Direct Imaging Discovery of Giant Exoplanet β Pictoris d: A Decade-long Game of Hide-and-seek
Abstract
We report the direct imaging discovery of a third exoplanet in the β Pictoris ( β Pic) system. We detect β Pictoris d ( β Pic d) in noncoronagraphic observations obtained with the Very Large Telescope (VLT) Enhanced Resolution Imager and Spectrograph (ERIS), as well as multi-epoch archival datasets from the JWST Near Infrared Camera (NIRCam) and VLT/SPHERE. Astrometric measurements over an 11 yr baseline demonstrate that it is consistent with a gravitationally bound source with orbital motion. Joint multi-planet orbit fits of all three planets in the system yield a semimajor axis of 26 . 0 − 6.1 + 2.2 au and inclination 89 . 0 − 0.6 + 0.7 deg for planet d. β Pic d has a larger orbital semimajor axis than the other known planets in the system, but is coplanar with the inner two planets, and its orbit is consistent with sculpting the inner edge of the debris disk. β Pic d has a contrast of Δ L ′ = 12.11 ± 0.15 mag, with colors and luminosity that closely match those of 51 Eri b, another exoplanet in the β Pic moving group. Its VLT/ERIS and JWST/NIRCam colors are distinct from those of free-floating planetary-mass objects of a similar age and temperature. Its red F410M − F444W color indicates strong CO 2 absorption in its atmosphere and suggests significant enhancement in metals compared to free-floating objects. From the ATMO hot-start evolutionary models, we estimate an effective temperature of 60 0 − 60 + 45 K and mass of 2.4 ± 0.6 M Jup , which also closely matches similar estimates for 51 Eri b. β Pic d is among the lowest-mass exoplanets imaged from the ground. This discovery highlights the deep sensitivity achievable with ground-based imaging in the mid-infrared and the discovery potential of future high-contrast observations with the Extremely Large Telescope.
Related
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- The JWST Sub-Jupiters Survey: Direct Imaging Discovery of a Giant Planet and a Debris Disk Around the Young M-dwarf RX J0534.0-0221
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- Astrometric planet search around southern ultracool dwarfs. V. Discovery of the exoplanet candidate PALTA-1 b
- Deep HST/STIS Coronagraphic Imaging of the β Pictoris Debris Disk: On the Scattered Light Component of the Cat's Tail
BibTeX
@article{sutlieff2026direct,
title = {{Direct Imaging Discovery of Giant Exoplanet β Pictoris d: A Decade-long Game of Hide-and-seek}},
author = {Ben Sutlieff and Markus Bonse and Valentin Christiaens and Clémence Fontanive and Elisabeth Matthews and Luke Parker and Tim Pearce and Jayne Birkby and Beth Biller and Trent Dupuy and Emily Garvin and Leyla Iskandarli and Jens Kammerer and Yifan Zhou and Robert de Rosa and Aarynn Carter and Sasha Hinkley and Matthew Kenworthy and William Balmer and Iain Hammond and James Mang and Caroline Morley and Mark Neeser and Olivier Absil and Anthony Boccaletti and Mariangela Bonavita and Brendan Bowler and Xueqing Chen and Felix Dannert and Julien Girard and Markus Kasper and Anne-Marie Lagrange and Pengyu Liu and Gilles Orban de Xivry and Michael Poon and Sascha Quanz and Benoît Serra and Johanna Vos and Kevin Wagner and Jason Wang and Bernhard Schölkopf and Guido Agapito and Alex Agudo Berbel and Dániel Apai and Andrea Baruffolo and Martin Black and Marco Bonaglia and Runa Briguglio and Yixian Cao and Luca Carbonaro and Lee Chapman and Giovanni Cresci and Yigit Dallilar and Richard Davies and Matthias Deysenroth and Ivan Di Antonio and Amico Di Cianno and Gianluca Di Rico and David Doelman and Mauro Dolci},
journal = {The Astrophysical Journal Letters},
year = {2026},
month = jul,
doi = {10.3847/2041-8213/ae80a0},
eprint = {2606.23801},
archivePrefix = {arXiv},
url = {https://hal.science/hal-05845908v1},
note = {CC BY},
}
RIS
TY - JOUR
TI - Direct Imaging Discovery of Giant Exoplanet β Pictoris d: A Decade-long Game of Hide-and-seek
AU - Ben Sutlieff
AU - Markus Bonse
AU - Valentin Christiaens
AU - Clémence Fontanive
AU - Elisabeth Matthews
AU - Luke Parker
AU - Tim Pearce
AU - Jayne Birkby
AU - Beth Biller
AU - Trent Dupuy
AU - Emily Garvin
AU - Leyla Iskandarli
AU - Jens Kammerer
AU - Yifan Zhou
AU - Robert de Rosa
AU - Aarynn Carter
AU - Sasha Hinkley
AU - Matthew Kenworthy
AU - William Balmer
AU - Iain Hammond
AU - James Mang
AU - Caroline Morley
AU - Mark Neeser
AU - Olivier Absil
AU - Anthony Boccaletti
AU - Mariangela Bonavita
AU - Brendan Bowler
AU - Xueqing Chen
AU - Felix Dannert
AU - Julien Girard
AU - Markus Kasper
AU - Anne-Marie Lagrange
AU - Pengyu Liu
AU - Gilles Orban de Xivry
AU - Michael Poon
AU - Sascha Quanz
AU - Benoît Serra
AU - Johanna Vos
AU - Kevin Wagner
AU - Jason Wang
AU - Bernhard Schölkopf
AU - Guido Agapito
AU - Alex Agudo Berbel
AU - Dániel Apai
AU - Andrea Baruffolo
AU - Martin Black
AU - Marco Bonaglia
AU - Runa Briguglio
AU - Yixian Cao
AU - Luca Carbonaro
AU - Lee Chapman
AU - Giovanni Cresci
AU - Yigit Dallilar
AU - Richard Davies
AU - Matthias Deysenroth
AU - Ivan Di Antonio
AU - Amico Di Cianno
AU - Gianluca Di Rico
AU - David Doelman
AU - Mauro Dolci
PY - 2026
DA - 2026/07/15
JO - The Astrophysical Journal Letters
DO - 10.3847/2041-8213/ae80a0
UR - https://hal.science/hal-05845908v1
AB - We report the direct imaging discovery of a third exoplanet in the β Pictoris ( β Pic) system. We detect β Pictoris d ( β Pic d) in noncoronagraphic observations obtained with the Very Large Telescope (VLT) Enhanced Resolution Imager and Spectrograph (ERIS), as well as multi-epoch archival datasets from the JWST Near Infrared Camera (NIRCam) and VLT/SPHERE. Astrometric measurements over an 11 yr baseline demonstrate that it is consistent with a gravitationally bound source with orbital motion. Joint multi-planet orbit fits of all three planets in the system yield a semimajor axis of 26 . 0 − 6.1 + 2.2 au and inclination 89 . 0 − 0.6 + 0.7 deg for planet d. β Pic d has a larger orbital semimajor axis than the other known planets in the system, but is coplanar with the inner two planets, and its orbit is consistent with sculpting the inner edge of the debris disk. β Pic d has a contrast of Δ L ′ = 12.11 ± 0.15 mag, with colors and luminosity that closely match those of 51 Eri b, another exoplanet in the β Pic moving group. Its VLT/ERIS and JWST/NIRCam colors are distinct from those of free-floating planetary-mass objects of a similar age and temperature. Its red F410M − F444W color indicates strong CO 2 absorption in its atmosphere and suggests significant enhancement in metals compared to free-floating objects. From the ATMO hot-start evolutionary models, we estimate an effective temperature of 60 0 − 60 + 45 K and mass of 2.4 ± 0.6 M Jup , which also closely matches similar estimates for 51 Eri b. β Pic d is among the lowest-mass exoplanets imaged from the ground. This discovery highlights the deep sensitivity achievable with ground-based imaging in the mid-infrared and the discovery potential of future high-contrast observations with the Extremely Large Telescope.
SN - 2041-8205
SN - 2041-8213
ER -