Skip to main content

Research Repository

Advanced Search

Hidden depths in the local Universe: The Stellar Stream Legacy Survey

Martínez-Delgado, David; Cooper, Andrew P.; Román, Javier; Pillepich, Annalisa; Erkal, Denis; Pearson, Sarah; Moustakas, John; Laporte, Chervin F.P.; Laine, Seppo; Akhlaghi, Mohammad; Lang, Dustin; Makarov, Dmitry; Borlaff, Alejandro S.; Donatiello, Giuseppe; Pearson, William J.; Miró-Carretero, Juan; Cuillandre, Jean-Charles; Domínguez, Helena; Roca-Fàbrega, Santi; Frenk, Carlos S.; Schmidt, Judy; Gómez-Flechoso, María A.; Guzman, Rafael; Libeskind, Noam I.; Dey, Arjun; Weaver, Benjamin A.; Schlegel, David; Myers, Adam D.; Valdes, Frank G.

Hidden depths in the local Universe: The Stellar Stream Legacy Survey Thumbnail


David Martínez-Delgado

Andrew P. Cooper

Javier Román

Annalisa Pillepich

Denis Erkal

Sarah Pearson

John Moustakas

Chervin F.P. Laporte

Seppo Laine

Mohammad Akhlaghi

Dustin Lang

Dmitry Makarov

Alejandro S. Borlaff

Giuseppe Donatiello

William J. Pearson

Juan Miró-Carretero

Jean-Charles Cuillandre

Helena Domínguez

Santi Roca-Fàbrega

Judy Schmidt

María A. Gómez-Flechoso

Rafael Guzman

Noam I. Libeskind

Arjun Dey

Benjamin A. Weaver

David Schlegel

Adam D. Myers

Frank G. Valdes


Context. Mergers and tidal interactions between massive galaxies and their dwarf satellites are a fundamental prediction of the Lambda-cold dark matter cosmology. These events are thought to provide important observational diagnostics of non-linear structure formation. Stellar streams in the Milky Way and Andromeda are spectacular evidence for ongoing satellite disruption. However, constructing a statistically meaningful sample of tidal streams beyond the Local Group has proven a daunting observational challenge, and the full potential for deepening our understanding of galaxy assembly using stellar streams has yet to be realised. Aims. Here we introduce the Stellar Stream Legacy Survey, a systematic imaging survey of tidal features associated with dwarf galaxy accretion around a sample of ∼3100 nearby galaxies within z ∼ 0.02, including about 940 Milky Way analogues. Methods. Our survey exploits public deep imaging data from the DESI Legacy Imaging Surveys, which reach surface brightness as faint as ∼29 mag arcsec−2 in the r band. As a proof of concept of our survey, we report the detection and broad-band photometry of 24 new stellar streams in the local Universe. Results. We discuss how these observations can yield new constraints on galaxy formation theory through comparison to mock observations from cosmological galaxy simulations. These tests will probe the present-day mass assembly rate of galaxies, the stellar populations and orbits of satellites, the growth of stellar halos, and the resilience of stellar disks to satellite bombardment.


Martínez-Delgado, D., Cooper, A. P., Román, J., Pillepich, A., Erkal, D., Pearson, S., …Valdes, F. G. (2023). Hidden depths in the local Universe: The Stellar Stream Legacy Survey. Astronomy & Astrophysics, 671, Article A141.

Journal Article Type Article
Acceptance Date Nov 29, 2022
Online Publication Date Mar 16, 2023
Publication Date 2023
Deposit Date Jul 5, 2023
Publicly Available Date Jul 5, 2023
Journal Astronomy & Astrophysics
Print ISSN 0004-6361
Electronic ISSN 1432-0746
Publisher EDP Sciences
Peer Reviewed Peer Reviewed
Volume 671
Article Number A141


You might also like

Downloadable Citations