This NASA Hubble Space Telescope image features the dwarf irregular galaxy ESO 490-017, roughly 12,000 light-years in diameter and some 23 million light-years away in the constellation Canis Major. The galaxy’s low surface brightness makes it appear as a faint, starry swarm behind brighter foreground stars that are easily recognized by their diffraction spikes. Numerous red, orange, and beige dots are distant galaxies peppering the black background, many exhibiting distinct spiral structure.
The data in this image of ESO 490-017 was part of a Hubble observing program that looked at the movement of galaxies and galaxy clusters through space. Matter in the universe is distributed unevenly, and the gravitational influence of that matter drives the “cosmic flow” or movement of large-scale structures in the universe.
Hubble is uniquely capable of providing distances to nearby galaxies like ESO 490-017 by measuring the luminosities of low-mass red giant stars as “standard candles”. The observing program also provided a legacy archive of the types of stars in local galaxies.
Media Contact:
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NASA’s Goddard Space Flight Center, Greenbelt, MD
claire.andreoli@nasa.gov
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