NGC 6027a

NGC 6027a is a spiral galaxy and a member of Seyfert's Sextet, a compact group of galaxies located in the constellation Serpens. While appearing to be part of a gravitationally bound group, it is considered an optical illusion. NGC 6027a is much further away than the other members of the Sextet, lying at a distance of approximately 860 million light-years from Earth. The other galaxies, NGC 6027, NGC 6027b, NGC 6027c, and NGC 6027e (along with a tidal tail designated NGC 6027d), are at a distance of roughly 190 million light-years, making them a true interacting group.

NGC 6027a appears in the same line of sight as the Seyfert's Sextet galaxies, but is not physically interacting with them. Its spiral structure is clearly visible in astronomical images. Its apparent proximity to the other galaxies in Seyfert's Sextet is merely a result of its position along our line of sight. Its redshift confirms the significantly greater distance. Because of its misleading appearance within the group, NGC 6027a serves as a compelling example of how line-of-sight effects can influence astronomical observations and interpretations.