6 papers
Discovery of an extremely narrow trail-like feature crossing the Veil Supernova Remnant in deep amateur observations
David Martinez-Delgado, Jan-Niklas Pippert, Miguel A. Perez-Torres +9
We report the discovery of an extremely narrow and highly collimated gaseous trail-like structure crossing the eastern region of the Veil Nebula (Cygnus Loop). The feature was firs…
A stellar stream around the spiral galaxy Messier 61 in Rubin First Look imaging
Aaron J. Romanowsky, David MartÃnez-Delgado, Giuseppe Donatiello +2
We present the first stellar stream discovered with the Vera C. Rubin Observatory, around spiral galaxy M61 (NGC 4303) in Virgo First Look imaging. The stream is narrow, radially-o…
Tracing satellite planes in the Sculptor group: II. Discovery of five faint dwarf galaxies in the DESI Legacy Survey
David Martinez-Delgado, Michael Stein, Marcel S. Pawlowski +5
Although substantial progress has been made in reconciling LCDM simulations with the observed abundance and distribution of satellite galaxies, important tensions persist. Studying…
Stellar tidal streams around nearby spiral galaxies with deep imaging from amateur telescopes
David Martinez-Delgado, Michael Stein, Joanna D. Sakowska +26
Tidal interactions between massive galaxies and their satellites are fundamental processes in a Universe with L-Cold Dark Matter cosmology, redistributing material into faint featu…
Three Quenched, Faint Dwarf Galaxies in the Direction of NGC 300: New Probes of Reionization and Internal Feedback
D. J. Sand, B. Mutlu-Pakdil, M. G. Jones +18
We report the discovery of three faint and ultra-faint dwarf galaxies -- Sculptor A, Sculptor B and Sculptor C -- in the direction of NGC 300 (D=2.0 Mpc), a Large Magellanic Cloud-…
Extragalactic Stellar Tidal Streams: Observations meet Simulation
Juan Miro-Carretero, Maria A. Gomez-Flechoso, David Martinez-Delgado +11
According to the well established hierarchical framework for galaxy evolution, galaxies grow through mergers with other galaxies and the LambdaCDM cosmological model predicts that…