A recent rendition provided by the European Space Agency’s (ESA) Euclid observatory showcases two substantial celestial bodies: NGC 646 and NGC 646b. While these entities present as proximate companions, their actual separation spans an impressive 45 million light-years.
This Euclid image depicts the barred spiral galaxy NGC 646 alongside NGC 646b, a more diminutive, faintly discernible, and rounded galaxy. Attribution: ESA / Euclid /Euclid Consortium / NASA / M. Schirmer, MPIA / CC BY-SA 3.0 IGO.
NGC 646 resides approximately 392 million light-years distant, situated within the celestial expanse of Hydrus.
This particular barred spiral galaxy was initially documented on November 2, 1834, by the eminent British astronomer John Herschel.
Also recognized under the designations ESO 80-2, IRAS 01357-6508, or LEDA 6010, it is receding from our vantage point at a velocity of roughly 8,145 kilometers per second.
“Within this captured view from Euclid, NGC 646 appears in proximity to a smaller galaxy situated to its left, designated PGC 6014 (NGC 646b),” communicated members of the Euclid Consortium in a formal declaration.
“Although they give the impression of being neighbours, they are in fact separated by approximately 45 million light-years, with PGC 6014 positioned at a distance of 347 million light-years from Earth.”
“Consequently, any gravitational interplay between them, should it occur, would be exceedingly tenuous and ephemeral.”
By the conclusion of 2026, the ESA and the Euclid Consortium are slated to unveil the inaugural year’s worth of observational data, encompassing an expanse of roughly 1,900 square degrees of the celestial sphere (constituting approximately 14% of the overall survey territory).
These forthcoming images are anticipated to reveal hundreds of thousands of galaxies in exceptional clarity.
Furthermore, they are expected to furnish novel perspectives on the mechanisms of galactic formation and evolution, and elucidate the increasing prevalence of barred galaxies as the cosmos matures.
“Relative to the billions of galaxies that Euclid is scheduled to observe throughout its six-year tenure, NGC 646 is in fact quite near,” remarked the astronomers involved.
