phys.org | 2024 feb 02
TY4YA Jac"A team of astronomers, led by Arizona State University Assistant Research Scientist Tim Carleton, has discovered a dwarf galaxy that appeared in James Webb Space Telescope imaging that wasn't the primary observation target. Galaxies are bound together by gravity and made up of stars and planets, with vast clouds of dust and gas as well as dark matter. Dwarf galaxies are the most abundant galaxies in the universe, and are by definition small with low luminosity. They have fewer than 100 million stars, while the Milky Way, for example, has nearly 200 billion stars.
- A color-composite image of PEARLSDG made with JWST NIRCAM data. Individual stars are visible as small points of light in the image. Its somewhat dull color and lack of many bright stars is consistent with its old age and lack of ongoing star formation. Credit: NASA, ESA, CSA, Jake Summers (ASU), Jordan C. J. D'Silva (UWA), Anton M. Koekemoer (STScI), Aaron Robotham (UWA) and Rogier Windhorst (ASU)
Recent dwarf galaxy observations of the abundance of "ultra-diffuse galaxies" beyond the reach of previous large spectroscopic surveys suggest that our understanding of the dwarf galaxy population may be incomplete."
...read more