NGC 4151 is an intermediate spiral Seyfert galaxy with weak inner ring structure located  from Earth in the constellation Canes Venatici. The galaxy was first mentioned by William Herschel on March 17, 1787; it was one of the six Seyfert galaxies described in the paper  which defined the term.
NGC 4151 is an intermediate-sized spiral galaxy with a faint inner ring structure located about from Earth in the Canes Venatici constellation. This galaxy was first mentioned by William Herschel on March 17, 1787; it was one of six Seyfert galaxies described in the paper that coined the term.