NIRPS tightens the mass estimate of GJ 3090 b and detects a planet near the stellar rotation period
Lamontagne, P. ; Hoeijmakers, H.J. LU
and Zins, G.
(2026)
In Astronomy and Astrophysics
706.
- Abstract
- We present an updated characterization of the planetary system orbiting the nearby M2 dwarf GJ 3090 (TOI-177; d=22 pc), based on new high-precision radial velocity (RV) observations from NIRPS and HARPS. With an orbital period of 2.85 d, the transiting sub-Neptune GJ 3090 b has a mass we refine to 4.52 ± 0.47 M>, which, combined with our derived radius of 2.18 ± 0.06 R2, yields a density of 2.40-0.30+0.33 gcm-3. The combined interior structure and atmospheric constraints indicate that GJ 3090 b is a compelling water-world candidate, with a volatile-rich envelope in which water likely represents a significant fraction. We also confirm the presence of a second planet, GJ 3090 c, a sub-Neptune with a 15.9 d orbit and a minimum mass of 10.0... (More)
- We present an updated characterization of the planetary system orbiting the nearby M2 dwarf GJ 3090 (TOI-177; d=22 pc), based on new high-precision radial velocity (RV) observations from NIRPS and HARPS. With an orbital period of 2.85 d, the transiting sub-Neptune GJ 3090 b has a mass we refine to 4.52 ± 0.47 M>, which, combined with our derived radius of 2.18 ± 0.06 R2, yields a density of 2.40-0.30+0.33 gcm-3. The combined interior structure and atmospheric constraints indicate that GJ 3090 b is a compelling water-world candidate, with a volatile-rich envelope in which water likely represents a significant fraction. We also confirm the presence of a second planet, GJ 3090 c, a sub-Neptune with a 15.9 d orbit and a minimum mass of 10.0 ± 1.3 M⊕, which does not transit. Despite its proximity to the star s 18 d rotation period, our joint analysis using a multidimensional Gaussian process (GP) model that incorporates TESS photometry and differential stellar temperature measurements distinguishes this planetary signal from activity-induced variability. In addition, we place new constraints on a non-transiting planet candidate with a period of 12.7 d, suggested in earlier RV analyses. This candidate remains a compelling target for future monitoring. These results highlight the crucial role of multidimensional GP modelling in disentangling planetary signals from stellar activity, enabling the detection of a planet near the stellar rotation period that could have remained undetected with traditional approaches. © The Authors 2026. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/61d034fd-70a3-444d-9be4-a3b7dd68dcae
- author
- Lamontagne, P.
; Hoeijmakers, H.J.
LU
and Zins, G.
- author collaboration
- organization
- publishing date
- 2026
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Instrumentation: spectrographs, Planet-star interactions, Planets and satellites: detection, Planets and satellites: dynamical evolution and stability, Planets and satellites: fundamental parameters, Astrophysics, Orbits, Planets, Rotation, Satellites, Stars, Gaussian process models, Instrumentation:spectrographs, Neptune, Planets and satellites: detections, Planets and satellites: dynamical evolution and stabilities, Rotation period, Stellar rotation, Stellars, Temperature measurement
- in
- Astronomy and Astrophysics
- volume
- 706
- article number
- A278
- publisher
- EDP Sciences
- external identifiers
-
- scopus:105031404038
- ISSN
- 0004-6361
- DOI
- 10.1051/0004-6361/202556887
- language
- English
- LU publication?
- yes
- id
- 61d034fd-70a3-444d-9be4-a3b7dd68dcae
- date added to LUP
- 2026-04-07 09:30:32
- date last changed
- 2026-04-07 09:31:32
@article{61d034fd-70a3-444d-9be4-a3b7dd68dcae,
abstract = {{We present an updated characterization of the planetary system orbiting the nearby M2 dwarf GJ 3090 (TOI-177; d=22 pc), based on new high-precision radial velocity (RV) observations from NIRPS and HARPS. With an orbital period of 2.85 d, the transiting sub-Neptune GJ 3090 b has a mass we refine to 4.52 ± 0.47 M>, which, combined with our derived radius of 2.18 ± 0.06 R2, yields a density of 2.40-0.30+0.33 gcm-3. The combined interior structure and atmospheric constraints indicate that GJ 3090 b is a compelling water-world candidate, with a volatile-rich envelope in which water likely represents a significant fraction. We also confirm the presence of a second planet, GJ 3090 c, a sub-Neptune with a 15.9 d orbit and a minimum mass of 10.0 ± 1.3 M⊕, which does not transit. Despite its proximity to the star s 18 d rotation period, our joint analysis using a multidimensional Gaussian process (GP) model that incorporates TESS photometry and differential stellar temperature measurements distinguishes this planetary signal from activity-induced variability. In addition, we place new constraints on a non-transiting planet candidate with a period of 12.7 d, suggested in earlier RV analyses. This candidate remains a compelling target for future monitoring. These results highlight the crucial role of multidimensional GP modelling in disentangling planetary signals from stellar activity, enabling the detection of a planet near the stellar rotation period that could have remained undetected with traditional approaches. © The Authors 2026.}},
author = {{Lamontagne, P. and Hoeijmakers, H.J. and Zins, G.}},
issn = {{0004-6361}},
keywords = {{Instrumentation: spectrographs; Planet-star interactions; Planets and satellites: detection; Planets and satellites: dynamical evolution and stability; Planets and satellites: fundamental parameters; Astrophysics; Orbits; Planets; Rotation; Satellites; Stars; Gaussian process models; Instrumentation:spectrographs; Neptune; Planets and satellites: detections; Planets and satellites: dynamical evolution and stabilities; Rotation period; Stellar rotation; Stellars; Temperature measurement}},
language = {{eng}},
publisher = {{EDP Sciences}},
series = {{Astronomy and Astrophysics}},
title = {{NIRPS tightens the mass estimate of GJ 3090 b and detects a planet near the stellar rotation period}},
url = {{http://dx.doi.org/10.1051/0004-6361/202556887}},
doi = {{10.1051/0004-6361/202556887}},
volume = {{706}},
year = {{2026}},
}