VENUS: When red meets blue A multiply imaged little red dot with an apparent blue companion behind the galaxy cluster Abell 383
Journal article, 2026
We report the discovery of a doubly imaged little red dot (LRD) candidate behind the galaxy cluster Abell 383, which we dub A383-LRD1. Initially classified as a dropout galaxy in HST imaging with several ground-based emission line detections placing it at z(spec) = 6.027, new JWST/NIRCam observations taken as part of the cycle 4 VENUS survey now reveal that the source consists of two underlying components. These consist of a red point-source with a V-shaped SED consistent with LRD selection criteria and a nearby (similar to 380 pc) compact blue companion, which was the main contributor to the previous rest-frame UV detections. Based on lensing symmetry and its SED, the LRD appears to lie at a similar redshift as well. The magnification of the two images of A383-LRD1 is mu(A) = 16.2 +/- 1.2 and mu(B) = 9.0 +/- 0.6, respectively, and the predicted time delay between them is Delta t(grav) = 5.20 +/- 0.14 yr (similar to 0.7 yr in the rest-frame). After correcting for the lensing magnification, we derived an absolute magnitude of M-UV,M- LRD = -16.8 +/- 0.3 for the LRD and M-UV,M- BC = -18.2 +/- 0.2 for the blue companion. We performed SED fits to both components, revealing the LRD to show the best fit with a black hole star (BH*) model and a substantial host galaxy, along with the blue companion with an extremely young, emission-line dominated star-forming nebula. If it is verified spectroscopically in the future, A383-LRD1 would represent the second known multiply imaged LRD detected to date, following A2744-QSO1. To our knowledge, it would also stand as the first LRD system with a confirmed detection of [C II]lambda 158 mu m emission from ALMA observations. Thanks to the lensing magnification, this system opens a unique door to studying the relation between a LRD, its host galaxy, and its environment. It represents a prime candidate for deep JWST spectroscopy and high-resolution ALMA follow-up observations.
galaxies: high-redshift
quasars: general
gravitational lensing: strong
Author
Miriam Golubchik
Ben-Gurion University of the Negev
Lukas J. Furtak
University of Texas at Austin
University of Texas
Joseph F. V. Allingham
Ben-Gurion University of the Negev
Adi Zitrin
Ben-Gurion University of the Negev
Hollis B. Akins
University of Texas at Austin
University of Texas
Vasily Kokorev
University of Texas
University of Texas at Austin
Seiji Fujimoto
University of Toronto
Abdurro'uf
Indiana University
Ricardo O. Amorin
Spanish National Research Council (CSIC)
Franz E. Bauer
Universidad de Tarapacá
Rachel Bezanson
University of Pittsburgh
Marusa Bradac
University of California
University of Ljubljana
Larry D. Bradley
Space Telescope Science Institute (STScI)
Gabriel B. Brammer
University of Copenhagen
John Chisholm
University of Texas at Austin
University of Texas
Dan Coe
Association of Universities for Research in Astronomy (AURA)
Space Telescope Science Institute (STScI)
Johns Hopkins University
Christopher J. Conselice
University of Manchester
Pratika Dayal
University of Toronto
Miroslava Dessauges-Zavadsky
University of Geneva
Jose M. Diego
Instituto de Física de Cantabria
Andreas L. Faisst
California Institute of Technology (Caltech)
Qinyue Fei
University of Toronto
Henry C. Ferguson
Space Telescope Science Institute (STScI)
Steven L. Finkelstein
University of Texas at Austin
University of Texas
Brenda L. Frye
University of Arizona
Mauro Gonzalez-Otero
Spanish National Research Council (CSIC)
Jenny E. Greene
Princeton University
Yuichi Harikane
University of Tokyo
Tiger Yu-Yang Hsiao
University of Texas at Austin
University of Texas
Kohei Inayoshi
Beijing University of Technology
Yolanda Jimenez-Teja
Spanish National Research Council (CSIC)
Bairro Imperial Sao Cristovao
Kirsten Knudsen
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Anton M. Koekemoer
Space Telescope Science Institute (STScI)
Ivo Labbe
Swinburne University of Technology
Ray A. Lucas
Space Telescope Science Institute (STScI)
Georgios E. Magdis
University of Copenhagen
Jorryt Matthee
Institute of Science and Technology Austria
Matteo Messa
Istituto nazionale di astrofisica (INAF)
Rohan P. Naidu
Massachusetts Institute of Technology (MIT)
Minami Nakane
University of Tokyo
Gael Noirot
Space Telescope Science Institute (STScI)
Richard Pan
Tufts University
Casey Papovich
Texas A&M University
Johan Richard
Université de Lyon
Massimo Ricotti
University of Maryland
Luke Robbins
Tufts University
Daniel P. Stark
University of California
Fengwu Sun
Harvard-Smithsonian Center for Astrophysics
Tommaso Treu
University of California
Roberta Tripodi
Istituto nazionale di astrofisica (INAF)
Eros Vanzella
Istituto nazionale di astrofisica (INAF)
Chris Willott
National Research Council Canada
Rogier A. Windhorst
Arizona State University
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 710 A226Subject Categories (SSIF 2025)
Computer Sciences
Astronomy, Astrophysics, and Cosmology
DOI
10.1051/0004-6361/202558407