<Li> Messier 77 (NGC 1068), one of the first Seyfert galaxies classified </Li> <Li> Messier 81 (NGC 3031), the second brightest Seyfert galaxy in the sky after Centaurus A </Li> <Li> Messier 88 (NGC 4501), a member of the large Virgo Cluster and one of the brightest Seyfert galaxies in the sky . </Li> <Li> Messier 106 (NGC 4258), one of the best known Seyfert galaxies, has a water vapor megamaser in its nucleus seen by 22 - GHz line of ortho - H O . </Li>

What is the difference between type 1 and type 2 seyfert galaxies