli et al. 2021	2021

Orbital period 8 values

Value	Unit	Uncertainty	Band / method	Source	Reference	Year
18.85902	d		Transit	NASA Exoplanet Archive	Donati et al. 2025	2025
18.85902	d	± 2.20e-05	Transit	NASA Exoplanet Archive	Mallorquín et al. 2024	2024
18.85882	d		Transit	NASA Exoplanet Archive	Donati et al. 2023	2023
18.85969	d	± 8.00e-05	Transit	NASA Exoplanet Archive	Wittrock et al. 2023	2023
18.85902	d	± 1.60e-06	Transit	NASA Exoplanet Archive	Zicher et al. 2022	2022
18.85898	d	± 5.30e-05	Transit	NASA Exoplanet Archive	Gilbert et al. 2022	2022
18.85902	d	± 1.60e-05	Transit	NASA Exoplanet Archive	Martioli et al. 2021	2021
18.85899	d		Transit	NASA Exoplanet Archive	Cale et al. 2021	2021

Semi-major axis 6 values

Value	Unit	Uncertainty	Band / method	Source	Reference	Year
0.119	au	± 0.011	Transit	NASA Exoplanet Archive	Mallorquín et al. 2024	2024
0.1108	au	± 0.002	Transit	NASA Exoplanet Archive	Wittrock et al. 2023	2023
0.0993	au	± 0.0085	Transit	NASA Exoplanet Archive	Szabó et al. 2022	2022
0.11	au	± 0.01	Transit	NASA Exoplanet Archive	Gilbert et al. 2022	2022
0.1101	au	± 0.0022	Transit	NASA Exoplanet Archive	Martioli et al. 2021	2021
0.1101	au	± 0.002	Transit	NASA Exoplanet Archive	Cale et al. 2021	2021

Eccentricity 5 values

Value	Uncertainty	Band / method	Source	Reference	Year
0.18	± 0.08	Transit	NASA Exoplanet Archive	Mallorquín et al. 2024	2024
0.00338	± 0.00164	Transit	NASA Exoplanet Archive	Wittrock et al. 2023	2023
0.041	± 0.047	Transit	NASA Exoplanet Archive	Zicher et al. 2022	2022
0.13	± 0.16	Transit	NASA Exoplanet Archive	Gilbert et al. 2022	2022
0		Transit	NASA Exoplanet Archive	Martioli et al. 2021	2021

Equilibrium temperature 3 values

Value	Unit	Uncertainty	Band / method	Source	Reference	Year
424.7	K	± 24.2	Transit	NASA Exoplanet Archive	Mallorquín et al. 2024	2024
459	K	± 13	Transit	NASA Exoplanet Archive	Wittrock et al. 2023	2023
454	K	± 16	Transit	NASA Exoplanet Archive	Martioli et al. 2021	2021

In the same field

within 9 arcmin · wider search

Object	Type	Separation	V
AU Mic d	Exoplanet	0″	8.81
AU Mic e	Exoplanet	0″	8.81
AU Mic	Star	0″	—
AU Mic b	Exoplanet	0″	8.81
HD 197481c	Planet	7.083″	—
HD 197481b	Planet	7.083″	—
HD 197481d	Planet Candidate	7.083″	—
HD 197481	BYDraV*	7.083″	8.627
UCAC4 294-224020	HighPM*	433.3″	13.02

Provenance

where this card came from

Archive	Read at (UTC)	Record
Seeded from the bulk archive load; no per-object fetch yet.

Machine-readable: /api/v1/object/au-mic-c · Registry entry updated 2026-08-14.