question: NGC 1808 is a Seyfert galaxy located in the constellation Columba, The which astronomical event that occurs during the last stellar evolutionary stages of a massive star's life, whose dramatic and catastrophic destruction is marked by one final titanic explosion, 1993af appeared in NGC 1808?
answer: Supernova
context: Title: NGC 185
  Passage: NGC 185 (also known as Caldwell 18) is a dwarf spheroidal galaxy located 2.08 million light-years from Earth, appearing in the constellation Cassiopeia.  It is a member of the Local Group, and is a satellite of the Andromeda Galaxy (M31).  NGC 185 was discovered by William Herschel on November 30, 1787, and he cataloged it "H II.707".  John Herschel observed the object again in 1833 when he cataloged it as "h 35", and then in 1864 when he cataloged it as "GC 90" within his "General Catalogue of Nebulae and Clusters".  NGC 185 was first photographed between 1898 and 1900 by James Edward Keeler with the Crossley Reflector of Lick Observatory.  Unlike most dwarf elliptical galaxies, NGC 185 contains young stellar clusters, and star formation proceeded at a low rate until the recent past.  NGC 185 has an active galactic nucleus (AGN) and is usually classified as a type 2 Seyfert galaxy, though its status as a Seyfert is questioned.  It is possibly the closest Seyfert galaxy to Earth, and is the only known Seyfert in the Local Group.
  Title: NGC 375
  Passage: NGC 375 is an elliptical galaxy located in the constellation Pisces.  It was discovered on September 12, 1784 by William Herschel.  It was described by Dreyer as "pretty faint, small, round, brighter middle."  Along with galaxies NGC 379, NGC 380, NGC 382, NGC 383, NGC 384, NGC 385, NGC 386, NGC 387 and NGC 388, NGC 375 forms a galaxy cluster called Arp 331.
  Title: NGC 4477
  Passage: NGC 4477 is a barred lenticular galaxy located about 54 million light-years away in the constellation of Coma Berenices.  NGC 4477 is classified as a type 2 seyfert galaxy.  The galaxy was discovered by astronomer William Herschel on April 8, 1784.  NGC 4477 is a member of Markarian's Chain which forms part of the larger Virgo Cluster.
  Title: NGC 380
  Passage: NGC 380 is an elliptical galaxy located in the constellation Pisces.  It was discovered on September 12, 1784 by William Herschel.  It was described by Dreyer as "pretty faint, small, round, suddenly brighter middle."  Along with galaxies NGC 375, NGC 379, NGC 382, NGC 383, NGC 384, NGC 385, NGC 386, NGC 387 and NGC 388, NGC 380 forms a galaxy cluster called Arp 331.
  Title: Supernova
  Passage: A supernova plural: supernovae or supernovas, abbreviations: SN and SNe) is an astronomical event that occurs during the last stellar evolutionary stages of a massive star's life, whose dramatic and catastrophic destruction is marked by one final titanic explosion.  This causes the sudden appearance of a "new" bright star, before slowly fading from sight over several weeks or months.
  Title: NGC 7479
  Passage: NGC 7479 (also known as Caldwell 44) is a barred spiral galaxy about 105 million light-years away in the constellation Pegasus.  It was discovered by William Herschel in 1784.  Supernovae SN 1990U and SN2009jf occurred in NGC 7479.  NGC 7479 is also recognized as a Seyfert galaxy and a Liner undergoing starburst activity not only on the nucleus and the outer arms, but also across the bar of the galaxy, where most of the stars were formed in the last 100 million years.  Polarization studies of this galaxy indicate that it recently underwent a minor merger and that it is unique in the radio continuum, with arms opening in a direction opposite to the optical arms.  This feature, along with the asymmetrical arms of the galaxy and the intense star formation activity are attributed to a merger with a smaller galaxy.  This galaxy is similar in both size and morphology to the barred spiral NGC 1300.
  Title: NGC 2782
  Passage: NGC 2782 is a peculiar spiral galaxy that formed after a galaxy merger in the constellation Lynx.  The galaxy lies 75 million light years away from Earth, which means, given its apparent dimensions, that NGC 2782 is approximately 100,000 light years across.  NGC 2782 has an active galactic nucleus and it is a starburst and a type 1 Seyfert galaxy.  NGC 2782 is mentioned in the Atlas of Peculiar Galaxies in the category galaxies with adjacent loops.
  Title: NGC 1808
  Passage: NGC 1808 is a Seyfert galaxy located in the constellation Columba.  The Supernova 1993af appeared in NGC 1808.
  Title: NGC 3077
  Passage: NGC 3077 is a small galaxy, a member of the M81 Group, which is located in the northern constellation Ursa Major.  Despite looking much like an elliptical galaxy, it is peculiar for two reasons.  First, it shows wispy edges and scattered dust clouds that are probably a result of gravitational interaction with its larger neighbors, similar to the galaxy M82.  Second, this galaxy has an active nucleus.  This caused Carl Seyfert in 1943 to include it in his list of galaxies, which are now called Seyfert Galaxies.  However, NGC 3077, though an emission line galaxy, is today no longer classified as a Seyfert galaxy.
  Title: NGC 2768
  Passage: NGC 2768 is a lenticular galaxy located in the constellation of Ursa Major.  It is at a distance of 65 million light years from Earth.  NGC 2768 is an example of a Seyfert galaxy, an object with a supermassive black hole at its centre.  A dusty structure is encircling the centre of the galaxy, forming a knotted ring around the galaxy’s brightly glowing middle.  This ring lies perpendicular to the plane of NGC 2768 itself, stretching up and out of the galaxy.  The dust in NGC 2768 forms an intricate network of knots and filaments.
citations: NGC 1808 Supernova