Largest DSO's ?

How many DSO's have a visual size larger than 30' ?

What are the most popular ones?

Thanks.........Mike

Here's the reply that I made to your post on another forum.

Of the 1866 NGC objects discussed in Burnham's Celestial Handbook:

36 open clusters are 20 to 40 arc minutes, 7 are 40 arc minutes to 1 degree, and 3 are 1 to 2 degrees in diameter

3 globular clusters are greater than 20 arc minutes in diameter

18 planetary nebulae are from 1 arc minute to 1 degree in diameter

9 bright diffuse nebulae are from 20 to 40 arc minutes, 5 from 40 arc minutes to 1 degree, 10 from 1 to 2 degrees, and 10 greater than 2 degrees in diameter

11 galaxies are greater than 20 arc minutes in diameter.

Dave Mitsky

IC 1396 is very nice under dark skies, and very large.

Clear skies, Alan